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MG MGB Technical - MGB won't start after 20 year layup

Hi Guys

I've recently bought an MGB that has been locked away in a garage for 20 years

Although the Garage has no roof on and the Car looks in a pretty bad way all covered in Pigeon Droppings and assorted other crud

Though She is all Original with virtually Zero rust but I've had to replace all the Fuel Pipes, which had just crumbled away and also replaced the points in the fuel pump

Then having cleaned the Spark Plugs, which also looked quite bad, I put them back in the Car and tried to Start Her

At one point I almost had her running, with continued assistance from the Self Started

But then She went pfut and just wouldn't fire after that

So then I pulled one of the Spark Plugs to have a look at the Spark, which was a very weak orange

So first job Tomorrow is to get some new Spark Plugs as they certainly looked a bit warn

Any ideas what type I should get and any ideas how I can get her started?
J Tayler

First thing I'd check is that points gap is correct and that points are clean. Also use new fuel and ensure float chambers are clean.
Peter Allen

For spark plugs, many people - including myself - use NGK BP6ES.
Dave O'Neill 2

Hi Peter

Its such a long time that I've had a Car with a Rotor Arm and Points, that I didn't give that a thought

Cheers Dave She's already got NGK BP6ES so I'll get some more of those
J Tayler

Hi, welcome,
to help you remember more things are and help you on your car, if you haven't already got one, I'd strongly recommend you buy the relevant (reprint) copy of the (factory) Driver's Handbook (this is not the same as a Haynes or, better still, factory Workshop Manual).

You can also use it now to get you started with factory settings that you can adjust from to allow for any changes over the last 40-50 years.

It also covers the driving and controls of the car, the servicing and maintenance and how to do that work and the settings.

(ther suppliers are available) -
https://mgownersclubstore.co.uk/catalog/Online_Catalogue_Handbooks_5.html

An example of the contents for my midget below.

You could also if you wanted to complete a 'vehicle profile' and may it viewable so it's possible to see which model and year of B you are referring to (there are lots of variations to what looks like the same car over the years and models).

You've already found how useful Paul Hunt's info can be, he also has an excellent site crammed with info on Bs (hammer & spanners) - http://www.mgb-stuff.org.uk/hometext.htm

Good luck J Tayler.



Nigel Atkins

Make sure you have oil in the dashpots!

set the choke

Hmmm What year is your car?

S

Hi Nigel @ S.D Devine

Cheers Guys, very sound advice but as I said its been years since I've had a Car with points

So going retro will take some getting used to so today I am going to clean the points and the Rotor Arm

To see if I can get a better Spark than the very weak orange one I am getting at the moment

I am also thinking that the Carbs might be gummed up, so I'll give them a squirt of Carb cleaner

The Car is a 'T' reg Rubber Bumper in Brown Gold sadly neglected and looks a hell of a mess at the moment

And She's still stuck in this tiny little garage which is so small that you have to walk sideways to get round

Which makes doing anything on the engine a real nightmare although I almost had her running once with assistance from the self starter

Where She was firing on every spin but nothing now the engine just won't fire

Thanks again for your help and suggestions

J Tayler

With a non-runner new to you it could be absolutely anything.

You mentioned earlier the pump was now working, when that first happened it should have chattered away like billy-oh for a couple of seconds while it filled the float chambers, did it do that?

After cranking a bit with the choke out the plugs should smell strongly of fuel, if not be wet. If they are dry no fuel is getting through.

If you have HS carbs with the float chambers on the sides it's easy to check the fuel level in the float chambers, also easy to check the choke mechanism is pulling the jets down.

You seem to have a spark, but are the plug leads fitted in the tight order? Should be 1 3 4 2 counting ANTI clockwise.

Check that the leads are going to the right plugs. With the plugs out and your thumb over No.1 plug hole turn the engine manually until you can feel compression lifting your thumb off, then keep winding until the No.1 piston gets to the top as observed through the plug hole. See which cap contact the rotor is pointing at, and that lead goes to No.1 plug. Count the rest from there.

Whilst in that area check the static timing is about 10 degrees BTDC.

paulh4

A complete MGB workshop manual is available to download from this website
http://www.geomatique-liege.be/MGJP/DocumentsPDF/MGB_Workshop_Manual.pdf
Andy Robinson

Hi Paul

She's got Twin SU Carbs and the Plugs leads are on the right plugs

When I managed to fix the Pump as per your instructions I got Fuel Straight away

and I even pulled the Fuel Pipe off the Carbs to check with the Ignition on (don't try that at home!) and Fuel shot out like a Fire hose

So it seems that fuel is getting to the Carbs and just wondering if I should try starting her with the Air Cleaners off?

I did take the Air Cleaners off once and I was able to lift the Carb pistons up and down with no signs of sticking

When I almost had her running on every revolution of the Starter there was a very distinctive 'Pfut' noise and then She refused to fire after that

The Plugs did seem a bit dry but the Spark from the Spark Plugs looks also very weak and orange instead of big and blue

But as you say it could be anything, so I will take the distro Cap off and see if the points and rotor arm are dirty and then clean them

Such a shame as this Car has mega potential only done 98,000 miles only 4 owners

No rust and unrestored although you wouldn't think that after 20 years of neglect
J Tayler

Not macho I know but do some reading of the Workshop Manual and get that Driver's Handbook, reading is research, same as researching here and on Paul's site.

If spark is weak, you're gonna struggle.

Again not macho but you always have to cover the basics to be able to successfully move on.

You've looked at fuel but the first thing I used to do with any car new me especially very old cars called classics is charge (or change) the battery(ies). It's really important to have the battery(ies) fully charged and in good condition with all the connections in good condition, clean, secure and protected. This goes for the earths, battery(ies), engine to chassis.

A good battery(ies) in good condition and state of charge, with all connections in good condition, means you have more power to fault-find on starting and the running the engine and on other electrical items – a drained or draining battery(ies) can hinder or stop the fault-finding process.

The 'Pfut' to me (a total non-mechanic and non-technical) suggests a misfire perhaps over fueling but it could just be build up from using choke and not starting.

Yes take the air filters, check them, clean them and/or replace the filters.

The plugs are there, are they gapped correctly, then work back check and clean the HT leads and their connections. The dissy cap, inside and out, the posts inside, the rotor arm - be careful with the CB points (see below) clean and lubricate carefully, set gap.

Again not macho but most maintenance and servicing and many repairs basically boil down to cleaning and lubricating, clean and where required lubricated parts and components tend to work better increasing performance.

T reg is '78-'79 registered but that doesn't always mean that was when it was manufactured the GAN number will give an approximate build date which can give you a lot of information on what would have been on the car from new - but of course much could have changed over 40 years. Don’t assume the part or component fitted to your car is/was the original or correct type or that it is fitted or working fully correctly, check and cross reference the information you have (and do the same when ordering parts or components, check and cross reference the information).

The Driver's Handbook would tell you where to find the GAN plate (and WSM).

See drawing below from my Driver's Handbook (notice there's a theme here) for the correct order to put the CB point wires back in.

The very first thing you should do is remove the battery(ies) and make sure they are fully charged and retain that full charge - as the number of times I've sen and heard of a car not starting because the batteries were not fully charged or fully holding the charge, or the connections were poor, loose or not fully clean or poor earths.

One of the main causes of general car breakdown is batteries but rarely is it a battery fault it's actually caused by the car's owner/driver use and care of the battery.






Nigel Atkins

A failed condenser will result in a significantly weakened spark.

You can check that one of two ways - the first is to flick the points open by hand with the coil lead connected to a plug and compare that tapping one of the coil wires on and off its spade. If they both give the same spark the condenser has failed.

The second way is to connect a second condenser temporarily between the white/black wires on the coil and earth and look at the spark then.

You can remove the air cleaners and check that each piston can be raised against damper resistance, then drop smartly back down with a click when released, although problems with the damper won't affect initial starting.

Didn't notice the reference to year before, it should have HIF carbs without the float chambers on the side, so difficult to check both fuel level and enrichment, other than the cam and shaft turning as the control is pulled. However if you connect a tube to the overflow of each carb in turn, and blow in it while holding the piston up, you should see fuel bubbling up from the jet.

'GAN' numbers refer to Midgets, I believe. MGBs have G-HN prefixes for roadsters and G-HD for GTs. T reg would be 78/79, and the full chassis or car number would be G-HN5 or G-HD5 with a number in the region of 470000 to 500000, with a G suffix. It could be earlier if it languished unregistered for some time.

paulh4

Yes, apologies, GAN for Midgets, obviously my mind's default setting.

Also - I was thinking check the gapping of new spark plugs just in case.

J Tayler,
a second golden rule you may not be aware of -
new parts or components can be faulty so don’t assume because it’s new it must work – if possible check that all new parts and components work fully and will fit your car well in advance of starting the work so that you can exchange them in plenty of time.

Unfortunately there are a lot of modern made new parts that are piss-poor to useless, these can include parts like condensers, CB points, rotor arms and dissy caps and newly made can go back many years so be aware of this. The car may not have moved out of the garage but new parts may have been fitted over those 20 years just to start the engine and have it running (not a great idea as it does nothing to keep the rest of the important systems in good condition, and the engine is one of the least important parts of any vehicle) and poor quality parts go back 20 years in my experience of 25+ years of running various classics as dailies.
Nigel Atkins

Nigel@Paul

Excellent advice, especially about having the Battery Fully Charged

Somebody must have read someone else's mind as I put the Battery on Charge last night!

Now for the really good news along with some bad news

Not knowing any better, I decided to go for the Nuclear Option and tipped a teaspoonful of Petrol down each of the Plug holes to try and see if it was a Fuel Problem

Put the Plugs back turned the Key and She fired just the once

So then I took the Plugs out and found they were all wet and so I dried the Plugs off and did exactly the same thing again!

But this time She really did try and start in a stumbling sort of way, where in order to try and keep her going I had to keep pumping the accelerator to stop the engine from dying (no choke being used)

Right from the Start I also had 80psi Oil Pressure as well, then after about 5 minutes I was able to reduce the RPM from 4000 down to 1000

To the point that She was ticking over without any Choke and sounding absolutely Ace with the kind of exhaust note that you don't get on a Mazda!

Then disaster struck! as from sitting behind the Wheel half in and half out of the Car, I could see a load of Steam and Water coming out

Where on closer inspection Steam and water were Jetting out where the Top Hose goes onto what I am guessing is the Thermostat Housing

Spraying out of that Top Hose where the Hose Clip goes like a Steam Cleaner much worse than what it looks like in the Photo

At which point I switched her off before something even worse happened and asking you guys for help

Not sure where to go from here and hoping its not the water pump

But the good news is She's running and sounds lovely and can't wait to get her out of the PO's garage and put her onto a trailer to get her home

As the garage that She is in is the size of a Shoe Box and the Car is surrounded by junk

Also how do I get email notifications if someone replies?

If you would be kind enough to help me get this Water problem sorted then I'll be a very happy Bunny

Thanks For Your Help

See Photo Water Spraying out of that Top Hose where the Hose Clip is all over the engine and not sure what to do next





J Tayler

Doesn't sound as if you're a million miles away. After 20 years those carbs had stale fuel in them which has probably left a deposit. Sooner or later you'll have to clean them.

On hose front, it could be top hose has perished. That's the easy bit. Fan belt intact? Not slipping? Check water pump pulley turns smoothly. Same for alternator. It could be as bad as rad blocked - sometimes central heating cleaner (Fernox or similar) can do wonders here.
Peter Allen

Hi Peter

Top Rad Hose is OK havent checked the water pump or alt fanbelt yet but do you think it could be a Stuck Thermostat?
J Tayler

J,
really, you ran an engine you don't know at 4,00rpm for 5 minutes!!

This ain't an MX-5 and it's a 40 year old car left in a garage for 20 years you need to be a bit more careful and gentle until you've got the whole car (not just the, relatively unimportant, engine) fully serviced, maintained, repaired and regularly run.

Do you know if the car can be dragged or pushed out, are the wheels/brakes seized on, steering lock off, tyres inflated.

Have you got that book on order yet.

You only get notification of the first reply to your thread and can only post one (not too large) photo per post, think of this board as being a classic.

If you want my basic (non-technical, non-sexy) notes for new owners (you'll have to convert them to MGB from Midget though as I've lost that set) then just email me. As others you'll mostly totally ignore them and then after a year's ownership of the car understand the worth of their basic simplicity.

(very simple) my first and last name at bt internet dot com

Good news your photo already looks better than the last new Midget owner we're trying to help out.

It's easier and cheaper to learn by the information and experience (including mistakes and opinion) you can get from the the people here than going it alone.

Good luck.
Nigel Atkins

Difficult to tell on the photo but the stat housing end jubilee clip looks funny is it on correctly (at all?)?
Nigel Atkins

Hi Nigel

I think I'll have to drive her out of the Garage as that's the only way I'll know if the Brakes are Stuck once I get this Water leak sorted out
J Tayler

"Spraying out of that Top Hose where the Hose Clip goes"

Hoses are bound to be suspect after 20 years, things seem to last much longer when they are being used. It's the fuel hoses you want to be looking closest at, especially on that era as originally - going by what was on a similar barn find - they are very thin-walled.

From your description it's the hose that has failed by the clip, but you say the top hose is OK. What makes you say that?

To me the Jubilee clip looks like it just has a lot of extra strap sticking out past the threaded bit.

Running it up from cold you should have been checking the radiator and the top and bottom hoses for increasing temperature, as well as round the thermostat housing. The latter should warm steadily, the hoses and rad should get suddenly hot after a few minutes running as the thermostat opens.

If the thermostat was stuck closed, or there was some other problem in the cooling circuit such that the radiator didn't get hot, the water and steam would start coming out of the radiator overflow as the pressure increased beyond that of the radiator cap.

Try it again, but more gently! Also use the choke, they almost always need some. Pull it out all the way, then as soon as it catches push it back half-way and see how it runs. But if it doesn't fire within a few seconds of full choke it's probably not going to and leaving it out will flood it.
paulh4

Hi Nigel

I did make a start on this today by getting a Haynes Manual, which unfortunately did not seem to help me with this problem

What makes matters worse is this MGB has been really tightly squeezed into this narrow garage, which makes it almost impossible to get from behind the wheel to check on the engine and then get back in the car

Basically what happened is after I managed to start her I had to keep pumping the Throttle to stop the engine from dying

So it wasn't constantly 4000rpm and whenever it was possible I kept the RPM down as much as I could

But when the Water in the System started to get hot, the only way that the Steam could escape was by trying to blow the Top Hose off the Thermostat Housing

Which could have been down to quite a number of things

(1) Stuck Water Pump

(2) Stuck Alternator stopping the Water pump from turning

(3) Thermostat Stuck Closed

(4) Blown Head Gasket

So after taking off the Belt

(1) Water Pump Not Sticking

(2) Alternator Not Sticking

Which unless you can think of anything else seems to leave only Two things that it could be

(1) Possible Blown Head Gasket (I hope Not)

(2) Stuck Thermostat Not Opening

Do you think a Stuck Thermostat could cause the System to pressurise to the extent where it would try to blow the Top Hose off the Thermostat Housing?

Do you think that could be possible as it seems to be the only thing that might do that apart from a blown Head Gasket

Slight extra problem being that the Thermostat housing bolts do not want to undo

So I'm thinking of using a Rattle Gun Impact Wrench also soaking those bolts overnight in penetrating Oil

Thanks for your Help

John
J Tayler

Just be very gentle with the thermostat housing bolts. They break for fun!!

Dont use a rattle gun! Gentle pressure is required. Are they bolts or nuts on studs? Unfortunataly they tend to grow into the thermo housing. Be prepared for the worst.

Colin
Colin Parkinson

John,
Haynes can be ok (mainly for keeping your tea mug insulated from the cold or leveling off a table leg) but it's not my favourite book by a long way, although I have two copies, 9 years apart, for the Midget both with similar errors and omissions.

Before you get the rattle gun see if you have any good quality releasing/penetrating fluid like PlusGas - and not ordinary WD40 - and a couple of bucket loads of patience, tends to be in short supply nowadays but often worth its weight.

Apply the likes of PlusGas to fitting generously, leave to soak in as long as possible, at least overnight, longer if possible, try to tighten the fixing to break the muck/crud/rust seal before trying to loosen if it doesn't work then soak in the likes of PlusGas and repeat.

You don't want to break the studs trying to get the nuts off, with or without the use of the likes of PlusGas.

A rattle gun is used generally same way as when you'd use a hammer and chisel instead of a spanner or screwdriver.

Where ever you can always use hand-tools instead of power tools, unless you're old and feeble like some of us. FBHs have there place but not for this sort of thing, better used on computers and mobile devices.

Do you have AF/imperial spanners of the correct size for the nuts & bolts on the cars the correct size tool will ease installation and removal.

What makes you think it's head gasket failure (HGF)?

If the stat is stuck closed then there only possibly a small hole for the steam to get through you'd have to build up a fair amount of steam for it to blow through the top hose I'd have though but who knows - what the story of the jubilee clip. See Paul's post - your top hose would need to be blocked solid too - perhaps it is, you could take it off at both ends and check, do not hold it up to your eyes to look through it as your eyes are very precious and if sh*t gets in them it can be bad especially if you're by yourself somewhere remote or out of earshot.

The cooling system could be blocked (solid?) somewhere, anywhere, have an airlock or no coolant in section(s). Have you checked the rad for coolant.

You could take a gallon or two of water with you and some stiff wire and check to see if coolant flows freely out of the engine block at the drain and out of the rad and use the wire to check for blockages at any access points like hoses.

Refill by the instructions in the DH to avoid hotspots and airlocks - or see wot 'aynes sez.

Would it not be easier to drag the car out and trailer it to a more convenient location and then commence the required work or look at it in the full light of day.

I'm a bit worried about a car stored for 20 years, the garage has no roof yet there no (visible) rust. The engine might start and that's good but the engine is one of the least important parts of the car. Obviously I don't know, the car might be an absolute cracker.

Nigel Atkins

Hi Nigel@Colin

Sometime before I started her up, I checked the Rad for Coolant and it was Full and looked quite clean

Where in order to check this, I took the Top Hose off and then when I put it back again also replaced the Jubilee Clips with a couple of New ones

So I think there must be a Blockage in the System somewhere

If only I could get to it I would pull the Top and the Bottom hose off to see if there was a blockage except this garage is so small that it is a bit of a nightmare to try and get round the Car

And also a bit of miracle that I managed to get her started and the fact she hasn't gone rusty is as much of a mystery to me as it maybe to you

As I can only put up one photo (apparently?) I will do a before and after just to give you a flavour of what She is like

This is what I found when I opened the Boot, so I was expecting the worst when I took out that Carpet



J Tayler

This is what I found when I took out that Carpet

Virtually nothing in the way of rust and even the photo makes it looks worse than it is


J Tayler

Pictures more pictures!
S

Hi SDD

I would love to put up more pictures but this system only allows me to put up one at a time but anyway here is another one and I will try and keep adding them in

Virtually no Space to get around the Car as you can see and I dare not try and Tow it out of the Garage in case it runs away and hits the Walls

As the entrance to this Garage is on a rather Steep Slope!


J Tayler

"the only way that the Steam could escape was by trying to blow the Top Hose off the Thermostat Housing"

On second thoughts that is possible with the later system with the remote expansion tank, but not for any of the reasons you describe. The only way that could happen is if the expansion path between the radiator and the expansion tank is blocked.

Other than that the cooling system is a closed circuit from engine, top hose, radiator, bottom hose and back to the engine. Pressure building up in the engine would be able to pass into the radiator by both the top hose and the bottom hose, both would have to be blocked to do what you describe.

You'd soon know if the water pump were stuck - the belt would probably squeal like a banshee.

Thermostat could well be stuck, feeling the radiator as the engine warms up will tell you that - it would never get hot.

There could be a blown head gasket, but that would push coolant out of the expansion tank overflow not blow the top hose off - as long as the expansion path from radiator the tank is clear.

"I checked the Rad for Coolant and it was Full"

You can't check that type of radiator for coolant level. You would have to remove the filler plug on the thermostat housing to check the engine, and remove the pressure cap on the expansion tank to check that was about half full when cold.

Did you remove the pressure cap on the expansion tank? If not it's possible that has welded itself to the neck so wouldn't release pressure, but unlikely.

By peering into the expansion tank while squeezing the top hose you should see the level go up and down slightly, and if the hose has been off probably bubbles. But if neither of those happens and the hose is hard and won't compress then the expansion hose or ports on radiator or expansion tank are probably blocked. The problem is that having taken the top hose off the coolant circuit will have some air in it which will compress quite easily even if the expansion path is blocked. So the only way to be sure that expansion path is clear is to remove the small hose between the two and blow through it, and the ports on the radiator and tank.

Check the pressure of the cap, should be 15lb. If someone has put a monster cap on it could blow the hose rather than the cap.
paulh4

Hi Paul

My Car has the later remote expansion Tank so you could well be right

But today I took off the Thermostat Housing which was made from some sort of Alloy Material that being dissimilar metals, had welded itself to the Studs

Whereby the only way that I could ever remove it, was to cut it in pieces with a hacksaw and even needed my Impact wrench to get the Nuts undone

That little job took over 2 hours but there was no other way

Anyway having eventually that off, I put the Thermostat in Boiling Water and found that it was stuck closed

So maybe that was the reason for the heated water trying to do its best to try and blow the Top Hose off

There was a Spare Thermostat Housing in this Garage that must have come from an earlier Car as the Water Inlet is facing the wrong way, though I think I can get around that at least for the moment with a longer piece of hose

And will probably leave the Thermostat out until I've got her home



J Tayler

That other housing is for the earlier arrangement without the expansion tank. In theory even if it fits it doesn't have the filler plug which would make filling difficult, although people with that arrangement have described removing the hose from the housing and turning it so the open end points upwards, and fill through that, as being easier than using the filler orifice anyway.

Whilst a thermostat stuck closed WILL cause the coolant to boil, it should vent from the overflow on the expansion tank, not blow the hose off. Lets hope it hasn't blown the head gasket or done overheating damage.
paulh4

Hi Paul

That is exactly what I did to check the Rad was full of Coolant

Though with the benefit of hindsight, as you say it should have vented out of the remote expansion Tank

When I eventually got the Thermostat out after two hours of carefully sawing off each corner of the housing

I dropped the Thermostat in Boiling Water and though it opened I'm not sure if it opened as much as it should have

So using this new housing which looks like it came from an earlier Car, I'll rig something up to Test it with convoluted tubing just to see if any water tries again to squirt out

I don't think I overheated her although you never know, as I didn't let her run for long

Another pic of the Car that was covered in rubbish




J Tayler

Hi Paul

Here is a Pic of the Remote Expansion Tank and the Pressure Cap looks a bit rusty, so maybe that was the problem




J Tayler

Hi Guys

I have now ordered the Correct Type of Thermostat Housing for my mgb roadster of the same type that I took off for Cars with the remote expansion tank together with some Uprated Gaskets

What type of Thermostat should I get 75o/c or 82o/c

UK Climate?

Also another Pic of my MGB


J Tayler

82C. 74C was for hot climates.
paulh4

Hi Paul

82C it is then + Another Pic of my B the Upholstery is ruined because the rain got in

In a Shed near this Garage are a Pair of Original Seats in A1 Condition from a 1968 MGB Roadster

Would they be a straight swap or are the fixing runners different in some way?


J Tayler

As far as I know they should be straight swap, the Parts Catalogue only shows one set of runners, but then they don't have the earlier seat frames. The wooden slats between the fixed runners and the carpet will probably need replacing under the circumstances.

The 68s don't have tilt and recline, I believe.

You may well have to keep any head restraints with the seats
paulh4

BTW, check the new stat has a bleed facility is shown in the attached. I've had one with neither and it makes filling the system impossible, and had to drill a small hole in the flange.


paulh4

Hi Paul

No idea if its got that hole or not but it was advertised as a Top Quality replacement £7 so if it hasn't got that hole I'll have to drill one

The Uprated Gaskets arrived Today and they look really good

And the housing and the Thermostat should be arriving next week

The possible good news being that I got a mate to check the Thermostat in Boiling Hot Water and he confirmed that the Thermostat wasn't opening at all!


J Tayler

Hi Guys

The Thermostat Housing turned up today but not the Thermostat!

Note to self in future order everything from the same supplier

The Thermostat Housing looks really good and is genuine OEM so while I am waiting for the Thermostat

What I am thinking of doing is putting the Thermostat Housing on and then running the Engine to not only see if I get the same overheating problem that I got last time

But also so Flush the Rad out with some of that OXY Plus which works great for cleaning out metal Tea Pots

Does anyone know what that hole in the Bracket is for on the leg that seems to be there for no reason, was it an alternative place for an Alternator or something like that?

Also a good job I saved that Black Plastic Plug £5 a piece!



J Tayler

Mounting point for the American air-pump, I think.

Is that stuff suitable for alloy, copper, iron and rubber?
paulh4

Hi Paul

No idea on that one but they use it as Stain Remover for Washing Clothes and I even used it to clean the inside of the Fuel Tank on my Jag and that came up like New!

Anyway the Story so far on the MGB

Put on the New Thermostat Housing with no Thermostat inside as it hadn't turned up but has now

Removed the Rear Brake Drums as the Hubs were seized Solid because the Brake Drums were binding

The Clutch isn't working but more of that in a minute

This Morning: Turned the key and She Started on the Button no signs of any Boiling up and She ticks over like a little Swiss Watch

75psi Continuous Oil Pressure

Water Temperature Normal even after half an hour of running

With the Brake Drums Still off, I got her into all the gears except reverse

I couldn't get any gears before as the Shafts in the Gearbox had gone dry and the Gear Lever wouldn't move out of Neutral

But running the Engine in gear seemed to work wonders

So I am going to put the Brake Drums back and then try her again

The Clutch master cylinder is empty, do I use DOT 3 or Dot 4 Brake Fluid or something else?

No doubt the Front Disc Brakes have seized but I'll try and tow her back a bit so I can bleed the Clutch

Who knows She may be drivable round the Garden after that

Thanks for your help
J Tayler

Good progress.

After a long layup the clutch friction plate can often stick to the flywheel or pressure plate so can't be disengaged at all, but I don't think that's the case here or you wouldn't be able to get any gears, not just reverse. More likely air in the hydraulics from fluid having drained out of the master causing the clutch to drag badly.

That's also quite likely the cause of 'not moving out of neutral' as if the clutch doesn't fully disengage the synchro rings in the forward gears won't let you select a gear, and it will grind horribly in reverse with no synchro.

Fluid is almost certainly DOT 4, or DOT 5.1 AKA Super DOT 4. Don't use DOT 5 as that is silicone-based and not compatible with anything else. Modern cars don't use silicone either as it's not compatible with ABS, so it's less available anyway. Fill the master, then pump the pedal slowly for a while. That probably won't do much, but if you leave it with the pedal wedged fully down overnight that will help to push air back to the reservoir. As air is expelled the clutch will get heavier as you will be moving the cover plate springs more.

You may have to try that two or three times, and if that doesn't work it will need proper bleeding, which can be a pain. As a last resort if you can get under the car use the release arm to push the push-rod all the way into the clutch slave as far as it will go, release it, and it should slowly move out again. Try that a couple of times as well. But look in the dust-cover on the end of the slave cylinder, if that has fluid in it it's going to need replacement anyway.

paulh4

Hi Paul

You are absolutely right, when I tried to get reverse there was a grinding noise like you described at which point I decided that I wouldn't repeat that exercise until I got the Clutch Working

But I have got lots of DOT4 and a syringe to fill up the Clutch Master Cylinder with and I also undid the Bleed Screw on the Clutch Master Cylinder

So I'll fill it up with Dot4 tonight and see how it feels in the Morning

Don't want to tempt providence but I really feel I'm getting there
J Tayler

Hi Paul

Clutch on the MGB is not fully returning or disengaging properly

Do you think I should buy a New Clutch Master Cylinder?

I'm probably going to end up replacing everything but just need to try and identify the main suspect

Should the Clutch Pedal have a manual return spring as it doesn't appear to have one from what I can see
J Tayler

Not sure what you mean by not fully returning. Do you mean that when you push the push-rod into the slave by hand it doesn't come back out? That could be corrosion in the bore hanging on to the seal, so should be replaced.

If the master secondary seal has failed fluid runs down the pedal and onto the carpet, so feel for that, although it could have happened 20 years ago of course and not be detectable now. If the pressure seal fails the clutch won't disengage, but you don't lose fluid.

At this stage I'd refill the master and hopefully get the clutch working, which at least should show you whether there is a problem with either master or slave. Slaves aren't worth messing about with changing seals, but for the master I'd remove the push-rod and piston and inspect the bore. If that is shiny throughout then new seals are worth a punt.

If you plump for new master and slave at this stage, and hose, you might as well pick the car up by its radiator cap, rotate everything below it one quarter-turn clockwise, remove, discard and replace. Then buy a new radiator cap :o)

The pedal should have a return spring, like the brake, but lack of one won't be having an adverse effect on basic clutch operation.
paulh4

Hi Paul

Managed to tow her out of the Garage today and tried to bleed the Slave Cylinder on the Clutch but Fluid was pouring out from somewhere before it got to the slave
also couldn't jack her up enough to have a proper look but there was a metal pipe with about 6inches of rubber pipe secured by hose clips please could you tell me what that pipe is for
J Tayler

There is a metal pipe down from the master cylinder to a bracket on the chassis rail, then a rubber pipe from there to the slave cylinder. Whilst the metal pipe is secured part way down, the rubber pipe just goes from the chassis bracket to the cylinder, no clips. Sounds like the hose has split badly, or may not even be connected.

The nuts on the bracket securing pipe and hose are pretty difficult to get to without removing the starter.
paulh4

Hi Paul

Cheers!

Now I've got the Car back home, I can now jack her up much higher to have a better look

As I now think that its either that Tube or else the seals have completely gone on the Master Cylinder

When I was trying to bleed the Slave on the Clutch with the help of a mate, Brake Fluid was literally pouring down from above

So I am suspecting the Seals have gone on the Clutch Master cylinder rather than that tube

In which case I'll have to take off that Shield around the Master Cylinders to find out for sure

Probably not worth repairing so I go and buy a New one, is there any particular make that you could either suggest or recommend
J Tayler

Just to reiterate, when the master seal has failed it runs down the pedal into the cabin. If the fluid is running down from the hose it's almost certainly the hose that has failed near the chassis bracket, or it's not connected. If the slave seals have failed or if the hose has failed by the slave it'll be dripping off the bottom of the slave itself.

For 'important' spares I always go to the main suppliers like Brown & Gammons, Moss or Leacy, sometime MGOC. Often there are two types available at significantly different prices, the cheaper ones usually with a suffix letter like 'X' on the end of the part number. Those are copies and best avoided.

paulh4

Paul,
have you got the 'x' bit right, I thought it was for alternative but not necessarily cheaper or (possibly even) poorer quality parts.

All the suppliers have some poor and piss-poor quality parts that they stock, often very cheaply made because that's what the tight-fisted classic owners insists on buying, doesn't matter to most of them as they rare use the vehicles.

If you can find them, sometimes very old NOS can be good.
Nigel Atkins

I've always taken the 'X' or equivalent as a legal requirement as the original part numbers are copyright and can only be used for parts made by the people with a licence to make the item to the original specification (not necessarily the original manufacturer note). Parts made by others copying the dimensions etc. cannot use that number, hence the suffix. So yes alternative, but I've only ever noticed those cheaper, and with my cynical hat on when cheaper they are not going to be better. As a case in point Moss offer clutch slave GSY106 at £46, and GSY106Z at £16.

There are still Lucas parts, as someone has bought the rights to use that name and the original part numbers. But they are made abroad by heaven only know who, and are nothing like the originals for quality, or even function going by their indicator flashers.

I agree NOS where you can get them are almost certainly going to be preferable to anything else. Judging by the parts that were on both my cars when I got them 30 and 24 years ago most of them would have been original, lasting longer in my ownership than subsequent replacements, many times longer if they are indeed original. The V8 clutch slave was quite possibly 25 years old with 170k on it, wheel cylinders 18 years and 100k in my ownership, quite possibly 38 years and 210k in total. I can't get over the fact that my roadster was only 16 years old when I bought it, and my V8 20. My ZS is 15 years old this year.
paulh4

Lucas is a good example, this Prince of Darkness stuff is rubbish as far as the original parts for 70s car at the very least. They gave decades of good service despite the cars getting so much user abuse and neglect.

Lucus NOS from say 20? years ago (when did they go from Solihull?) can be rubbish but older than that good.

I'm not sure if the part numbers are protected, unlike Audi patents(!), just taking a part dear to my heart from my good friends at Moss - GHK1142 claimed (it's not, not even a copy) original part, WHEEL BEARING KIT, front £13.50, whereas with the X added it's a totally different part and costs more and probably better quality as it will perform its function and for longer but is not original type - GHK1142X WHEEL BEARING KIT, front, tapered roller, £28.

Time passes very quickly Paul, talking to someone about their car and as I walked off I realised it was 20 years since I had that one.


Nigel Atkins

I'm pretty sure the Solihull alternator factory was still operating when we arrived here in 1975. Lucas Research were still here when taken over by TRW, since passed through a couple of owners. I think TRW may still on the building but passing it regularly I don't look any more.

Those wheel bearings are a different situation, being taper roller replacements for a ball-bearing original on Midgets, Minors and the like, and for that reason they have the suffix and a higher price. For the MGB the inner bearing for example GHB105 is £15, GHB105Z aftermarket £8.
paulh4

I think it was signed as Lucas when I used to pass it in the mid to late 90s but I might be wrong.

Just by the three examples given Z seems to stand for lower priced alternative (which can often mean much higher overall cost in the short or medium to long term) and X for outright alternative.

I couldn't see a code for these extra characters but I'd like to suggest adding - P for poor quality, P-P for piss-poor quality and J for yes we known it's an absolute joke but tight-fisted classic car owners demand it.

Nigel Atkins

Hi Guys

Today I took out the Clutch Master Cylinder which was still full of Brake Fluid and when I pushed in the piston, NO Brake Fluid came out of the pipe that goes into the Slave

I also took out all the Seats and the Carpets all of which were ruined and soaking wet but no rust on the Floorboards anywhere!

I'll also have a better look at that rubber tube tomorrow and see if its split or something

But strange the Clutch Master Cylinder isn't working and No Brake Fluid seems to be dripping inside the cabin

Very Strange



J Tayler

Very strange, if pushing the piston in with a full reservoir didn't push any fluid out, but earlier fluid was pouring out of somewhere.

But like cooling system thing was caused by at least two faults, there could be several with the clutch system.

If you end up changing both master and slave then definitely change the hose anyway.
paulh4

Hi Paul

Looks as if I may have a problem on two fronts with my non working Clutch

(1) The Clutch Master Cylinder isn't pushing out any Fluid when you push the piston in and although there was Fluid pouring out from underneath the Car when I depressed the Clutch Pedal there wasn't any Fluid leaking into the drivers Foot well which on closer inspection I agree there should have been

(2) Fluid was leaking out of somewhere before it got to the Slave and although the Rubber Tubing that goes from the Copper Tubing to the Slave looked sound enough, the Metal Screw Connections on each end of this connecting Tube look and feel very rusty

So what I am now thinking is that the Ferrules on each end of this Connecting Tube are now the Number One Suspect for the cause of Fluid Leakage from under the Car and in fact it looks so bad it needs replacing

So my Question is: What is the Best Way to take this Connecting rubber Tube off as I think it may have Male fittings on each end

Should I for instance unbolt the Slave and then unscrew it like that? or is there a different method that I should be using?

J Tayler

Male fittings both ends as you say.

You have to undo the nut on the pipe that is above the chassis bracket, then undo the nut on the hose fitting that is also above the chassis bracket.

Normally fittings like these both require open-ended or flare spanners, but it is sandwiched between the chassis rail and the starter, and at the very least the starter will almost certainly need to be removed. Alternatively a crows-foot spanner or socket can be used from above or below.

If one or other proves recalcitrant you could cut the hose away from the fitting, then grind the remainder of the fitting away from under the bracket. That will allow you lift the pipe with the upper part of the hose fitting away from the top of the bracket, to be dealt with on the bench. If the master is already out that should be relatively easy.

The hose is just unscrewed from the slave with the slave in-situ, but the other end of the hose has to be disconnected from the chassis bracket first one way or the other.

You can slacken the hose in the slave, then remove the slave from the bell-housing and unscrew it from the hose, but unless you were retaining the hose there is no point. If fitting a new slave unless the thread start is in the same position you will not be able to tighten the hose into the slave and refit the slave to the bell-housing without putting a twist in the hose, which should not be done.

For refitting you screw the hose into the slave (on the bell-housing) and tighten, remembering the copper washer, then push the other end of the hose up through the chassis bracket. Fit the fitting nut, then fit the pipe and its nut.
paulh4

Hi Paul

Cheers!

Sounds like a fun job, so I think I'll cut the hose and go from there

Thanks for your help
J Tayler

This thread was discussed between 22/04/2019 and 04/05/2019

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