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MG MGB Technical - Time for a service

Hi folks,
I've had my '73 BGT for about 3 weeks now. It's my first classic car. I don't know enough about cars to service it myself (although I have a multitude of manuals & magazines for the B, so I plan to learn the basics over the summer months).

I am leaving it in to have a full service tomorrow. The mechanic specialises in old cars & seems to be pretty familiar with the B. He recommends a full service every 6k miles (about 12 months driving for me) and a minor service every 3k miles. I would hope that this service should ensure (relatively) trouble free motoring until the minor service 6 months from now.

My question is this (and I know there are probably a million and one different answers) - what are the main areas I need to ensure he checks?

From driving the car over the past 3 weeks, the main things I have noticed are:

-She is slow to start on cold days
-The handbrake is very poor
-Lately the engine pressure has been dropping from 60 down to 20-30 even when warmed up. It even cut out this morning
-The gearbox makes a slight whining noise if I rest my hand on the gear shift when driving
- Acceleration is not smooth all through the range(i.e. sometimes it's like I'm a learner driver who hasn't mastered the gas/clutch pedal action - the car surges just after I have change gears)

Any tips greatly appreciated!
Mark Whelan

I am no expert but-
Slow starting on a cold day has more to do with thick oil, 20W50 (if that's what your using) and gas that doesn't vaporize easily in colder weather.
The handbrake needs an adjustment, Haynes should show that procedure.
When you say "engine pressure", do you mean oil pressure?
My gearbox makes the same noise if I rest my hand on it, I believe the experts will describe something to do with harmonic resonance.
The "surge" you describe is probably due to low end torque, mine feels better through the mid range. Probably something to do with the way your engine is set up, carbs, stock manifold, etc.
The experts are going to want more information such as which carbs are you using, is it the stock manifold and exhaust. The more info you give the more advice you'll get from the ones who know much more about it.
Lewis

I'm afraid I don't know much about the details of carbs, manifold etc. As far as I can gather, the car is pretty much standard. The only changes I'm aware of is the installation of 1 x 12V battery as opposed to the standard 2 x 6V. There is a new solid state fuel pump (whatever that is). Aside from that, the OD switch is non standard as are the seatbelts.

This will be sacreligious to the techs on the BBS - I haven't even opened the bonnet of the car since I bought it. I did have an MG guy check the car over before I bought & his notes were as follows:

There's a knock in the back diff (seems to be a common problem?)
Needs new front bushes, handbrake cable & rocker cover gasket
50lbs oil @ 1000 revs drops to 30lb at tickover
The petrol pump is noisy (clicks can be heard in the cabin)

Mark Whelan

Sounds like it just needs service by a compenent shop. His service recmendation is by the book. Bob Thompson
Bob Thompson

Mark, open the bonnet, half the fun of these older cars is their simplicity and ease of maintainance. Get your hands dirty, ah the love of grease!
I can't help you with the knock in the rear diff. I'm sure someone will.
My "B" also needs front bushes, I don't feel confident enough to start that project, also spring is finally here in New England and I don't want to lay it up for the summer. I don't know how difficult the handbrake cable is to replace.
The valve (or rocker) cover gasket is not a big job, I will be replacing mine next week, the gaskets are cheap through any of the part suppliers. While the cover is off check the valve clearance, re-adjust if needed. Again not difficult and a lot of information on that in the archives. (More than you 'll think you need).
The oil pressure is fine.
When you say the petrol pump is noisy, is it only at start up or can you hear the clicks all the time. The pump is supposed to click when you turn the ignition. When you turn the key you will hear the click until the pump has delivered the fuel to the carbs, you should not hear the clicking after start up, unless you are running out of fuel.
Mark, get a Haynes workshop book, and there is also one by Bentley (I think) that is supposed to be very good. Also check out this site
http://www.mgb-stuff.org.uk/
click on spanners, it is helpful. Good luck.
Lewis

Hi Mark

Yes all agreed, if you've had it 3 weeks and not had to open the bonnet it sounds like a good one :-)

I'd be careful with that oil pressure though. It could be low on oil. Lift the bonnet now and dip the oil - the stick is halfway along the sparkplug side of the block, clearly marked low-high and takes a pint between the marks.

As the others say, your new mechanic should sort the rest in the course of the service especially as it will be the first one for you both. If he's good he'll have a careful look round and report for you.

The handbrake is good when setup right but this is now an old car. It may have oil on the linings which is common from this type of axle, or leaking wheel cylinders. The good news is the parts are cheap, get the Moss, MGOC and loads of other parts cats, and the oil seals can be done without taking off the brake backplates so it's a cheap job. The rear bearings usually last forever so long as the axle has oil in it.

The key to it for you - until you get to doing it yourself - is to get someone who knows these cars as there is a lot that's not in the manuals and a lot that even good young mechanics will not be familiar with when they find no socket for the computer lead. I kid you not there's a whole generation now who've never worked on carbs, points and condensers. I found a lot wrong with my recent purchase which had expensive professional maintenance the last 4 years - some of it truly shocking - as in rear hub nuts finger tight instead of 150 lbs/ft.

Enjoy! Rich.
Rich

This thread was discussed on 22/03/2005

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