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MG Midget and Sprite Technical - killed my midget 1500

I have managed to kill my car.. . . . it was kinda overheating (I think because I didn't have the filler cap on the coolant expansion container on tight and the coolant blew up). . . . . That ain't the worst of it. . . what I did then was the most dumbass thing I can ever imagine doing. . .

I filled the coolant back up. . . . started it again and i think it had an air bubble which blew one of the hoses off trhe bottom of the radiator. . . put it back on etc

this is where it gets really dumb

Not only did i fill the water up through the filler bit near the temp sensor. . . .I also filled water in a filler bit that looked similar just behind this. . . . I quickly found out this was not where water went as it p1ssed through the carburettors. . . the engine is now ceased. . .

any thoughts? new engine?

thanks for any help

yours in grief Dave
d j kirk

Dave first things first we've all done stupid things in haste

I'm not too sure where you mean by >>I also filled water in a filler bit that looked similar just behind this<<

don't do anything until you get further advice

but FFS buy a copy of the owners Handbook as it tells you how to properly refill your cooling system along with loads of other stuff

http://www.mgocshop.co.uk/catalog/Online_Catalogue_Handbooks_5.html

you can refresh your memory on stuff like this before starting to do anything
N Atkins

The only other filler on the top of the engine would be the oil filler (2" ish metal cap on the top of the engine). Was it that?

-- Josh
J Levine

the reason for overheat and blowing off bottom hose may have another cause(?)

with more information (this second appeture, model year of car) I might be considering getting the comtaminated oil out of the engine and filter and cleaning/drying out the carbs

but I'm no expert

I'd also be thinking of fully cleaning and flush/back flush of whole water coolant system

but more info from Dave and expert advice from others is need here
N Atkins

Dave,
It sounds that you may have a more complex problem than just the initial one of forgetting to put the expansion tank cap back on.

First point: Without the cap, it should not have overheated enough to cause any real problem. It just meant that the system wasn't pressurised, so that it would start to boil at 100 C rather than the higher temperature (around 110 c I believe) that it can go to before boiling point is reached with a pressurised system i.e. with the 7lb cap on properly.

Second point: You say that you then filled it up but it "blew the bottom pipe off". An air bubble in the system wouldn't cause this. Either the pipe was faulty or something else more significant has occurred - possibly a blown head gasket which is over-pressurising the cooling system. I would do a compression test to check this.

Lastly, from your comment it sounds as if you put water in the oil filler cap, although I am not sure why this would then come out through the carbs? Anyway This shouldn't have caused any lasting damage, but will mean that you MUST get it all out. Remove the spark plugs and spin the engine on the starter. This will blow any remaining water out of the cylinders. Then drain the oil and remove the oil filter. Fit a new filter, refill with the correct quantity of the right oil (refer to your Owner's Handbook). Clean and dry out the carbs.

Let us know how you get on.
Guy
Guy

" the engine is now ceased"

or deceased, as the case may be.

Dave, I had a similar problem with an Allegro - kept overheating so I stopped every time the needle went into the red and topped up via the expansion tank. It turned out that the thermostat had stuck in the closed position. Eventually, while I was raising the bonnet to repeat the performance, the steam pressure in the engine blew the plastic filler plug straight out, stripping the threads. I was lucky that I was not scalded.

If your hose blew out under pressure it could have been the same cause. It was unlikely to have been the loose expansion tank cap as that would have relieved the pressure anyway.

If you filled the rocker cover with water via the oil filler cap, then that would have exited into the carbs via the rubber breather pipes

Dave
D MATTHEWS

Dave,

Another thought on this - if you poured water into the rocker cover via the oil filler cap, it shouldn't have entered the cylinders as the valve stem seals would have prevented that (although it would have found it's way into the sump)

However, if the water got into the inlet manifold by way of the rocker cover to carburettor breather pipes and you then tried to turn the engine over, water would have been drawn into the cylinders, which could have more serious results.

As Nigel and Guy have suggested - change the contaminated oil and filter and don't spin the engine over without the spark plugs being removed first.

Dave
D MATTHEWS

As correctly stated above a number of problems have occured.

The first thing you must do is establish where you have put water. A photo attached here could be worth a thousand words.

If water has been poured into the rocker cover then some careful draining and refilling is required. If it has entered the cylinders then not too much to worry about as the engine would simply suffer hydraulic lock and the starter motor would be incapable of turning the engine over.

If this has occured then removing the spark plugs and standing well clear whilst the engine is turned over will quickly eject any water in the cylinders.

I feel that it pay you huge dividends to find someone local to help you assess any damage and also help decide on what rectification is reqiired.
Robert (Bob) Midget Turbo

Bob,

Another factor here is whether the water was poured in while the engine was still running.

Dave
D MATTHEWS

Good point Dave, if that were the case then it would have stopped very quickly!!

Good assessment is definately required.
Robert (Bob) Midget Turbo

Agree with all the above. The most important thing now is to take things logically and not panic. The iron engines are as tough as old (metal) boots.

I don't do dumbass things to BRB... everything is carefully considered... like the time the engine wouldn't start and I'd just fitted a new plastic oil pressure pipe that passed close to the manifold (was going to tidy this later)... but the engine wouldn't start so no problem. Soon after the engine did start, there was a hazy smoke from near the manifold (but I'd just fitted a new one, and they smoke when first used, right? so no problem...) followed by a sudden burst of flame. Fire in the engine bay. Just stand there and watch it. Then switch engine off and put out the fire with an extinguisher. You see, no dumbass things here... all very logical and thought through.

A
Anthony Cutler

A favourite message from other interweb sites

"this thread is useless without picture(s")


Can you show us where you put the water on a photgraph please, this site makes posting pictures very easy

There are many very good advisors here all of whom are in the dark 'til we see where you put the water

:(
Bill 1

Well done Bill that what I meant to put, post a photo with more details

I've got the same suspicions as others but more details needed

a friend brought a car round no temp gauge on that model but a smell of overheating

the nice clean fresh coolant mixture in the clearish plastic expansion tank should have been a clue - the feeder pipe that came out the bottom was blocked solid so it looked good but wasn't

not the case here of course

with this and the elderly chap who drained the g/box oil instead of the engine oil you see why I recommend the owners Handbook

note for Dave when you get to refill oil, coolant, capacities are for totally empty so put at least a litre less in to start with allow to settle then check and top up as required
N Atkins

I suspect that Dave means he filled the inlet via the nut on top of the inlet manifold...

It could be confused as being part of the cooling circuit since the heater feed pipe runs adjacent to it through the manifold casting.

DH2
DH2

"I suspect that Dave means he filled the inlet via the nut on top of the inlet manifold..."

That's what I understood from the start. The take off on the inlet manifold is from the balance chamber and is for vehicles with a servo such as the Triumph 1500 TC/early Dolomite.

Unfortunately the balance chamber lies alongside the waterway for the manifold heating system.

I guess it's an easy mistake to make for the uninitiated.

It's all very well people saying turn the engine over with the spark plugs out but I would want the head off to check for damage. Furthermore, if Hydraulic Lock has occurred, then I'll bet a pound to a pinch of salt that one or more conrods is bent because these are not particularly strong in the 1500.




"Another thought on this - if you poured water into the rocker cover via the oil filler cap, it shouldn't have entered the cylinders as the valve stem seals would have prevented that (although it would have found it's way into the sump)"

What valve stem seals? There are none on the 1500.



"If it has entered the cylinders then not too much to worry about as the engine would simply suffer hydraulic lock and the starter motor would be incapable of turning the engine over."


Rubbish. I've seen it happen the starter spins the motor for a short period before the lock occurs and the result is a bent conrod.

Deborah Evans

Deborah,
I think I set that hare running about putting water in the oil filler cap. Re-reading Dave's description I think you are right. I was forgetting that the 1500 has a filler plug on the thermostat housing and this would indeed look similar to the manifold blanking plug.

I did say that he MUST remove the plugs before spinning the engine to clear water from the cylinders. I have had a hydraulic lock result in bent (later to break) con rod on a much stronger engine than the midget 1500. (as a result of a lake top-up day in Cumbria)
Guy

Guy I wasn't having a 'pop' at you. Given that water has entered the bores I'd want the head off to both check them and (if ok) clean them. The chances are there will be water damage to the bores/rings unfortunately. I've just done a 1500 that had water ingress into the bores and it was a rebore job.

I'd still be very worried about a bent conrod.
Deborah Evans

Deb, I didn't think you were!
I would agree the safe bet is a proper investigation. But if the water hasn't been in there for more than a day or so, and if the engine hadn't been started or spun after the accidental addition of water via the manifold plug, then he may have got away with it. I would probably clear the engine with plugs out, and then give it a try.

But you are probably right to play safe. A bent con rod would then break, and very likely then punch a hole in the side of the crankcase. Not a good outcome!
Guy

If there was enough liquid in the engine to lock it then how would it turn over a number of times?

I believe although I do not claim to be a super star that if hydraulic lock occurs with the engine stationary then removing the spark plugs would relieve the problem if however it occured as a result of water ingress with the engine running then anything may happen. However most cases of hydraulic lock are caused by a destroyed HG and manifests itself when the engine is stood for a while. The pressure built up in the cooling system whilst running bleeds water into the cylinder when the engine is turned off.


Only a week ago I saw an engine that was full of fuel/petrol that had locked due to the petrol in the cylinders. The owner was in a right state believing his engine had siezed. However it was as simple as a passing needle valve allowing neat fuel to run into the carb throat and into the cylinder the owner had left the ignition on with the fuel pump running. Petrol went everywhere on removing the plugs but the engine survived. It was an A Series in a Mini.
Robert (Bob) Midget Turbo

Unfortunately, given the nature of combustion gases being acidic and some being retained in the bore oil film, I've seen bores start to rust where water has been in them for less than a day!
Deborah Evans

Bob
I have seen A-series engine's survive the most terrible things!
Certainly the 998's those are almost indistructable (though i have managed twice)


Given the nature of the crank/rod combo on the 1500 I would certainly want to check those.
But as with the French revolution first "off with the head!!"
Onno Könemann

Maybe I shouldn't presume this, as I don't want to cast doubts about Dave's knowledge. But it seems to me that if Dave can mistakenly add water to the inlet blanking plug, then perhaps he doesn't have the experience to do a head job?

Perhaps there is someone in the area who could take a look at it for him?

Guy
(with apologies to Dave, as appropriate)
Guy

I often wonder that about a number of posters mate
Sadly it is a fact.
Robert (Bob) Midget Turbo

"If there was enough liquid in the engine to lock it then how would it turn over a number of times?"

Because it depends upon where the piston is relative to TDC vs the amount of water in the bore.

You don't have to have a bore full of water to cause a lock, a partially filled bore will lock after a degree of crankshaft rotation which the starter motor is quite capable of producing.


But then what would I know compared to all the internet 'experts', I merely build engines for a living.



"I believe although I do not claim to be a super star that if hydraulic lock occurs with the engine stationary then removing the spark plugs would relieve the problem if however it occured as a result of water ingress with the engine running then anything may happen."

See above! Also the fact that there is water in the bores for even a short length of time will mean that the bores themselves become damaged.


Deborah Evans

My MGB engine died around 11 years ago and I found No.2 cylinder full of water.

I finally pulled the engine recently and was amazed to find that it actually turned when I put a spanner on the crankshaft pulley bolt.
Dave O'Neill 2

To throw in a ha'pennys worth, I must agree with Guy that a head off job is something that he needs to get someone to do.

The engine that Debs was talking about was caused by someone putting the head gasket on upside down, which is slightly more critical on a 1500.

Please, take you car to someone who knows what they are doing and have it thoroughly inspected and assessed. It's fine to ask people on here, but, with the best will in the world, none of them are standing over you and watching, so, find someone who can and actually knows something.
rachmacb

Debs that is the whole point if there is enough water in the cylinder to cause hydraulic lock before TDC then it will effectively NOT turn over but will turn a few degrees and lock. In my extremely humble opinion this will not be enough effort or force to cause damage. A half turn of inertia built up by the starter motor ought not to be enough to cause any mechanical damage, would you expect it would?
Robert (Bob) Midget Turbo

This thread was discussed between 05/06/2011 and 07/06/2011

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