Cylinder Issues

[baker240]

Hi all, I'm looking for some help. Today after many months of trying to get my moggy up and running I decided to call the RAC and get it going. It was a success and the car now starts. However, the engine is running badly and he advised me that the 2 cylinders nearest the radiator are working but the other 2 are not. He suggested that this could be due to the head gasket being blown or the engine might need a rebuild/replacement. I hope that by changing the head gasket will rectify the problem. I am happy to do this myself. If this does not solve the issue and I need to do a rebuild could someone give me some info on what that would involve. Is this a case of taking the engine apart, cleaning the parts then putting back together or do I need to purchase engine parts? If so, what would I need?

Thank you in advance for your help.
Chris.

[philthehill]

I would suggest that you get a known running engine and do your original engine in slow time.
These are some of the things you may need to do but all will be dependent on what you find on dismantling the engine.
Remove cylinder head and examine gasket, top of block and cylinder head face for damage.
If all ok -
Decoke head and grind in valves - fit new valve springs, seals and gaskets.
If face of cylinder head is not flat -
Skim cylinder head.
Examine top of block.
If not flat or has incurred blowing gasket damage -
Skim top of block.
Check bores for wear.
If more than just piston rings required -
Re-bore cylinders.
Fit new pistons and rings.
Examine crankshaft
If more than just shells required -
Regrind crankshaft and fit new under size shells.
Rebuild engine with new timing chain, seals and gaskets.
The above is not exhaustive but you will get plenty of help on here - all you have to do is just ask.
Phil

[les]

Rebuilding an engine is done to replace worn or faulty parts. Dismantling cleaning and putting back together will achieve nothing. However when doing a rebuild cleanliness is an important part. Try the head gasket first, making sure the head and block surfaces are perfectly flat with no hollows between the cylinders, check the valves are seating properly, and of course fit a new gasket with a smear of grease. Worry about a rebuild if that fails to improve things.

[les]

Oh well you must have posted whilst I was typing Phil!

[bmcecosse]

I would try a compression test on the cylinders before rushing in to a gasket job. And check/set the valve gaps first. Are you sure the HT leads are on right order - 1342 anticlockwise round the dizzy cap. What did the RAC guy do to get it going?

[baker240]

I would try a compression test on the cylinders before rushing in to a gasket job. And check/set the valve gaps first. Are you sure the HT leads are on right order - 1342 anticlockwise round the dizzy cap. What did the RAC guy do to get it going?

Hi, thank you for your reply. The RAC chap removed the distributor unit, took it apart and found that the small springs inside had come loose meaning the metal parts had basically become bent. This in turn meant the back plate was not sitting flush so the timing was shot to bits.

You mention carry out a compression test? What do I need for that and how do I carry that out?

Thanks again,

Chris

[baker240]

I would suggest that you get a known running engine and do your original engine in slow time.
These are some of the things you may need to do but all will be dependent on what you find on dismantling the engine.
Remove cylinder head and examine gasket, top of block and cylinder head face for damage.
If all ok -
Decoke head and grind in valves - fit new valve springs, seals and gaskets.
If face of cylinder head is not flat -
Skim cylinder head.
Examine top of block.
If not flat or has incurred blowing gasket damage -
Skim top of block.
Check bores for wear.
If more than just piston rings required -
Re-bore cylinders.
Fit new pistons and rings.
Examine crankshaft
If more than just shells required -
Regrind crankshaft and fit new under size shells.
Rebuild engine with new timing chain, seals and gaskets.
The above is not exhaustive but you will get plenty of help on here - all you have to do is just ask.
Phil

Phil,

Thank you for you reply.
It seems pretty straight forward but if I could just ask you to expand on the following should I need to do it:
How would I "skim" the cylinder head?
Re-Bore the cylinders?

Thanks again,
Chris.

[philthehill]

Skimming the cylinder head and re-boring are specialist jobs that would have to be carries out at your local and reputable engine reconditioning company.
To check the compression a good basic check is to use the starting handle to turn over the engine - if you get no resistance on one or more cylinders that does mean the head off for further examination.
The better way is to use a engine compression tester (see example below) which is inserted or screwed into the plug hole and the engine turned over on the starter with the throttle held open. The readings for each cylinder recorded and compared.
Put a few squirts of engine oil down each plug hole, again turn the engine over and record the new readings for each cylinder.
If there is considerable difference between dry and oiled readings that is a good indicator that the piston rings are shot and need replacing.
Some do the compression test when the engine is hot but if you have poor compressions those poor compressions will show up whether the engine is hot or cold.

http://www.ebay.co.uk/itm/Draper-37442- ... Sw7ThUp9h-

Phil

[Mark Wilson]

Although I'm sure the RAC man had reason to suspect a blown gasket, it would be wise to try a new or known good distributor before going much further.

[baker240]

Skimming the cylinder head and re-boring are specialist jobs that would have to be carries out at your local and reputable engine reconditioning company.
To check the compression a good basic check is to use the starting handle to turn over the engine - if you get no resistance on one or more cylinders that does mean the head off for further examination.
The better way is to use a engine compression tester (see example below) which is inserted or screwed into the plug hole and the engine turned over on the starter with the throttle held open. The readings for each cylinder recorded and compared.
Put a few squirts of engine oil down each plug hole, again turn the engine over and record the new readings for each cylinder.
If there is considerable difference between dry and oiled readings that is a good indicator that the piston rings are shot and need replacing.
Some do the compression test when the engine is hot but if you have poor compressions those poor compressions will show up whether the engine is hot or cold.

http://www.ebay.co.uk/itm/Draper-37442- ... Sw7ThUp9h-

Phil

Thanks Phil.

I will carry out as you describe and then report back my findings.
Thanks again.
Chris.

[bmcecosse]

I'm 'dubious' about the RAC explanation....the little springs are most unlikely to come off except by human interference - and even if they do - nothing will be 'bent'. I suggest an element of bull droppings going on there... The idea of doing a hot compression test is to make sure the oil is easy flowing - and also to make sure the battery is well charged. Sure enough a cold test will show a blown gasket - but a hot test is much better from a general engine condition point of view. I suggest from your questions that an engine overhaul may be quite an adventure for you - and if there is more than a blown gasket involved here, I think you would be better off looking for another engine to swap in to the car.

[baker240]

Afternoon all,

I have fitted a new head gasket as the old had blown and this has solved the problem with the cylinders. However, from the attaced photo I have a very small water leak on the top of the nut and around the area shown. I have torque the head down to 44 as per guidelines. What should I do now??



Thanks[frame][/frame]

[philthehill]

Do a heat cycle and re-torque.
If still weeping after re-torque & you do not want to remove the head and skim the head to block face get a bottle of Bars Leaks put it into the radiator and run - whilst not a perfect solution it may solve your weeping solution whilst you decide what to do next.

http://reviews.halfords.com/4028/719120/reviews.htm

Phil

[bmcecosse]

The stud must be 'not tight' in the block. Try as Phil describes - otherwise - with a stone cold engine - undo that nut, and then with two thinner nuts locked together - screw the stud firmly down into the block - then refit the correct nut and tighten to 44. This is 'not perfect' either - but the alternative is to completely remove the head again - and tighten it - so I think it's worth a try.