compression problem

[cococola]

Well just when I thought my problem list was getting shorter on morris I have carried out a compression test tonight with the following results...
cyl 4=120 cyl 3=120 cyl 2=40 cyl 1=40
so 1 and 2 are very low.
This has seemed to happen very suddenly and coincided with my new distributor change...Just coincidence or am I still missing something?
The car did stand for 3 weeks aswell previously and caused no problems up till then.
Any advice would be greatly appreciated many thanks.

[chesney]

Head gasket one between 1 and 2 it seems. The rest doesn't look great either, was this on a cold engine with the throttle closed?

[cococola]

when engine was cold and also ran up warm, I don't appear to loose much water or engine smoke

[IslipMinor]

Check the valve clearances before repeating the tests.

Compression tests should be with the engine at normal running temperature, all plugs removed and the throttle held wide open.

Once you have done these again, as a secondary test squirt a small amount of oil into the cylinder to be tested and repeat the tests. If the 'wet' tests shows much higher pressures, it would suggest that the rings are the problem. If the 'wet' results are similar to the 'dry', then either valves or head gasket. With 2 very low side-by-side results it very much looks like a head gasket problem, but worth doing the other checks first.

[bmcecosse]

With these readings it IS a blown head gasket. Don't run the engine again! By all means check the valve gaps -but if they are ok - just lift the head.

[cococola]

The tappets are a bit rattily..could this cause compressions low and my chugging?

[simmitc]

Not those readings. As Roy says above, it IS a head gasket blown between 1 & 2. Do not run the engine or it will be not only rattly, but in need of a skim of both block and head - at which point you might as well do the re-bore and full reconditioning. If you change the gasket before you do any more damage, then you may get away with running the engine for quite a few thousand miles more.

[bmcecosse]

Just lift the head!

[cococola]

headgasket kit just purchased

[cococola]

Well head is removed this morning and between bore one and two the gasket is missing/broken.

[IslipMinor]

Apart from the obvious of making sure that both the block and the head have not been damaged by the failed head gasket and both cleaned up to remove any burn marks, I would double check the timing as in the first post you mentioned replacing the distributor. How did you set it with the new distributor?

After that, replace the head and torque down, re-torque after the first heat cycle and check tappets. Worth re-torqueing again after a few hundred miles, just as a final check.

[cococola]

I replaced the headgasket today and Morris fired up first time on all cylinders...Im so chuffed
I just need to reset the tappets tomorrow and hopefully all ready to drive again.
Thank you everybody for the wealth of information and help to complete this.

[bmcecosse]

Remember to retorque it 44 ft lbf after the first heat cycle.. And then set the valve gaps.

[cococola]

will do Roy . Many thanks

[The vast minority]

What a happy ending
Glad it's sorted.
Al

[cococola]

Just been for a spin after setting tappets and a little tweek with tickover and everything runs beautifully.
Regarding head retorque....should I do this after a certain mileage and hot or cold engine?
man thanks.

[bmcecosse]

After the first heat cycle!! And let it cool - but not necessarily stone cold...

[simmitc]

Then repeat after a few hundred miles, just to be sure. Probably won't need doing, but I have known an extra half a turn required on a couple of studs; and better safe than sorry.

[bmcecosse]

I never do that - just asking for a snapped stud...... I just leave well alone after that first cycle. Never been a problem!

[IslipMinor]

I agree with the final check after around 100/200 miles - never snapped a stud doing it!