Morris Minor Owners Club

Funnily enough that car had regular oil changes with Castrol GTX!

How would i test for oil getting past the control rings.Also would it be likely that these two pistons would have the same problem and the other two to be fine

Darren. wrote:Update....I decided to take the rockers off and inspect. I slackened the head off in bolt order. Taken the rockers off and found it was all clean and ckecked all the oil holes to each rocker which were good. I think i was just being paranoid about lubrication ERRRR maybe lol.

Now for the bad news. I realised that slackening the head bolts might cause the gasket to fail but i took the risk. Taken the car for a run to set the timing and fuel mix. The car ran ok ish hah hah but not quite right. Brought the car back home and inspected the plugs. Plug 1 and 2 was a great coffee colour but plugs 3 and 4 were black GRRRRRR. Decided to do a compression test and found plugs 1and 2 were round 170 but but plugs 3 and 4 were quite a bit higher which leads me to think oil is seeping throgh the gasket. So looks like my new gasket is toast.

Possible bad news, undoing all head nuts, but if the head was left undisturbed and water was drained down, the gasket should not have been disrurbed. Depends, perhaps, by what you mean by ''slackened'' as well.

So numbers 1 and two recorded 170 psi for compresion test. That is OK. Clearly not a lot of bother if 3 & 4 were even better!

Oil will not 'seep through the gasket' into two cylinders - I'm guessing there is no oil pressure for that (top end lube is usually pressure, or flow, restricted in some way) and the cylinders are operating at around 700psi on one stroke of the four and a couple hunded on another, so compression would be more likely to drive gases in the opposite direction.

Re plugs - there is a clear difference between oil fouling and over-rich mixture (or poor combustion). Which were yours - sooty or oily? Are the plugs all the same grade? Perhaps try those plugs in numbers 1 & 2, to see If the problem stays with the pots or moves with the plugs? Are all the plug leads the same and in good order? Leakage between them is a remote possibility (and even remote possibilities should not be overlooked, even though some on here ignore all but the obvious).

How well was it running? Not on two cylinders only? Plug leads in wrong order?

I don't think the head gasket is the problem. Might even be worn cams on the distributor meaning a weak or intermittent spark, or even the distributor cap leaking between the two HT outlets

I'm not really sure how much 'splashy' oil is usual for the rockers. Certainly there should be some oil thrown around at high revs, but there is not a lot needed to keep things lubed (old engines, admittedly running at less rpm but with no top end lube at all were oiled or greased about every 8 hours of operation). Overhead cams are literally bathed in oil, but rockers are rather less demanding.

So, rocker lubrication aside, unless you confirm it is definitely oil fouling, I reckon you more likely have an ignition problem.

RAB

OLIVER90 Thank you so much for your advice your a big life saver.New dizy cap and rotor arm. Jobs a good un. I was about to take the head off and feeling very sick about the whole thing.Feeling on top of the world once again