Morris Minor Owners Club

Hello all,
I suspect I may have a blown head gasket, Ive got oil in my water and a few bubbles in the dipstick, and mayonaise in the oil cap.
How easy is a head gasket change and any things i should be aware of.
Thanks
Mark

On a Minor mayonaise in the filler cap is NOT neccessarily proof
of a blown head gasket. Unfortunately oil in the radiator and bubbles
ARE. If you haven't done this job before I would only attempt it
with the help of someone who is experienced.

Certainly sounds like it!

Not too difficult, but if you read the manual and follow it carefully you should not have too many problems.

Getting the head off might be awkward but don't be tempted to shove a screwdriver in as this will mark the faces.

While the head is off, check it for distortion either by taking it to a machine shop or by using a flat piece of glass and seeing where it touches.

Make sure that you clean and prepare the block and head faces so that they are perfectly clean - without dropping any bits into the bores (especially down the side of the piston).

Also, a cleanup (decoke) of the head would be advisable while you have access to it. And make sure that you do the head bolts up in the correct sequence to ensure an even take up.

Once you have torqued the head up and you have had the engine running re-torque it again after about 50 miles or so.

Also, it goes without saying, renew the oil and filter and flush the radiator and refil with water & antifreeze / summer coolant mix.

I've seen oily looking stuff in a few radiators and it wasn't always the headgasket.
Mayonaise in the rocker cover is normally a sign of poor servicing and blocked breathers.

Is the mayonaise and oil in the water a recent thing?
Have you noticed any difference in the way the engine runs?
Does it loose huge amounts of water?

In basic terms, if you have an imperial socket set, a torque wrench, some screwdrivers for the hose clips and feeler guages to re-set the rockers, you can do a head gasket, BUT the headgasket is not a good job for a novice.
Could you cope if one of the engine studs broke off? Would you know enough to check the condition of the head when it is off? Would you roll your eyes and laugh if you put it back together and the darn thing leaks water everywhere?

Hello,
It is not losing much water at all , if not a head gasket what could it be.
mark

I have seen emulsion in the oil due to condensation / being left over winter in the damp which tends to clear up during the summer, but oil in the water is usually an indication of a blown head gasket.

I would check to make sure first though, as you don't want to take the head off to find a perfect gasket!!

Are you getting lots of oil in the water and vice versa?

Hello,
I dont know about a lot of oil , there is a bit in the water, when you remove the rad cap it does smell of exhaust, i take it doing a compression check will help, will it be okay to drive till the weekend as i do need the car for work. The water is sludgy but oily when rubbed on fingers.
mark

Do you know if the cooling system has been flushed in the last few years?
Some minors have not had their cooling system flushed for 10 or 20 years, which will look a real mess.
What can happen is someone put grease on the hose joints to re-assemble them, which ends up getting flushed round until it sits on the top of the rad water (and can also ruin the hoses)

It is not losing much water at all

How much is that? A pint every 100 miles or every 10 miles?
If it is every 100 miles, don't worry just yet, but keep a very close eye on it until you can get it looked at.
if it looses a pint or more every 10 miles it needs looking at very quickly.

Hello
I think i`ll flush it first and see what happens, its only about 2 inches below the neck.
mark

I would recommend Bars coolant flush as I tried lots and that was one of the few that seemed to do something.

Be careful when flushing the radiator if you are losing a bit of water. I tried it on a car and it must have flushed out little bits which were plugging some leaks so the water loss got worse.
The good thing is that I had to sort the cooling system out properly so now it's perfect, but if you need the car for work make a contingency plan.

Agree with the last point - but a good flush of the cooling system can work wonders .... I had a Lancia once that was overheating (suspected head gasket problem). When I started to drain the water it wouldn't come out until I had cleared the blockage - after that no overheating.
If you are worried about flushing out debris which is sealing potential leaks, then buy a BAR sealer as well as the flush. If you do get a leak subsequent to flushing the BAR sealer will probably fix it. It's a good thing to have in the garage anyway - just in case!
Good luck.