I have a mk1 1.8is however the engine is a mk2 1.8 engine.
For a few months I’ve struggled with burning oil and noticed quickly the 3rd cylinder spark plug was wet with oil. I have since changed the cam cover gasket twice (in case I somehow did it wrong the first time), using original mazda gaskets. Despite this, I’m still burning oil. Is there any other way oil could be leaking into the spark plug well, also am I correct to assume the oil in the spark plug well is the cause of my oil burning issues? I could just be a moron and somehow messed up the replacement of the gasket twice (despite the fact I’ve done it plenty of times before).
Appreciate your knowledge, Sam.
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Sam, can I ask what lead you to think changing the cam cover gasket may cure the oiled up plug ?
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Sounds like a broken oil ring in number 3 cylinder. Get a comprestion test done. This will tell you if it’s rings.
If the oil is in the well (as the OP says) then it’s not getting there from the cylinder. The fact that it is burning oil too may not be related.
I would be looking at the PCV system first. Excess crankcase pressure could cause both issues.
I think we need a little clarification here. Is the ‘wet with oil’ on the outside of the plug or on the electrodes when you take it out?
Burning oil and oil in the spark plug well are two different things with two different solutions.
The “wet” plug I’m referring to is outside the plug and not the electrode. I was worried that the burning oil issue could have been separate however i think I had a naïve case of knowing I had an issue and seeing something wrong so I assumed they were related to the same thing. What are the first actions I should take and are there any other symptoms I should look out for in order to narrow down the issue? (Sorry if that is too broad a question as I’m sure there’s many possible issues)
Check the PCV system, as above.
It sounds like a topical Mk 2 1.8 engine that as over the years ran out of oil and filled back up again, its getting past the stem seals from being really low with lube and metal to metal resulting in worn stem seals , these engines from new had a trait of using oil from the factory, the harder its used ,the more they will use , unfortunately owners were/are butting their faith in a false oil pressure gauge that you may as well rip out and put a LED that lights up with the ignition for what it does, plus the fact it really is not a indication of the oil level, people need to check under the bonnet and use the dip stick , its the only way.
The 1.6 MK 2 was not affected by this , just the 1.8 Mk 2 1998-2001, its a great engine and will last a long time if properly checked, this was an issue and mazda released the 1.8 VVT engine from 2001 because of the lack of awareness that owners were not checking and engines running out of oil and seizing.
So when the internet of many wonderful bent information is spread easterly about this mark 2 and the MK 2.5 1.8 versions, it was not a cosmetic change to the 1.8, so far from it, it was a different car ,but the 1.6 MK 2 to MK 2.5 was a cosmetic change.
The 1.8 MK 2 engine is a great engine if looked after correctly by knowing its traits , as all the Marks have their traits.
M-m
Yes I’ve been very careful to very often check my dipstick and never even look at the gauge on my dash (in fact I’ve looked into how difficult it is to replace with a functioning gauge).
If my stem seals are worn that sounds pretty serious, how would I check that issue specifically?
Worn stem seals usually give a brief puff of blue exhaust smoke when you come back on the throttle after changing gear. Harder to see on a modern car with a catalyst in the way. Again, any oil use will be aggravated by excess crankcase pressure, which helps push the oil into the cylinders past the valve seals, as if the intake
vacuum weren’t enough.
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I know some will call it snake oil but I have had good results with Sea Foam.
Pull the plugs - Put the pistons half way up the bores - put 60ml of sea foam in to each cylinder.
Put plugs back to stop it evaporating - leave for a few days to allow the sea foam to seep passed the rings and free them up.
After a few days - remove the plugs - turn over the engine to ensure no liquid is still in the bores ( it should all be gone )
Replace the plugs.
Put the rest of the bottle of sea foam in to the fuel tank.
Start car and take it for a drive.
This has reduced oil use on a few old cars over the years.
I wouldn’t have thought that valve stem oil leakage or worn oil control rings would result in oil in the spark plug well. If you are still getting oil in the sparkplug well after changing the cam cover gaskets you may need to check the sealing face of the cam cover and the mating face of the cylinder head for damage that a new gasket will not seal.
“Burning oil” will be a separate issue and as others say can be caused by worn piston oil control rings, worn valve stems or the PCV system.