Restoring the power of a 1986 110bhp XU92C engine

[missa91]

Yes but if it remains working like that, just wait. It is quite expensive to repair an engine. But anyway, there is the solution to buy another one and to repair it with time, then mounting it on your car.

I personally would like this very much... There is no greater you than hearing that engine running after restoring it for several months in the garage or basement. Truly a amazing experience.

[amilo123]

Yes but if it remains working like that, just wait. It is quite expensive to repair an engine. But anyway, there is the solution to buy another one and to repair it with time, then mounting it on your car.

I would like it also, but I can't really do that because I have no garage and live in an apartment.

I hope the valve is the problem, it is easier and cheaper to replace right?

[thefunkyboy]

If it is the valve, that's great and easy to fix. If it is the piston ring, it is harder.

Bay adding oil, the pressure increases => rings trouble. If not, a lack in valve etancheity.

P.S: on my GR with a XU52C engine, i got 8,5 bars. I put some oil and then, 12 bars... xD

[missa91]

yes. you need only a few gaskets, with the head gasket. new valves or better ones, for that cylinder and some abrasive paste to polish the valve seat on the cylinder head. this is the bear minimum. Also, you will have to machine the cylinder head once removed, because it will bend. If the valve seat is bad, then...

[missa91]

My engine is so bad that the ratios are around 8-8.5. But I don't even know what they should be.

[thefunkyboy]

If the valve seat is not good, just change the cylinder head. It is the same one XU52C, XU92C and GTI (excepted the cam shaft)

Missa => if it works and doesen't consume too much oil, that's ok. Mine was consuming like 1L of 20w50 each 800km

[amilo123]

My engine is so bad that the ratios are around 8-8.5. But I don't even know what they should be.

from what i know, all should be above 10, and between them no more than 20% difference.

[missa91]

since i started using LukOil oil from the gas station it uses about 1l every 1700km. but when I used some Castrol GTX it was like 1l per 1000km. The same type and grade: 15w40 mineral.

Amilo123, I truly hope you resolve this problem, and am always glad to help in any way possible.

[alargeau]

The compression ratio should be 13 with a 0,5 bar difference. But what matters is not the compression ratio you get, because when the engine has a high mileage, it's totally normal that values go down. What matters actually is the difference between values. If for instance you have 10-9,5-10-7, then the "7" value is the problem.

[amilo123]

The compression ratio should be 13 with a 0,5 bar difference. But what matters is not the compression ratio you get, because when the engine has a high mileage, it's totally normal that values go down. What matters actually is the difference between values. If for instance you have 10-9,5-10-7, then the "7" value is the problem.

measured cold or hot?

[alargeau]

Engine must be hot.

[alargeau]

So did you check the compression ratio today?

[amilo123]

yes, so i first did will cold or a bit warm.

all are ok at 14, except 3 which has only 9... then i put some oil in 3,.did the test again and it passed 16 lol.

i put all of them back, and then warmed the car. It took a while to burn the oil. Then I didn't do the test warm because there would have been to much smoke and the neighbours would complain...

but I think that i found the problem. the piston ring right?

[thefunkyboy]

I guess too

But if the car works correctly with that, you can continue using it

[amilo123]

it runs well but i feel the missing horses... it is the same as a 1.4 logan now lol. I don't really like that:)

My plan is in june to replace the clutch and the exhaust manifold and ask the mechanic about this cylinder to see how much would it cost. At least now I now the problem. The list of problems is kinda getting bigger. But not too long, for now.

meanwhile i am thinking of putting some xado revitalising gel in the oil. What do you think of it?

http://www.xado.co.uk" onclick="window.open(this.href);return false;