Restoring the power of a 1986 110bhp XU92C engine

[missa91]

I thinks it was obvious there are two needed But I am not sure that he needs to press the pedal. And the reading is taken in one, maximum two cycles of the cylinder going down and up, so fuel flooding isn't any problem, by the way, when all four spark plugs are removed, the fuel will went quite fast.

I honestly don't see the difference in pushing the pedal, because there is no relation to the compression ratio.

[beni]

I never tried without pressing the pedal ... so I do not know if that changes anything ...?

[missa91]

Think about it a little bit. There are 3 ports per cylinder. One for exhaust valve, one for intake and for the spark plug. you measure at the spark plug. the valves do their thing, but the gas exchange is the same if there is more or less fuel, because the volume of fuel injected is small compared to the volume of air and volume of each cylinder bore.

He just needs to take out all spark plugs for the engine to turn lighter and quicker, so the measurement takes a little while.

[amilo123]

I haven't tested the compression yet, but in the meantime I tried something different...

With the engine running, I removed the cap where you put the oil, and I felt a lot of air pulsating. Then I asked a friend to rev the engine to 3000 rpm. I saw exhaust fumes come out.

Is this normal? Especially when idle...Should air and fumes come out of there at that rate when idle?

[missa91]

Not as much. Fumes there, especially when great indicate that your engine is burning oil. Is it smoking blue when you rev it in place? This is even a further reason to check the compression ratio.

[alargeau]

Oh oh oh, it seems your car consumes oil... Was the smoke blue?

PS: it seems Milos was faster than me!

[missa91]

No,no,no I'm studying...

[thefunkyboy]

It may be a trouble with the piston's rings. The only solution is to test your compression and if bad, you just put some oil by the spark hole and then try again.

For example, if the result was 8 bars and then, it is 12 bars. Your piston rings are in bad state. But if it remains 8 bars, it may come from the upper side of your engine (bad valve etancheity)

[alargeau]

(bad valve etancheity)

Chris, your girlfriend just phoned me and she told me to tell you to go to bed, you invent words!!

[amilo123]

the smoke was blue I think...and it smelled like it was coming from the exhaust.

could this be one of the reasons it smells like exhaust fumes in the car?

[alargeau]

Oh you need to be very careful because you're engine is telling you "I need some attention". Test the compression ratio as Chris told you and you shold be fixed after that.

[missa91]

Maybe it's the burnt oil smells or your exhaust manifold. But the blue smoke is the problem. Do you need to top up your oil? If yes, how much?

[thefunkyboy]

(bad valve etancheity)

Chris, your girlfriend just phoned me and she told me to tell you to go to bed, you invent words!!

loool, that is so true, I am totally tired

If it smells exhaust gaz, you may check for leaks from the valves.

[missa91]

bottom line, if he can't live with the fumes and the lack of power, he should open the engine and do what needs to be done

[thefunkyboy]

Yes but most of the time, by opening your engine, you discover a lot of bad things

I am repairing a XU9JA and I got some suprises... A saw broke on the engine block, trouble with two pistons rings, etc...

Sometimes, it is better to find another engine, to repair it and to put it directly on your car when finished