I don't have a tach so I don't actually know the rpm that was at but I did the check with all the plugs out at the same time and a strong newer battery.
The engine smokes pretty bad at times so I was beginning to suspect the rings, and I thought maybe a compression test would tell me something. It also has a massive oil leak (I lose a quart about every 25 miles). So I'm considering taking the engine out and doing a rebuild, just can't decide if I'll be able to do it myself or not...
theres no need to do a WOT test. The WOT compression test goes under the premise that without the throttle plate held wide open, you won't get a full air charge into the cylinder for it to compress. However, when cranking the engine, the engine rpms are hardly enough to register as a twitch on your tachometer. At that RPM, the throttle plate is open enough for the engine to start up, which is all you need for a compression test. WOT is unnecesary. You may see the compression come up with fewer cranks, but your peak compression won't be any higher or lower if you crank it till it peaks.
Now as far as a wet test, you may get some higher numbers with that.
When you say that your engine is going through a quart every 25 miles, is that leaking or is that burning?
i had the problem of my engine smoking and it needed a rebuild but it was making a horrible tapping noise from the piston going to far up and down. it took me 8 hours to take the engine out and put it back in. i only needed a few sockets and spanners didn't need engine crane cos the engine only weighs 60 70 kilos and i just lifted it out by hand.
It is doing both but I'm pretty sure most of the loss is from leaking. However it does seem to smoke worse every day. I've only put 100 miles on it since I got it and when I got it there were no problems (that I knew of) except a fair oil leak.
Oh, and now I am leaking gas, too. It leaves a puddle wherever I park it. I think the tank has rusted through.
Those numbers are low but the really telling part is the difference between cyl. The difference should be 10% or less which yours is not. The oil loss is probably from blow -by. Try a wet [little oil in each cyl] compression if you get a fairly large rise the rings are leaking in that cyl also if not probably a bad valve. bottom line is at least a rering and head work.
with any luck its just the rings. You need to check that fuel leak out though. It may be something as easy as cracked hose to the fuel filter. Check your fuel pump too while your checking stuff. If it's dripping fuel out the bottom drain of the pump then the diaphragm is ruptured and you could be getting fuel into your oil. This will damage your seals and break down the oil. It will destroy your engine in a big hurry. Since you mentioned it was running fine when you got it, I just thought I'd throw that out there as something to look at as far as a possible cause for advanced engine wear.
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