I finally picked up a compression tester over the weekend... here are my results.

220 - 215 - 215 - 220

Not bad. I cranked over 5 times as the instructions stated, but the third cylinder read 190 after 5 cranks, so I cranked 2 more times and it read 215.. Hopefully this doesn't mean its bad.
Also, I heard loud POPs while cranking over.. is this normal? Andy feedback welcome.

 

bump

 

I learned in class that your supposed to crank all cylinders 4 or 5 strokes. But to crank all cylinders with the same amount of strokes. Anyhow, how many strokes are you guys out there cranking your motors when compression testing?

 

ive always cranked 8,9 times per cylinder. I was under the impression you are at least sposed to do it ~5 times but could crank more. am i wrong?

 

good compression #'s.

 

I always thought that you were supposed to crank until the gauge stablized @ a single pressure.

 

Anyone try that oil additive stuff that is supposed to bring compression close to normal? In the ad it had one cylinder that was at like 50 and brought it back to like 200. I see it in magazines and in autozone\pep boys.

Sorry to thread-jack boss.

 

i always just crank it over untill it goes no higher... thats what i have always done

my results on my b18c are 245 238 240 245

 

Anybody else get the loud poping noise while cranking over? I hope I didn't damage anything.

 

i was testing my gsr engine today and i was getting the popping too. Never heard it happen any other time. I thought it was the guage wacking somthing as it jumped, maybe not.

I usually just do 7 cranks, i think i read that somwhere. I was watching the guage and i think btw 5-7 cranks and it just pretty well stabilizes.

I wouldn't get too excited about the peak numbers over the consistancy of them, which is more important.

I was getting 185 - 190 across the bank, then i used my other guage and got 205 - 210. that guage always reads 15 psi higher.

My b20 (9.2:1cr i think) got not much lower than those numbers, so i was a little worried. But i believe that when these engines start to wear, its the middle cylinders that drop first. If the numbers are consistant, then its probably healthy.

btw my gsr is a jdm 10.6:1 beast

d

 

and i just remembered that i forgot to open the throttle while i did it this time. start over. frig man, how long have i been doing this?

d

 

What do you mean by open the throttle? I don't remember seeing that in the instructions...

 

ok, that's better. 220 +/- 3psi right across with my low reading guage. that would be more like 235 - 240 with my other one.

gotta step on the gas pedal to open the throttle body to actually let some air in mr.

d

 

yea of course I stepped on the gas pedal, how else do you turn the engine over...

 

you need only to step on the clutch and turn the key to simply turn your engine over. Never step on the gas when starting it

d

 

they aren't talking about starting it, they are talking about doing a compression test, completely different man

 

You are right... I didn't touch the gas pedal.. I don't know what I was thinking when posted. I just used the ignition key while pressing the clutch.

 

kay, good. try it again and either jimmy the throttle plate open or step on the gas to the floor. dont forget the unplug the fuel injectors

d

ps I was worried that you must step on the gas everytime you start it if you thought you needed to just to turn it over. Can't remember why its "bad", other than you could flood it perhaps.