8 replies to this topic

[JEFFtheJ00la]

i did a compression test today on my 84 1.3 crx. i figured it had a blown h/g from symptoms and when i took the spark plug out the 3rd one from the cam gear was bridged with crap and soaked in coolant. anyways, the nukbers are

starting at the cam gear: 210 195 165 205

i was wondering if compression readings in the 200's are high? ive always heard of 150's and 160's. the si i did the other day had only 150 for its highest reading. the engine has 174k on it and before i parked it it used about a quart every 100 miles.

[xfurb]

The high numbers aren’t as much as a concern as the span between them. 200ish on 1,2,4 and 165 on 3. Not good.
The bridging on number three; was it black oil crud? That explains the quart every 100 miles.
One way of checking whether its valves or rings is to pure about a tablespoon of engine oil into each plug hole, and rerun the compression test. Higher numbers, as in 10-20 psi even more, would lean towards worn rings.(174k you’re going to see that) Little change tends to show that cylinder burns a lot of oil and the numbers you’re getting is because of a broken compression ring, leaking valve guide seals, and on the aux valves the o-rings are leaking. (the 1.3 had that little aux valve... right?) Oops and a bad head gasket. That’s because the rings have already cold sealed with oil/water. A bad valve seat acts like a “no change condition” but the bridged plug, burning oil, and 165psig says its not.
You said “soaked with coolant” Is it moisture or green stuff? Why I ask is a bad head gasket usually doesn’t get such a high number 165. I was lucky to get 40psig. Course I had water/coolant in two cylinders.
A cheesy test I use to verify how bad a water leak is to pull all plugs, should be already done ‘cause of the compression test, and crank the engine. Bad water leak sprays coolant all over the place as long as you crank it; little moisture, spits a little then is dry.

Dam it! I just reread your post. You asked “is 200 high." No. my Stock 1.5 DX is about there. and I think the 1.3 is a higher comprestion engine. Sorry ’bout the long useless post... bored at work.
~dan

[Ghost-One]

you wont know till you pull the head do it up jewlery boy
ps thank you for the ring sizing

Edited by Ghost-One, 28 December 2005 - 01:30 PM.

[toxicshit]

drop a little oil in the last cylinder and run the test again..it it stays good with the oil in them , then the piston rings are bad.

[JEFFtheJ00la]

i know about the wet compression test. i know 99.99% its a bad head gasket.when i cranked the engine over coolant definately came out. it wasnt a alot, but it diddnt dry quickly. my dad and i argued whether or not the smoke was blue or white. the plug is gapped with greenish stuff, definately not oil. i think i probably have an oil leak or 5. i was actually suprised that the plugs looked so good except that 160 guy. i really expected lower numbers since the si i did was way lower. the car did run until the plug bridged on me when i was on my way home from work. i had to drive home in 3rd to keep it going. now i just have to decide if im gonna use the si head or the head thats on there since the numbers are so high on the other cylinders. i dunno.

[1stGenRex]

1 quart every 100 miles!?!?!?!?
are u running a 2 stroke!?!?!?

[JEFFtheJ00la]

no its called im running a car i paid 300 for that was wired with extension cords never had a gasket changed and i ran the hell out of it for 1000 miles or more in my backyard on my figure 8 track. im sure it leaks

[xfurb]

Defiantly pull the head off, maybe check the head for a crack. The couple of bad gaskets I’ve seen have always blown to the adjacent cylinder.

[JEFFtheJ00la]

we got the head off tonight. i found that two of the combustion chambers next to eachother have v shaped cracks in them. i take it thats not good. the cam also looked pretty narley. discolored and rough in some spots. it doesnt suprise me though because its been run low on oil and hot a few times. the bottom end looked beautiful. alot better than the si i took apart the other day.

i noticed my pistons were stamped hf 1.3. i was under the impression that my crx was a 1.3 (not even sure if there is a difference now) because the chasis code says its not an hf but it has a shift light.