what should the compression on an hf crx be at?

 

The compression ratio, or the results of a compression test? If the latter, what were your numbers?

 

compression test, 120 psi

 

Thats too low, I like around 190. That's for mine, and I have no clue what engine you have.

 

an hf d15

 

Were all cylinders around the same number?

 

haha!!! let me check...if you can't tell, im in an impatient mood. brb.

 

Test the cylinders with all the sparkplugs out, using the same number of cranks for each cylinder (4-6), and make sure the throttle is wide open while you do it.

 

at 250rpm, wide open throttle

nominal - 185 psi
minimum - 135 psi
max. variation - 28 psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jlicrx &raquo;</TD></TR><TR><TD CLASS="quote">at 250rpm, wide open throttle

nominal - 185 psi
minimum - 135 psi
max. variation - 28 psi</TD></TR></TABLE>

250 RPM?

 

damn it! well the whole problem was, the car was bought and RUNNING! i decided to take the head off to replace all internal seals. i put it all back together and now it wont START! wow!..anways. cylinder #1 120 #2 150 #3 135 #4 ZERO! oh no!what should i do?!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">

250 RPM? </TD></TR></TABLE>that is what the manual says

 

would my car not start because of that? could this be possibly because of a bent exhaust valve?

 

or messed up valve seals

 

Cylinder 4 is not building any compression. I assume since you actually put the rings back on, it's one of the valves.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Fuzzy Rhubarb &raquo;</TD></TR><TR><TD CLASS="quote">or messed up valve seals</TD></TR></TABLE>

How would a valve seal effect compression?

 

Wouldn't a screwed up seal leak and cause a drop in compression?

 

did the car over heat or something why did u pull the head....... maybe you burnt a valve or cracked a ring or something my turbo zc had 195-1 190-2 195-3 and 0-4 i burnt a valve so id pull the head back off and relap the valves or check your piston rings out....

could his compression be way low if the timing is really far off.....

 

i doubt anything is wrong with the bottom block. damn exhaust valves had a crapload of carbon build up. it never overheated. i guess i have to just pick up a head from my yard.

 

The valves seal against the combustion chamber will, but not the valve seal.

Lol, kinda hard to explain. The valve's seal will effect compression, but not the valve seal.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">Lol, kinda hard to explain. The valve's seal will effect compression, but not the valve seal.</TD></TR></TABLE>
I know exactly what you mean. I don't know why I thought that. If the valve fully closed against the head, it doesn't matter about the valve seal. The compressed air would never reach it. duh

 

if it did have something to do with the exhaust valve, would replacing it with a new one solve it? also, what other model ef cylinder head can i swap out for stock features?

 

bump

 

Well if it was running before you took it apart, You had to have messed something up.
What exactly did you do and why??

 

well, it's now down to buying a used head that was running OR replacing the exhaust valves with new ones( if thats all it takes to seal it. )