Rb25Det Compression Results

[juicy3]

Hey Guys,

Did a compression test today on my r33 and was Pretty happy until the 6th piston (closest to driver)

Here were the results

1 - 150

2 - 152

3 - 156

4 - 155

5 - 150

and then (

6 - 90

put about 5 - 10ml of oil in there and it only went up to about 93 (

Not too happy with that

Could anyone shed some like on what might be wrong and ways to go about fixing it??
I do have a video of the tests if they are relevant to anyone?

Thanks Guys
Josh

[GTSBoy]

Um, it's broken. Take it apart and fix it.

Oil didn't help so the problem is either a broken piston or something wrong in the head (like most females). Burnt valve etc.

[SargeRX8]

Maybe you could be hopeful, somewhat, and hope for a slightly damaged head gasket in cylinder 6. Before pulling it apart you could do a leak down test. That will tell you if its the head or your piston and if it is the head, is it the intake or exhaust valve.

[GTSBoy]

How does a leakdown test tell you the difference between any of those? Best I can tell all it tells you is that X amount of air is getting out.

[WMDC35]

haha, yeah something wrong in the head is no fun!

[SargeRX8]

How does a leakdown test tell you the difference between any of those? Best I can tell all it tells you is that X amount of air is getting out.

If you hear air gushing out of the exhaust you know you have an exhaust valve issue, if you hear air gushing out of the pod filter you have an intake valve leak, if you hear air gushing out through your dip stick or it pops out, then the seals or piston are at fault as air is getting past them and pushing the dipstick out. If the air is leaking from a leak down test where is it going? Where ever the problem is, that is where the air will be coming out from. Its pretty simple.

[Joshbigt62r]

SargeRX8.

I was also taught that procedure. ^^^

[juicy3]

Yeah i probably should have mentioned that the reason i did the test was because the dipstick was popping out, haha so piston or seals?

Guessing this mean rebuild or new engine -.- or rb25/30 conversion haha

Anymore thoughts guys?

[GTSBoy]

Sarge,

Yeah, I'll switch my brain back on now.

[Joshbigt62r]

Haha GTSBoy I thought you must have been having a memory blank! As your one of the most informative guys on this forum.

[On p's]

yea defs rebuild mate! or cheap option buy 2nd hand engine

[SargeRX8]

2nd hand engine. Much cheaper and so long you don't find a dud you'll be sweet.