OH NOES! MY Rb25...

[DeformityX]

K so here's the deal, Took my RB25 powered 240 to the diner the other day to get some coffee with friends, When pulling out of the parking lot my motor changes over to a much rougher sound (Like a cylinder stopped firing right), So I quickly and carefully drive the 1 block to my house and park it, pretty pissed because i figure i just lost my motor. Upon a compression test i find the following-Cyl 1 120psiCyl 2 120psiCyl 3 90 psiCyl 4 110psiCyl 5 110psiCyl 6 120psi

I have oil in my Coolant, and fuel in my oil...

My initial guess was possibly a head gasket... But after the compression test im definately thinking piston rings... Any ideas, maybe some further test suggestions?

[240z4u]

Coolant and fuel in oil says headgasket or cracked head/block. Sorry dude. Were you beating on it in a way that may have caused damage?

Leakdown test!

Evan

[Cjmartz2k]

Didn't sound like he was beating on it, but if it overheated, that could have warped or cracked the head and taken out the head gasket.

OP--those are low compression figures across the board, but that doesn't really mean to much as long as they are the same. They aren't though. Pull the head and see what kind of mess you are in for. Sorry to hear about your bad luck.

[SullivanRacing06]

pull head n check h/g, fuel n coolant in the oil would be due to the h/g failing/ warped head from overheating.

sorry to hear that man

[DeformityX]

Those were my original thoughts... And ill be pulling the head today, maybe ill get some pics ;P And no i wasnt beating on it, however, it did have an overheating problem when i got it, from a hole in the radiator. Long since fixed though. But yes, i can see that being the culprit... Well, we're gonna find out in a few hours =) Thanks guys, ill keep ya updated.

[Cjmartz2k]

gambahtey

[DeformityX]

Hey Sorry its been so long guys. So we pulled the head apart and this is what we found...Intake cam was gauged and knicked up...2 Valves bent...#5 cylinder damaged from a valve strike...and the head itself was gauged and knicked up around the cam journals.And a bunch of metal shavings in the head. Oh the joys. I dont really know what else to say but "f*@#!"

What do we think fellas? Sounds like I somehow skipped a few teeth on my timing belt sending my cam timing down the drain or...???Either way... Coolwhip, Ill get in contact with you soon on aim.

Ps: Guess its "Welcome to the NRRBA" for me -.-
Modified by DeformityX at 9:01 PM 1/6/2010

[tight240]

Well you already found the problem..... i was going to suggest pooring oil down the cylinder with the least compression and compression check again. If the compression improved in the cylinder with the low compression then that means the rings are fried. i guess i will save it for another thread, i thought i was going to feel speacial with that advice

[DeformityX]

Well you already found the problem..... i was going to suggest pooring oil down the cylinder with the least compression and compression check again. If the compression improved in the cylinder with the low compression then that means the rings are fried. i guess i will save it for another thread, i thought i was going to feel speacial with that advice

Yeah I did the wet compression test right before i pulled the head... all cylinders only went up like 3 to 5 PSI, not too significant of a change. But yeah... my RB's down for a good while now... anyone wanna loan me about 1400 bucks? ;P haha jk

[240cp]

Did the timing belt break or something?????

[tight240]

Is your #5 piston f*(^@ too? If not why dont you just find someone parting there 25 out and buy a head from them? Or you can get a short block from coolwhip, and throw everything in there then you have a spare bottom end you can build up.

[DeformityX]

No timing belt actually looked perfect imo...

And Itd be cheaper to just get a long block from coolwhip, than to swap everything over as I'd need a new head, cams, pistons/rings and valves... and god knows what else...