rb25 swap fail, how does this even happen

[Terrh]

http://s170.photobucket.com/al...roken/

Got the RB25 in. Got it running. Drove around a bunch to make sure there were no problems. Everything was peachy until about 10 miles in when this happened.

Engine had plenty of oil, cam looks good still aside from that. Pretty sure valves got bent considering 2 of them are very open with the cam in that position.

this ever happen to anyone else?

Good thing I have a spare head.

[eh?]

Cam caps installed incorrectly could probably do that. I hope you replace the idler& tensioner/bolts&studs the next time around..

[krayton]

did u install the timing belt?

[mott6904]

Did you have oil pressure? What does the cam journals and camshaft look like. Did you have any top end noise while it was running?

[Bluefire]

remove the other cam, turn the motor over so that all the pistons are 3/4" of the way down. Now try and turn the broken cam over to see if it is seized

[Terrh]

timing belt was new, I installed it. It was tensioned properly. The cam caps were never off though to my knowledge.

I haven't pulled the cam yet so I dunno what the journals look like - I'm starting to think siezed cam as well. Top end was nice and quiet, no lifter noise or anything. Much quieter than the RB26 in my GTR. I love hydraulic lifters.

I can't say how much oil pressure there was since there isn't a gauge - but there was enough to put the warning light out. I verified as well (before it quit) that lots of oil was getting to the intake cam, looking through the oil cap.

[240slidekat]

how exactly did you tension it? and is that a stock cam?

[USMCgetsome]

i've seen this occur on this forum a few years back. Started as small metal shaving then fell off. The guy it happened to was not using the top timing cover. Then he installed the cas mount with cas. Then that happened.