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I changed a timing belt on an RB25DET for a family member and unknown to me, a spacer or collar (what ever it was) found it's way where it didn't belong :D .

This caused the inlet cam to become retarded by 2 teeth and the exhaust cam to advance 2 teeth.

Resetting the cam timing and the engine to runs like a bought 1 (it wouldn't start befor).

The obvious question is, was there any potential to have damaged valves/pistons?

My main concern is that the boost gauge is showing about 11" mercury when idling. This seems low to me but I never paid any attention to the gauge pre busted cam timing.........

Other than that, engine is smooth as silk with a rock solid idle speed.

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i would say no... several teeth out wouldnt be enough to do any major damage, trust me you'd hear the valves touching the pistons when you first crank it over :D

Cheers. Like I said it's only the low idle vacuum that bothers me, but that could be a dud gauge or crap hose.

Cant really comment on the 2 teeth you picked up but ide say if the changes were made from TDC then you should be ok (considering how much *safe* adjustment you can get out of adjustable gears)

What exactly did you do to cause the problem? I only ask because I have a 25 and a 20 here both awaiting a new belt so I dont want to make the same mistake

Cant really comment on the 2 teeth you picked up but ide say if the changes were made from TDC then you should be ok (considering how much *safe* adjustment you can get out of adjustable gears)

What exactly did you do to cause the problem? I only ask because I have a 25 and a 20 here both awaiting a new belt so I dont want to make the same mistake

Somehow a steel spacer that I can only guess was from the timing belt cover got in behind the timing cover. I found it sitting between the cover and the tensioner roller. I think we (I) were very lucky, and propably the only thing that prevented major engine damage was because the owner was (suppose to be :rofl: ) taking it easy due to a dud fuel pump.

Belt replacement is quite straight forward, just leave out any and all small and large belt wrecking items and it will all be sweet :D

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