New Timing Belt Destroyed And New Oil Leak

[datsun_1600]

Hey - it was a sad day in the shed today... I changed the timing belt and tensioners on my R32 GTR and now I have some serious problems....

I would consider myself fairly experienced in the shed, i've built say 10 high performance L series Datto engines and have tinkered in the shed since I could walk. Changed quite a few timing belts over the years with no issues.

OK so this is how it went down:

1.) Pulled the old timing belt and tensioners off

2.) replaced the tensioners

3.) Fitted the belt (100% sure timing was ok - and it still is ok)

4.) Adjusted belt tension as per the book. Timing belt flex was basically the same as the old one.

5.) Tuned it over a few times by hand - tension all ok.

5.) Refitted everything required to run except upper cam pulley cover

6.) Fitted the CAS without the cover and started the engine - all ok.

7.) Ran it for a few mins and observed the belt - ran true and was all ok

8.) Fitted the covers etc etc etc

9.) Started it and it and after about 10 seconds it made a strange sound - like the a flange rubbing on the front pully or something.

10.) Killed it immediately (was standing at the engine so I guess it ran for a few seconds)

I stood there for a good ten mins thinking about what it could have been... anyhoo... I then noticed oil leaking from under the front pulley... I pulled the top cam cover off and noted that the new belt had partly disintegrated and there was oil everywhere.

I haven't pulled the bottom cover off yet so I don't know if if the oil is coming from the front main or the cam towers or what.

Has anyone got any ideas as to what might have gone wrong ? New tensioners look ok but can't tell if they are stuffed until I pull the radiator bottom covers etc etc. It almost looks like the belt was rubbing on something - the edge facing towards the engine...Then it shredded and the long sting bits wedged up hard again the oil seals and took them out...

Any ideas ? I'll grab a new belt / seals tomorrow - but I just don't want this to happen again... Thank god the belt didn't break.

Cheers,

Jeff

[RB25 SKYLINE]

what brand of belt and tensioner?did u buy a full kit including seals?did u replace all seals?id be pulling both covers off and check for rubbing on the covers or anywhere else.also check all pulleys for any movement.one thing ive learnt over the years is do skimp on a timing belt kit.hope this helps good luck.

[datsun_1600]

Cheers mate will do - everything is genuine Nissan stuff. Didn't replace the front main or cam seals as they were done about 30K ago... but i'll be doing them now I guess.....oh well live and learn - i'll post back with what caused it when I pull the bottom cover off tomorrow....

[datsun_1600]

I should add - seals were done just before I got the car - wasn't sure if the belt was done or not - so I decided to change it.

[datsun_1600]

Update - Pulled the bottom cover off. The only thing I could see was they idler puller tensioner spring was not sitting on the locating dowel. But it was correct when it was installed so i'm guessing the belt strands dislodged it... The belt strands also look like they have wrapped around the cams and crank taking out the oil seals... Wish I could see what the inner side of the belt rubbed on....

[datsun_1600]

Another update - I think I have worked out what went wrong. I just inspected the idler tensioner pulley. To my great surprise I found it totally stuffed. Brand new Nissan OEM part. I am guessing as it has so much free play it caused the belt to not run true, which pushed the belt into into the spring, which took a few good chunks out.... New one coming in tomorrow...