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4JG2 Timing belt let go, now it's making more noise

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4JG2 Timing belt let go, now it's making more noise

Postby Yarno » Sat Aug 01, 2015 10:51 am

Hi Guys,

I have just replaced the timing belt in my 96 MU (4JG2) as the old one let go, this was whilst doing 100Km/h. Now when it let go the engine fluttered when it went out of timing, then there was a cloud of smoke (fuel I'm guessing), I then took my foot off the throttle and the MU went to idle (automatic transmission) then it stopped. There were no knocking noises or crunching sounds. We tried to start it but it just turned over really fast, no compression, I'm guessing the valves were all a little open.

So I have just taken my chances and changed the belt without checking anything else, I turned the engine over by hand and there was compression and noting that stood out being wrong. So I started it and it started first crank, and it Idles very well and smooth. But now it seems like it is making a louder resonating sound through the intake. Would anybody know what might cause this? I would have a guess that it could be bent push rods or maybe out of timing, but the timing is very simple with the lock bolts in place when putting belt on.

Any ideas??
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Re: 4JG2 Timing belt let go, now it's making more noise

Postby geeves » Sat Aug 01, 2015 3:36 pm

could be a bent valve /push rod but 1 tooth out on the cam will also cause this and the pistons end up very close to the valves
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 4JG2 Timing belt let go, now it's making more noise

Postby nb422 » Sat Aug 01, 2015 7:49 pm

Id go pushrods or valves, most likely pushrods.
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Re: 4JG2 Timing belt let go, now it's making more noise

Postby Yarno » Sun Aug 02, 2015 7:59 am

Ok so I have been thinking about it and I think it is the inlet valves. Bent pushrods only open the valve less, but what I have is leakage back into the intake. I did notice some hissing back through the turbo when I was turning it over by hand.
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