1G Auto Tensioner

[Paturk]

I have redone the timing on my 1st dsm for the first time and I drove a little and now the belt is tighter when I first out it on and the pin in the auto tensioner is pushed all the way down. Is this supposed to happen on these cars? It’s giving my a decently noticeable whine and wobble from the cams.

 

[Spleen8urLSX]

Not at all supposed to happen, and that whine is likely strain on your oil pump so definitely don’t keep driving it like that for several reasons. I would pull the cover back off and assure the tensioner pulley itself is in the proper position and didn’t move. Without looking at it it I’d have to guess the tensioner pulley somehow slipped adding tension, the tensioner pulley wasn’t installed correctly, or the auto tensioner is bad (though when the auto tensioner is bad it’s usually opposite effect). Did you replace the auto tensioner with a new OEM one when you did the timing job?

EDIT: Misread that, thought you said the tensioner pin was all the way up, not down, but yes something is no good or not in the least bit correct as listed above.

 

[Paturk]

Not at all supposed to happen, and that whine is likely strain on your oil pump so definitely don’t keep driving it like that for several reasons. I would pull the cover back off and assure the tensioner pulley itself is in the proper position and didn’t move. Without looking at it it I’d have to guess the tensioner pulley somehow slipped adding tension, the tensioner pulley wasn’t installed correctly, or the auto tensioner is bad (though when the auto tensioner is bad it’s usually opposite effect). Did you replace the auto tensioner with a new OEM one when you did the timing job?

I replaced the auto tensioner and it was fine at idle. I drove it and was fixing the idle issues I had, boost leaks, ips, etc. and noticed the belt was tighter than before and noisy. I checked the tensioner and the pin was all the way in, and when I looses the tensioner pulley to relieve tension the pin still hasn’t gone back up. The new one was supposed to be Mitsubishi from stm.

 

[Spleen8urLSX]

Unfortunately it sounds like the auto tensioner failed right out of the box. While I’m sure it was OEM (unless it came in non oem packaging) you have to figure it’s still a hydraulic part that’s sat packaged on a shelf for several years as whoever Mitsubishi had manufacture them hasn’t manufactured them in several years.

To some here this may be blasphemy but I’ve always had luck with the Gates auto tensioners, on my own car and several other dsm’s in the area. The body casting and overall design appears the same as the OEM, while brands like Dayco (known to fail prematurely, personally seen it several times) are smooth casting and some obvious differences from what Mitsubishi used. Take that for what it it is, but whether it was install error that damaged it or faulty out of the box if the hydraulic pin on the tensioner is stuck all the way down then we know for certain it’s no good.

Another thing to consider, that whining you describe sounds consistent with a failing oil pump. On more than one occasion I’ve seen excessive timing belt tension damage the oil pump from putting too much stress on the gears. If you re do the timing to spec and it proceeds to whine then don’t keep running it as you’ll be looking at replacing the front case, which might sound like it sucks but good you caught it now before catastrophic damage occured if that is the case.

 

[Paturk]

Unfortunately it sounds like the auto tensioner failed right out of the box. While I’m sure it was OEM (unless it came in non oem packaging) you have to figure it’s still a hydraulic part that’s sat packaged on a shelf for several years as whoever Mitsubishi had manufacture them hasn’t manufactured them in several years.

To some here this may be blasphemy but I’ve always had luck with the Gates auto tensioners, on my own car and several other dsm’s in the area. The body casting and overall design appears the same as the OEM, while brands like Dayco (known to fail prematurely, personally seen it several times) are smooth casting and some obvious differences from what Mitsubishi used. Take that for what it it is, but whether it was install error that damaged it or faulty out of the box if the hydraulic pin on the tensioner is stuck all the way down then we know for certain it’s no good.

Another thing to consider, that whining you describe sounds consistent with a failing oil pump. On more than one occasion I’ve seen excessive timing belt tension damage the oil pump from putting too much stress on the gears. If you re do the timing to spec and it proceeds to whine then don’t keep running it as you’ll be looking at replacing the front case, which might sound like it sucks but good you caught it now before catastrophic damage occured if that is the case.

Thanks I appreciate it. It sounds more like the whining is coming from the cam gear itself rather than the oil pump. It seems like the belt was over tightened and it even showed some visible wobble to them, but I will keep the oil pump in mind when redoing the tension