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TR2/3/3A Overtightening the alternator belt?

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K

karls59tr

Obi Wan
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The belt seemed to loosen fairly often so I tightened it good. Now I can hear the death rattle of a broken chain tensioner? It's a major job to get at the tensioner and I may as well replace the chain and sprockets while I'm in there. Is it possible that overtightening the belt would put pressure on the on the pulley and sprocket somehow or was the chain tensioner ready to fail anyway?
 
I would say there is no relationship between the fan belt tightness and the timing chain tensioner. I would better guess that you are hearing a lot of noise from the water pump or pulley that you might think is coming from the timing chain area. And both of those are suspect at failing if you over tightened the fan belt.
Charley
 
karls59tr said:
... Is it possible that overtightening the belt would put pressure on the on the pulley and sprocket somehow ...
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Not really.

Generator/alternator and water-pump bearings do not like an overtight belt, but it won't affect the chain tensioner.
 
To clarify post 3, and as Steve said, it would only be the water pump and generator that would be harmed by an overtight belt. It has absolutely nothing to do with internal engine components.
Bob
 
Well it seems I have a mystery rattling noisy coming from the engine. Last thing I did was tighten the belt so I thought it might be related. The noise sounds like a chain rattling....mostly at low revs at idle...seems to quiet down at higher revs? I put the stethoscope on the timing chain cover but did not hear the sound? Cant think of what else could be vibrating like that?
 
karls59tr said:
Well it seems I have a mystery rattling noisy coming from the engine. Last thing I did was tighten the belt so I thought it might be related. The noise sounds like a chain rattling....mostly at low revs at idle...seems to quiet down at higher revs? I put the stethoscope on the timing chain cover but did not hear the sound? Cant think of what else could be vibrating like that?
Click to expand...
I would submit that you are believing that the noise you are hearing is something and you are limiting your search. Besides the two items I previously listed I would add the generator / alternator.
Charley
 
You can remove or slacken the belt entirely and run the engine long enough to see if you still hear the noise.

If you do then that eliminates the water pump and generator as a source.

If the noise goes away you can fashion a belt from a rope that only goes from the crank to the water pump to determine whether the pump or the generator was the source.
 
Listen to the gen and w pump with stethoscope. Not too many other things rotating while engine is running. If you can't isolate it, back off belt a bit and noise should go away
 
NutmegCT said:
Karl - what was the cause of the rattling/clunking noise in the rear of the car?
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The rear bracket that holds the body to the frame had had failed because of rust where it bolts to the inside of the spare tire compartment and the bottom plate where the bracket bolts to the frame was broken. (Did not do a body off resto on this car). I fabricated an "L" shaped bracket to hold the bracket to the frame and made a backing for the bolts inside the tire compartment. Have not done a test drive yet to see if I resolved the problem.
 
I still have the wide belt but you make a good point about the worn woodruff key. That actually did happen to me years ago and it does make a rattling sound. Had forgotten about that till you mentioned it. This time the problem was different. Turns out it was loose bolts where the front cowl bolts to the support bar on the bonnet that allowed that part of the hood to vibrate!
 
Thanks to all who replied. đź‘Ť Turns out it was nothing major. The two bolts that fasten the driver's side of the front cowl to the support rod had worked loose causing the cowl and bolts to have a sympathetic vibration with the motor revs of all things! Here I was ready to replace the the timing chain tensioner thinking that it had failed. Doh! :rolleyes:. The stethoscope came in very handy in tracking down the problem. I also backed off the tension on the alternator belt as I had it tighter than necessary. Karl
 
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