V-Belt Removal Questions

[PANDA]

96 3200 SCR - Twin 5.7 Mercruisers

I believe I have some belt squeal but would like to isolate from where. IIRC one of the motors has 4 v-belts (the one with PS) the other 3 v-belts? I am relatively new to working on boats and most of the maintenance has been done by the marina. I thought this would be rather simple like in a car. (move a tensioner pulley and remove belt) but it looks like the only way to remove the belts is to remove the pulleys, all of which look to be attached with like 6 bolts. Except the alternator v-belt I see a adjustment on that. But would still need to remove a pulley to get the belt off. Any info would be appreciated.

Thanks

[mmwjr]

Hi PANDA,
V belt don't have a belt tensioner you remove them by losening the alternator, power steering pump, raw water pump bolts that mount for mentioned to their brackets. They should have a slotted hole where one of the bolts is fastened which allows you to swing the alternator, etc. in to remove tension and then slip the belt over the pulleys. There is no need to remove the pullyes. When putting the belts back on you can use a long screw driver in place of the belt prybar to put tension on the alternator etc. and have to tighten the bolts while maintaining tension. A picture would help in pointing out things a littel better.

[ss3964spd]

I would also add that if you're using V belts you do not want to put too much tension on them. Too much tension may cause premature failure of bearings in the accessories that the belts run (Alt, PSP, etc). Basically you want just enough tension to eliminate any belt squeal. They make a special tension measuring tool but you can accomplish the same by a little trial and error.

Dan

[PANDA]

Originally Posted by mmwjr

Hi PANDA,
V belt don't have a belt tensioner you remove them by losening the alternator, power steering pump, raw water pump bolts that mount for mentioned to their brackets. They should have a slotted hole where one of the bolts is fastened which allows you to swing the alternator, etc. in to remove tension and then slip the belt over the pulleys. There is no need to remove the pullyes. When putting the belts back on you can use a long screw driver in place of the belt prybar to put tension on the alternator etc. and have to tighten the bolts while maintaining tension. A picture would help in pointing out things a littel better.

The thing I worry about is the tension or doing this wrong. Then I am stuck out on the lake with a blown belt.

Originally Posted by ss3964spd

I would also add that if you're using V belts you do not want to put too much tension on them. Too much tension may cause premature failure of bearings in the accessories that the belts run (Alt, PSP, etc). Basically you want just enough tension to eliminate any belt squeal. They make a special tension measuring tool but you can accomplish the same by a little trial and error.



Dan

So if I have a squealing belt I should try to loosen it and see if it gets better?

[mcoffey]

I have always found a bit of water was good for locating noisy belts. Just fill up a spray bottle or empty drinking water bottle with tap water.
Start the engine and while running, spray/poor a little bit of water on 1 belt (into the V groove though, not on the back side).
One of 3 things will happen, it will do nothing at all, it will get noisier or it will get quitter.
If nothing at all, move on to the next belt (only do 1 at a time).
If louder or quitter, that is your troublemaker.

Now you should repeat this with all belts in case more than 1 are making noise.

Once all are isolated, push the belt in on it's longest side between pulley's.
Compare that deflection to the others that are not making noise and then tighten to match.
I have seen in some cases where a replacement is needed to stop noise though most of the time tightening fixes it.
I have never had any luck with belt conditioner (spray on that is supposed to stop squeals). Most of the time it creates more issues than it fixes (more slipping and noise over time).

[mmwjr]

A squealing belt is the sound a loose belt makes and not from being to tight. It squeals because it is slipping. Yes I heard sraying a little water on it can help identify which belt it is.