Alternator V-Belts rattling. Should I replace?

[TOBASH]

Alternator V-belts rattling. Don’t appear to be a matched set, although that’s what I ordered when I bought them.

I tensioned them warm with a three foot breaker bar.

I will try to post a video later to see if the video looks normal or if you guys think I need to replace the belts. Note the wear pattern. I think they are hitting each other.

(I wish there was an easy way to post iPhone videos)

EDIT - I have added a YouTube link after post # 5 was made.

 

[MarkM]

You don't want to put too much tension on the belts as it beats up the bearings. Rule of thumb for me is about 1 1/2ft span you want around 1/2" or there about defection and they have tools for this unless your used to doing it with your fingers. Do each belt have about the same defection/Tension? A video of the belts in use will tell you if your about right

MARK

 

[TOBASH]

You don't want to put too much tension on the belts as it beats up the bearings. Rule of thumb for me is about 1 1/2ft span you want around 1/2" or there about defection and they have tools for this unless your used to doing it with your fingers. Do each belt have about the same defection/Tension? A video of the belts in use will tell you if your about right

MARK

I purchased “matched belts” and they are not matched.

One belt is certainly less tight by touch.

I guess I’ll by another set and keep these for an emergency

 

[juanprado]

To determine if you have a matched set. Look at the mfg code of the production normally after the part numbers. For example gates will have numbers/letters. I have seen some brands having the same numbers others having sequential that tells you the 2 pieces were cut side by side from the same chord.

Gates will have a piece of red tape around a set. Napa is gates btw.

 

[INFChief]

To determine if you have a matched set. Look at the mfg code of the production normally after the part numbers. For example gates will have numbers/letters. I have seen some brands having the same numbers others having sequential that tells you the 2 pieces were cut side by side from the same chord.

Gates will have a piece of red tape around a set. Napa is gates btw.

What do the belts turn? Check to make sure whatever they turn (alt / gen, water pump, PS pump) that the device is properly mounted and the outer pulley isn’t pointed inboard or outboard a bit. If the alt / gen (whatever) isn’t square or true then one belt will be tighter than another.

 

[TOBASH]

YouTube link

 

[INFChief]

YouTube link

That doesn’t look bad to me. Belts will deflect when under tension & they don’t deflect in unison. There’s a few ways to check belt tension - which will tell if one belt is looser than the other.

1) A belt tension tool
2) Straight edge and ruler.
3) String & ruler or tension gauge.

Essentially you will depress one belt in the center of the belt between the pulleys. The straight edge will be held on the top across both pulleys and the bottom edge will be where you measure downward deflection from. Measure the downward deflection and write it down - or remember it. Repeat for the other belt. Compare measurements. You can Google or search YouTube or even refer to the appropriate TM for the correct process.

You should be able to find the recommended deflection in the TM as well.

 

[papakb]

If the wobble settles out when the engine speed increases your good to go. As for matched sets if you have a good shop nearby (more than a kid with pimples and a catalog) that will let you look thru their belts look for 2 from the same manufacturer AND look for a couple with matching production date codes on them. This could mean they came from the same batch and have a good chance of being the same size. Different date codes mean different batches and it'll be anybodies guess as to haw closely matched they are.

 

[simp5782]

They make double V belts made together that gets rid of the one getting loose before the other

 

[TOBASH]

They make double V belts made together that gets rid of the one getting loose before the other

Where would I search for a double V-belt. I’ve seen a lot but I’ve never seen these

 

[AAVP7]

Is it just me, but it looks like the rear of that 60A alternator is moving a lot ? More than mine, anyway.

 

[Mogman]

That gen does look like it is moving a little too much, other than that the belts look pretty much "normal"
The span from the gen to water pump is too long for a v-belt installation, no matter how tight it is going to look like this.
AFIK nobody makes "matched" sets of belts anymore, best you can do is match production codes.
I am certainly not going to miss the v belts, as the new engine going in the Detroit has a serpentine belt...

 

[simp5782]

Where would I search for a double V-belt. I’ve seen a lot but I’ve never seen these

They are on the gates site.

Just email their tech support with the current belt #s and they will tell you which one. Otherwise you gotta find the belt by all the different measurements

APAteam@gates.com

 

[Retiredwarhorses]

YouTube link

there is no issue here…v-belts regardless of matched set or not will bounce around at idle.

 

[TOBASH]

Thank you Steve

 

[Coug]

Might want to make sure the rear bracket for the generator that goes to the exhaust stud hasn't sheared off the exhaust stud that it goes to. Mine looked like it was all there and in place, but the stud the bracket goes on sheared off at the block so the nut for the exhaust manifold and the one for the bracket held it in place unless you looked closely. (200 amp system for mine, but I think the bracket goes to the same place)