Problem with drive belt. Need Help!
 

I am at complete loss. Can someone tell me what I did wrong!!

This is my before and after pics. This is a complete STOCK rebuild. Most of this was taken apart cleaned and repainted. These are the exact same accessory parts including PS pump, alternator, all pulleys and belt.

My problem is when I put it all back together the belt will not go back on. I do not know what the problem is. (hopefully all the pictures will load properly)

Re: Problem with drive belt. Need Help!
 

Not sure why my they are sideways but here is where im at...

Re: Problem with drive belt. Need Help!
 

...

Re: Problem with drive belt. Need Help!
 

Thats the same belt I took off when I bought the engine.

Re: Problem with drive belt. Need Help!
 

Are You saying it's to long or to short?...the way your holding it makes me assume you think it's short..(blue arrow)... Did you put a wrench on the tensioner..?.(yellow arrow)

Re: Problem with drive belt. Need Help!
 

Well at first glance whats up with your idler pully????? That looks to be the wrong pully by looking at the bearling guard

Re: Problem with drive belt. Need Help!
 

Attached what stock idler looks like

Re: Problem with drive belt. Need Help!
 

His looks like mine dude...

Re: Problem with drive belt. Need Help!
 

Too short. My left hand is holding the tensioner all the way down and thats as far as I can pull the belt

Re: Problem with drive belt. Need Help!
 

These are the exact same parts I took off the truck. I can't figure it out. My next move will be to take it all apart and start over!

Re: Problem with drive belt. Need Help!
 

Yeah mine is exactly like that. The first pic was to show my belt routing and the second was to show how far I can get it. Thats a ratchet in my hand in the other pic.

Re: Problem with drive belt. Need Help!
 

I'm in the shop trying to replicate what your seeing...
1st pic is tensioner relaxed
2nd pic is tensioner all the way over
3rd pic is with belt on...
I did get the same result your seeing when the belt was not down in the power steering pump pulley good...it was sitting up out of the groove..

Re: Problem with drive belt. Need Help!
 

Here's a pic with the belt partially out of the groove on power steering pump...looks just like what your seeing...

Re: Problem with drive belt. Need Help!
 

Yes. My belt orientation, tensioner pulled, as far as I can pull it.

That may be the problem. Ill get the wife in the garage this evening and see of another set of hands will help. I first thought the power steering pump wasn't correct but it looks fine. My only other thought is to take it back a part and try again.

Re: Problem with drive belt. Need Help!
 

Your "before" picture doesn't have an alternator on it, so are you positive that is the alternator that goes with that belt? Because there are two different belt sizes depending on which alternator you have. The shorter belt works with the smaller alternator and the longer one works with the bigger one. You have the big alternator in your "after" pics. So, unless you don't have the belt all the way in the grooves of the pullies, then you have to have the wrong belt for your alternator.

Re: Problem with drive belt. Need Help!
 

All parts are the ones that came off the engine when I got it from the junk yard. Belt and alternator. This is my first complete rebuild but I'm not a complete rookie in the garage. I have no idea what the problem is. I hope I'm slipping out the grooves and can't tell, Im gonna get some extra hands tonight and see if that works. If not I guess ill take some stuff off and try again. I put a rebuild kit in the PS pump but everything bolted right back into place.

Re: Problem with drive belt. Need Help!
 

I am having the exact same problem! I thought I was going crazy! All original parts except the water pump. I will double check that the belt is fully seated in the grooves. Let us know if you figure out what the problem is!

Re: Problem with drive belt. Need Help!
 

Took the alternator off used a rubber mallet to tap it down and got the belt on. use the same mallet to tap the alt bolts in and it raised it back up. I was able to take the belt off again but had the same problems trying to put it back on. Not happy because this is obviously not the way this system is designed but nevertheless the belt is on! Still not sure what the problem is but can move on to finishing my project.

Re: Problem with drive belt. Need Help!
 

That's very strange that it wouldn't work as designed....

Re: Problem with drive belt. Need Help!
 

Agreed. Hopefully I can get this truck running by the end of the month and can research this a little further.

Re: Problem with drive belt. Need Help!
 

If I were a betting man, I'd say you have the wrong belt. Like I said earlier, there are two different size alternators and therefore two different size belts. Somewhere along the line in the donor trucks 17 plus year history, someone got the wrong one and forced it on, it can be done. The fact that you took it back off and couldn't get it back on again tells me you probably just didn't notice the tensioner maxed out when you tore the engine down, as it likely came right off. There is no way I know of to put the accessories on wrong so that the belt is only an inch or so short. Just get a new belt for the big alternator and you should be golden.

Re: Problem with drive belt. Need Help!
 

Heres the belt thats on mine..

Re: Problem with drive belt. Need Help!
 

Could it be that the junkyard did the same thing, just shoved an alternator on there and made it work to get it out the door? And the belt was wrong all along? I have found them to do that all the time, every engine I get seems to have mismatched parts.

I am digging up a pic of my LQ4, and my alternator pulley seems a little smaller than the one in your pic. I can see the casting behind the pulley in my pic.

Re: Problem with drive belt. Need Help!
 

Could be but thats the belt that came off the engine and who knows what the previous owner did.... the only new part is those pics is the thermostat housing. You are right I do not remember the tension when I took it off. Its possible anything was put on there before I picked up. How do I identify the different alternators in order to get the other belt?

Re: Problem with drive belt. Need Help!
 

What alternator goes with that one?

Re: Problem with drive belt. Need Help!
 

I went to advanced auto and got the small belt went home and it was to small so went back and got the larger belt and it felt perfect.

Re: Problem with drive belt. Need Help!
 

It's the smaller one. He posted a pic of it in post #8, notice how much smaller it is than yours.

Re: Problem with drive belt. Need Help!
 

Thanks. I may end up having to do that!

Re: Problem with drive belt. Need Help!
 

Ok I see what your saying. Do you know if changing alternators would be a direct fit? Meaning same plug for the wiring harness? Same dimensions to fit in the bracket?

Re: Problem with drive belt. Need Help!
 

You mind sharing some info on your alternator? Brand, PN that sort of thing.

Thanks

Re: Problem with drive belt. Need Help!
 

Forcing the belt on like you did means it's the wrong belt period. You are guaranteed to prematirealy wear out some bearings. Just take that belt off and go to the parts store and ask for 3 belts, each 1/2 longer... return the ones you don't use... simple.

Re: Problem with drive belt. Need Help!
 

Jstock...mine is a 105amp....
The numbers on it are...15755616W. 105A 111623 12V N

But I wouldn't change anything but the belt...if that's the jssue

Re: Problem with drive belt. Need Help!
 

Will do. Thanks again for your help!!

Re: Problem with drive belt. Need Help!
 

Did you get this issue resolved?

Re: Problem with drive belt. Need Help!
 

Yes and no. I got the belt on by unbolting the alternator and tapping it down some and bolting it back down. Was then able to take the belt off but again could not get it back on. I still do not know the cause of this issue because I reused all the original parts from the teardown. Another member recommended buy several drive belts of different lengths, finding the one I need, and returning the rest. That is probably what I will end up doing.

Re: Problem with drive belt. Need Help!
 

Thanks for the reply, I wanted to check because I am having the same problem as you. Original components, original belt. The only difference was a replacement water pump but the "pulley", (for lack of a better word), was the same size. Suddenly. The belt no longer fits. This can't be coincidence.

Re: Problem with drive belt. Need Help!
 

I have no explanation! I took the parts off clean and painted and put them back on had problems. I put new gaskets and seals on the water pump and power steering pump. Im gonna go the route of trying a couple different belts until I get the right one instead of swapping alternators. Good luck with yours!

Re: Problem with drive belt. Need Help!
 

Been there done that. When i changed from the 105 amp alternator with an oem stock belt to the optional 140 amp larger diameter alternator i used i believe a 1" longer belt to make it right. I went to the parts store with the old stock one, measured, looked up the application and got the longer optional one and no issue, it is perfect. This is on a 2003 5.3

Re: Problem with drive belt. Need Help!
 

im being serious you have the wrong idler pulley on there , i work on these things every day i bet if you got this pully im linking from advance you woul not have a problem getting the belt on

https://shop.advanceautoparts.com/p/...67a/10150983-P

Re: Problem with drive belt. Need Help!
 

Look at the pulley gaurds first pic is yours there is a big gap between the gaurd and pulley second pic shows the proper pulley with no gap