tensioner replacement

I need to replace my accessory belt tensioner, the one that drives the alternator. It's noisy. I figured I would replace the assembly, seems easier than removing the pulley. Anyone have a part number for a tensioner assembly for heavy-duty cooling LT1? I keep seeing assemblies for NON-heavyduty applications, I have yet to see one listed as specifically FOR heavy-duty. Thanks...

I don't know a part number Doug, but those are an over the counter part at any parts store. At least they were, as I have bought them there.

Tom

Bought one at autozone about a month ago, it was under $40. If you don't have a mechanical fan its a 10 minute install and you don't even need to go under the car.

Thanks Tom, David- I guess I will take my chances at the parts house.
Since I do have the mechanical fan, are there any gotchas to replacing the tensioner?

Nothing much, just have to work from under the car. I don't remember having to remove anything extra when I did this in my tow pack wagon.

Easy job to do on a LT1 - as David Points out can be done under the car. Remove the Belt, and there is 2 bolts to remove. Install is just as easy.

The main serpentine tensioner is the same between the regular and heavy duty. The mechanical fan has an additional smaller tensioner.

It's kind of a pita with the mechanical fan, as I think you need to take the fan and bracket off to get the belt off, but still less than an hour to do.

Thanks gang. Nice to have support as I keep this 217,000 mile vehicle on the road.

A bit of followup on tensioners:

Tensioner #1, serpentine: Easy to find over-the-counter. Easy to replace on a HD cooling LT1 from the bottom. Just have to take tensioner #2 off first. Mechanical fan/bracket did not have to come off for me.

Tensioner #2, fan belt: Couldn't get the assembly or the pulley at the O'Reilly's, Advance, or CarQuest counters. The pulley is plastic so pressing a new bearing in doesn't seem feasible. There is a number cast on the assembly(10186118) which matches a search at gmpartsdirect, looks to be a GM part number. They want 50 bucks plus shipping. This is what the tensioner looks like:
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I replaced tensioner #1, noise seems better but we'll see what happens. I hope it isn't the water pump. Neither of the tensioners make a lot of noise when I spin them under zero load.

alternators get noisy too , take a 3/8ths long extension and use it as a listening post,.


Nick

Its old school and doesnt require a battery either,but it works.
Jim

I bought a new one of the fan tensioners years ago when I first got my Roadmaster. Its still sitting in my cabinet of parts and I never used it. I remember it being extremely expensive and a GM only part.

nowhereman wrote:

...I replaced tensioner #1, noise seems better but we'll see what happens...

It could be the compressor bearing.
See if the noise goes away when you engage the AC clutch.