2001 Mirada serpentine belt - Chirp-Chirp-Chirp

[waiter21]

I've been fighting this since I purchased the Mirada used several years ago.

To date, the idlers have been replaced, the belt has been replaced, and the tensioner has been replaced. This all seems to work for 50-100 miles, then its Chirp-Chirp-Chirp again.

My latest attempt is to install the shortest belt I could get on it, I tried a 108 1/2, but I couldn't get it on. I was able to get a 109 3/8 belt on, but had to remove then re-install the idlers, not a big deal.

I'll need to drive it a few hundred miles to see if this stops the chirp.

Chirp-Chirp-Chirp – Try a smaller belt | 2001 Coachmen Mirada 300QB

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[Kenny kustom]

I had a heck of a time with a crate engine once.
The only thing that did it...
I found a good year gator back belt.
That's after using every gates and day I belt on the shelf.


2016 Sabre 36QBOK
2015 Ram 3500 CUMMINS

[KAttkisson]

If you have to address this again in the future be sure to inspect the grooves in the crank pulley. They can be damaged by debris. A new belt will cover this up until it is run in and "damaged" by the deformed pulley.

[waiter21]

Thanks for the heads up on the grooves.

The crankshaft, AC, power steering, and Alternator are grooved. If the problem comes back, the next step is to carefully measure groove alignment. Unfortunately, things are tight on the front of the engine and I'll probably need to remove the fan blades.

I've been reading through the Ford forums, the high probability for groove misalignment is the power steering pump.

We're doing a west coast run later this month (5,000 miles) so I'll be able to tell if the smaller belt helped.

[wahoonc]

Groove alignment is likely the primary cause. You might be able to get away with using some belt dressing on the belt to reduce the noise. However it will come back. Sometimes new and improved... ain't. But then again some of the old engines I have had in the past had multiple belts and it was always the one in the back that broke.

Aaron

[KAttkisson]

Just something to think about. The engine idles at about 750rpm. The fan pulley turns about the same speed with other accessories turning at higher speeds. If you are able to make out individual chirping sounds there is a bad place in the belt--not the pulley. all pulleys involved are turning too fast. They would produce what to the ear would be a constant noise.

What causes a burnt place in the belt? I once had an AC compressor that was getting liquid into it and would instantaneously lock up when trying to start. There are other causes. Alignment could set up a situation where the belt is not fully seating across its width which in a start-up situation with the AC could put a burn on the belt. Mis-alignment itself will probably not cause an intermittent noise.