I don’t want to jinks this by saying that I’ve finally solved the problem. I’ve learned from several previous attempts to solve the chirp, only to be welcomed by the Chirp-Chirp-Chirp several hundred miles down the road.
To date, everything I’ve done to resolve this had a temporary effect, but then it comes back. The pulleys have been cleaned, wire brushed, parts replaced, belt/pulley alignment checked, etc, etc, etc. This is a short list of what I’ve done.
1) Replace three idler pulley bearings, replaced with Gates belt (81102)
2) Replace Gates belt with OEM Motorcraft belt.
3) Replace tensioner.
4) Replace two idler pulleys.
5) Replace OEM belt with shorter belt to increase tension (81088)
6) Replace water pump, machine water pump drive wheel to repair smooth surface.
TROUBLESHOOTING
In one of my troubleshooting exercises, I put a wrench on the tensioner and pulled it a tiny bit tighter, and the chirp would go away, This is the reason I changed the tensioner (no help) and also tried a shorter belt (no help)
One of the latest troubleshooting steps, was to use a small spray bottle of water. I had a long nozzle on it so I could safely reach up near the pulleys while the engine was running. I would give a short squirt of water to the belt surface just before it engaged a pulley.
The chirp would consistently go away when I squirted the belt just as it engaged the water pump pulley, This is the reason I pulled the water pump and machined the pulley to ensure it was flat and aligned with the belt. Again – no help)
LATEST ATTEMPT
This is my latest attempt – I read on the Ford Enthusiast forums that several others were also chasing the elusive chirp (many had given up and just live with it). They seemed to stumble on a drive belt made by Continental. This belt has cross groves in the belt that are at an angle with the normal drive groves.
The theory was, the additional groves allow the belt to flex a very small amount, thus preventing the skidding of the belt on the pulley (which causes the chirp)
We went on a short trip last weekend and no chirping. HOWEVER, I remind myself that the proof will come in a couple months when we hit the road for our annual 6000 mile cross country road trip.
Hopefully, I won’t need to pack my bottle of aspirin to get rid of the headache cased by Chirp-Chirp-Chirp..
NOTE – I’m happy to report, this will be the final installment in the “Chirp-Chirp-Chirp” sequel. We just completed a 7,500 mile winter trip across the U.S. and there wasn’t any sign of chirping for the two months we were on the road.. YYYYYEEEEEESSSSSSS …..
Good Luck! I hope the new belt gets rid of the crickets for good!
Tom, tnks. I hope so…
Having been a truck mechanic too many years. I come across this many times. If you can’t replace the belt w/ new try spinning the belt backwards. It may be that the belt has been slipping or acquired some debris from rusty pulleys.
Good idea