1983 ford e350 with 460 in motohome. has the dual v belt power steering system. just replaced both belts now they squeel when i rev? any ideas? pump going bad?

 

How long has it been since they were brand new? New belts sometimes need readjusting soon after installation. And, did you get a matched belt set?

 

i put them on yesterday was about 4 hours from home when one broke so replaced both with gates 7550's and the squeel gets loud if it goes over im guessing 2,500 or over 55 mph. I also pulled over again to check make sure they were tight. only thing i noticed was the grooves in the new belt were spaced differently. the old belts were 25-7550 napa part numbers

 

According to this site those cross-reference properly to each other. And, if you click on the link for them (15550) you'll see that it is a 15/32" x 55" belt. And, the Ford catalog shows that's what your vehicle takes - although it says the belt should be slightly longer. But that won't make them squeal. So, you have the right belts according to the catalog.

But, that doesn't fix the squeal. Perhaps there is something wrong with your power steering causing it to take a huge amount of power? If not, then maybe your pulleys have been polished and that is causing slippage. My dad used to take a round file and lay it in the pulley and hit it with a wooden or rubber mallet to put a bit of tooth in the pulleys when one was squealing - and that fixed it. Other than that, I don't know.

 

I friend uses WD40 on squealing belts. I've never done it because I wonder about the long term effects. Just passing the tip along, not recommending it. I think it might soften any glaze on the belts. Or, maybe just lubes the slipping belt so its quiet.

 

LOL! That's an interesting approach - fix the squeal and not the slippage. But, maybe it really does fix the slippage? Dunno.

 

Odds are you ended up with belts from 2 different batches and they are slightly different legnths.
I finally gave up trying to get a pair that matched and would run quietly and put one behind the seat of my truck, never had a squeal going down the road but lots of noise at idle. Going to a single belt has not been an issue, the double belt system was only on a/c 460's and non a/c diesels.
Try running just one belt and see if it fixes your noise, if not something is causing the pump to drag.

 

Ah yes, 460 belt squeal at 2500+ RPM. Mine was caused by the fan clutch locking up (overly stiff really) and not releasing.

Does the fan seem unusually loud now, especially at higher RPM? I wonder if it was extra drag from the fan that caused your old belt to fail?

At normal temperature (with the motor shut down of course) the fan clutch should allow the fan to spin fairly easy. Perhaps a full revolution with a moderate fling.

On the other hand, if you're running hot the fan clutch is supposed to tighten up at lower RPM (like in traffic) in order to move more air...

Anyway, they're big fans and they will squeal at 2500+ RPM if the fan clutch isn't releasing at higher RPM like it should.

 

ok thanks for the tips guys im going to check the fan when i get home and also get rid of one of the belts. I thought about doing it already i too didnt see a reason for 2 belts serving the same purpose

 

That's why I asked about the matched pair. The vendors actually sold, at one time, matched pairs. Just buying two of the same thing doesn't mean they are matched.

 

IMO you really need both belts to drive that big ole fan.

 

Ford only thought you needed the second belt if you got A/C on a 460, or didn't get it on a 6.9, and it's fan is a good bit larger than a 460's, never had an issue with either my 460 running a single belt, or my 6.9 which only ever had one..

 

My truck didn't come with AC and it has two belts.???

I used to be able to buy matched pairs of belts.
A visit to the Gates website says that due to better process and QC this is no longer necessary.

Try cleaning the glaze off the sheaves with some emery cloth.
While you have the belts off see if the fan clutch or water pump bushing is starting to go.
Spin and wiggle all the pulleys by hand.

 

May be an 87 thing, I have an 86 non a/c parts truck that is factory single belt. I really wish I had my shop manuals here at the new house.
I have never actually seen a 460 powered 87, but I have seen a 351W one, and it was a bit different under the hood than an 86 even though it was still a carbed engine.

 

Hmmm

My '87 engine looks pretty much the same as my next door neighbors '86 F350 dump.
Except for the things I have changed, like the 3G and Saginaw.