Loud Engine Noise

[av42]

When pulling our La Palma W24 into a camp site this weekend, I shut off dash air while parking. Immediately a loud noise started it appears from the engine compartment. The noise (whine/howl)stops as soon as I turn the ac on and does not return until the ac is shut off. I have tried to pin point the noise but have not had much luck. It would seem like if one of the ac components is failing, the noise would be there with ac on, not off. Does anyone have any idea of what or where to look?

[av42]

When pulling our La Palma W24 into a camp site this weekend, I shut off dash air while parking. Immediately a loud noise started it appears from the engine compartment. The noise (whine/howl)stops as soon as I turn the ac on and does not return until the ac is shut off. I have tried to pin point the noise but have not had much luck. It would seem like if one of the ac components is failing, the noise would be there with ac on, not off. Does anyone have any idea of what or where to look?

[Hitchhiker]

Sounds like some issue with the belt or the mechanisms associated with it. Maybe the idler tension pulley bearings or AC compressor bearings? Could be a glazed belt too. I suspect a close inspection while the noise is present will reveal an obvious defect.

[edgray]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">It would seem like if one of the ac components is failing, the noise would be there with ac on, not off. </div></BLOCKQUOTE>
AV42: Your statement above is a good assumption, but unfortunately it is not necessarily correct. The noise is probably the bearings in the compressor clutch failing, and they can be loudest when NOT under load. Get to a Workhorse ASC and have a professional diag. the source of the problem while you are still in warranty. Compressor replacement is not cheap! IMO, it will not "hurt" anything to run AC on way to shop to avoid the screeching. ED

[TandW]

Good call Ed! But he needs a way to keep the clutch energized without building overly high, high side pressure. The man will lose the compressor. These aren't amenable to clutch replacement. I went about 200 miles with a bad clutch before it disintegrated. Good luck av42!!

[new-to-rving]

can you descripe the noise, is a scrape, growl or moan, any click to it as you switch on and off the a/c. i suspect the compressor clutch plate end gap is too close and dragging, if you lift the inside cover the compressor is located on your left looking at the dash. you may be able to see this problem with the engine running

[edgray]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">i suspect the compressor clutch plate end gap is too close and dragging, </div></BLOCKQUOTE>
new-to-rving: thanks for joining iRV2.com and sharing some of your mechanical expertise.

Can you tell us if the "end gap" is adjustable? Or, if this condition exists, does it require compressor replacement to eliminate the noise? Thanks, ED.

[knebrdr]

Hello,
This definitely sounds like a compressor clutch bearing failure.
Now to add a little fuel to the fire. Two other threads are currently discussing correct belt length. Was your 1080 length belt ever replaced with a 1031 length belt? I have seen numerous a/c clutch bearing and idler pulleys ruined by a short belt. Short belt, more tension and something has to give.
Weak a/c clutch bearings or incorrect belt replacements?
Randy

[new-to-rving]

well of coarse there's a special tool for pulling to clutch end plate, but the gap should be roughly .20 to .30 inch gap. the reason i think it is not the bearing, for the compressor shaft or the pulley is weather the compressor is on or off the pulley bearing is still loaded by the belt. and if it was the compressor bearings the noise would get worse with the a/c on. hope that helps.

[av42]

Thank you everyone for your replies. I took edgray's advice and the motorhome is currently at Workhorse dealer. I will post what they find when I get it back.

av42

[Jeff H]

Hi, any news on that loud noise?

[new-to-rving]

hey yeah what's the news did the dealer repair or replace your compressor? what has happened? did they get right on it or are they given ya the run around?

[av42]

The noise did turn out to be the compressor and workhorse did ok the dealer to replace. When dealer tried to order the compressor they were told it is on national back order and will not be available until after the 3rd week in Jan., at the earlist.