[allenga]

Hi Guys, got the new clutch on, new belts, belts tight, and I have squealing and some slippage when I accelerate.

Is this a known problem when you put a big heavy clutch on. Any resolution?

Thanks

[71 T/A]

I use the same clutch on my 69 GTO and it is quiet.

[400 Lemans]

http://forums.maxperformanceinc.com/...d.php?t=801899 If the ps belt is to narrow it will squeal no matter how tight it is. Make sure you have the correct width belts.

[Schurkey]

Hayden 2797 is a severe-duty clutch.

Probably not appropriate, depending on the fan used with it. You almost certainly have the wrong clutch for the application.

The typical automotive fan doesn't move enough air to use with a severe duty clutch. The clutch will never release. Therefore, excess load on the belt. It may be that changing the belts or pulley mods may help.

[allenga]

My Gates belts are 13/32" according to the catalog. What is the width measurement of the wider belt I need.

[77 TRASHCAN]

The severe duty clutch is not the way to go, or needed. Been there.
Your pulley may need some emery cloth scrubbing on it. Sometimes wear just polishes them very smooth, can be part of a squealing issue.

I sold auto parts years ago. Almost all GM vehicles used all same width belts. Ford did not. Your belt part number should start with the bumber "7". Belts with "9" part numbers are too fat for most GM applications...

That severe duty clutch can really tax your belt's intended load. Put a standard clutch on your car, you will laugh at how different it will be...

[allenga]

Originally Posted by 77 TRASHCAN

The severe duty clutch is not the way to go, or needed. Been there.
Your pulley may need some emery cloth scrubbing on it. Sometimes wear just polishes them very smooth, can be part of a squealing issue.

I sold auto parts years ago. Almost all GM vehicles used all same width belts. Ford did not. Your belt part number should start with the bumber "7". Belts with "9" part numbers are too fat for most GM applications...

That severe duty clutch can really tax your belt's intended load. Put a standard clutch on your car, you will laugh at how different it will be...

I had a standard duty clutch and it did not do anything. When this clutch engages the temp gauge drops visibly.

[Schurkey]

Originally Posted by allenga

I had a standard duty clutch and it did not do anything. When this clutch engages the temp gauge drops visibly.

First Guess: You need a different radiator. And a different fan clutch. But of course, that'd just a guess.

[400 Lemans]

[QUOTE=allenga;6022134]My Gates belts are 13/32" according to the catalog. What is the width measurement of the wider belt I need.[/QUOTE The top of the ps belt should be flush with the outside of the pulley. The narrow belts will set down in the pulley and arent correct. 17 series belts are the wide ones and 15 series are the narrow ones like the alt uses.

[Formulas]

There is basically 3 levels of clutch fans for our cars standard , heavy duty , then severe duty

Basically std. was for non a/c cars and heavy duty for a/c cars, severe duty mostly used for trucks and police.

Std. Doesn't have a thermal coil on front
Heavy duty has a coil on front and a little more fin size
Severe duty has the coil and is double thickness in fin area

.

[JSchmitz]

I run a severe duty clutch with no problem or slippage. Big difference in cooling vs. heavy duty.

[Formulas]

I run the severe on a 455 with a low RPM cam and 2.73 gears no belt problems but the darn thing never seems to let go

[68 Firebird]

2797 is a great fan clutch. had no issues with belt slippage or squeal. I do have correct wider belt on power steering pulleys. I am trying a 2731 fan clutch right now since it moves fan 3/4" forward deeper into shroud. Gerry

[Schurkey]

Originally Posted by Formulas

There is basically 3 levels of clutch fans for our cars standard , heavy duty , then severe duty

Basically std. was for non a/c cars and heavy duty for a/c cars, severe duty mostly used for trucks and police.

Std. Doesn't have a thermal coil on front
Heavy duty has a coil on front and a little more fin size
Severe duty has the coil and is double thickness in fin area

.

Sort-of true.

Centrifugal clutches--which you incorrectly call 'Std", are complete junk.
Standard clutches have a thermal coil, and are intended for fans with less than 2 1/2" of blade pitch. Pretty-much all automotive fans are to be used with standard thermal clutches.
Heavy-duty and Severe-duty are for fans with more than 2 1/2" of blade pitch. There are a few automotive fans that fit this category, but not many. Without the extra blade pitch they'll NEVER FULLY RELEASE. The fan will spin faster--potentially beyond it's rated RPM, noise will be greater, and fuel economy will be less. Might as well remove the clutch and just run an aluminum spacer.

Originally Posted by JSchmitz

I run a severe duty clutch with no problem or slippage. Big difference in cooling vs. heavy duty.

Because the clutch never disengages properly.

Originally Posted by Formulas

I run the severe on a 455 with a low RPM cam and 2.73 gears no belt problems but the darn thing never seems to let go

Yup.

Originally Posted by 68 Firebird

I am trying a 2731 fan clutch right now since it moves fan 3/4" forward deeper into shroud.

How much of the fan is in the shroud now? Typically, they recommend no deeper than 1/2 in, 1/2 out. 1/3 in, 2/3 out works well, too.

[68 Firebird]

with the 2797 it was 1/3 in and 2/3 out. this worked well. with the 2731 its 1/2in half out and still works quite well. weird thing is how air blows away from fan. with 2797 air exit straight back toward motor, and with 2731 it exit radially around fan tips. only changed was fan clutch, same fan. Gerry no complaints with either. just tried something different to optimize fan position in relation to shroud. Heck maybe I was fine before???

[JSchmitz]

Originally Posted by Schurkey

Because the clutch never disengages properly.

Wrong Mr. Expert. My fan will pull hard for a short while after I start the car and then go dead silent. I can then hear it engage and disengage while I'm driving the car in hot weather. In cold weather you can hardly hear it.

[chiphead]

I had belt squeal with the severe duty fan clutch. Never could get rid of it and I thought I tried everything. Part of the issue is extra load from the clutch, and part of it is pulley misalignment made my situation worse. Didn't realize how off pulleys were until I mocked up my new setup. Use of smaller diameter AC WP pulley doesn't help squealing, as it tries to spin the fan even faster than non AC pulley.

I agree that the heavy duty clutch and a better radiator are the way to go. I saw the biggest gain going to a aluminum radiator. My new setup will use the 11 bolt pump, HD clutch and corrected pulleys. Big hopes that it cools better and solves belt squeal.

[allenga]

I got a long screwdriver with some self adhesive sand paper wrapped around the tip. While the engine was running, I inserted the tip of the screwdriver in the pulley groves to roughen up. Now when I rev, no squeal. Will see how it goes.

My 2797 does engage and disengage. I can hear the difference and the temp gauge drops almost immedialty when it engages.

Great spirited debate!

[allenga]

Originally Posted by allenga

I got a long screwdriver with some self adhesive sand paper wrapped around the tip. While the engine was running, I inserted the tip of the screwdriver in the pulley groves to roughen up. Now when I rev, no squeal. Will see how it goes.

My 2797 does engage and disengage. I can hear the difference and the temp gauge drops almost immedialty when it engages.

Great spirited debate!

What a mess. 2797 started slipping. Tried 2747 (heavy duty) also slips. Now I am back down to puny little standard duty 2705.

I sanded down the groves on all pulleys and tried new belts. No dice.

[antique69lemans]

Are you using a cogged belt ? They seem to get better traction. Maybe that belt is glazed.