Fan Spacer and/or Fan Clutch substitute

[Patrick H.]

If I recall, there used to be advertised in the Driveline a nicely machined fan spacer to replace the fan clutch for a Corvette. It looked very much like an original fan clutch hub but was, of course, solid. You could then bolt a fan to it just like you would an original clutch. The only thing obviously "missing" was the clutch unit itself. I checked the current issue and don't see it advertised.

Does anyone recall who made this and if it is still available? Trying to troubleshoot an issue with the orange 72 and I'd like to try a direct drive to the fan to see if it may be the new clutch itself. The regular aftermarket ones are, um, junk so I'd rather not use them if possible.

Thanks for any info you can provide.

Patrick

[Joe L.]

Re: Fan Spacer and/or Fan Clutch substitute

If I recall, there used to be advertised in the Driveline a nicely machined fan spacer to replace the fan clutch for a Corvette. It looked very much like an original fan clutch hub but was, of course, solid. You could then bolt a fan to it just like you would an original clutch. The only thing obviously "missing" was the clutch unit itself. I checked the current issue and don't see it advertised.

Does anyone recall who made this and if it is still available? Trying to troubleshoot an issue with the orange 72 and I'd like to try a direct drive to the fan to see if it may be the new clutch itself. The regular aftermarket ones are, um, junk so I'd rather not use them if possible.

Thanks for any info you can provide.

Patrick

Patrick------


I know what you're talking about but I don't know the source or if they're still available. I've seen them advertised elsewhere, too, but I just don't recall where. However, unless you're planning on possibly leaving it installed, why can't you use the admittedly junky aftermarket type spacer? It should last long enough for test purposes.

What type of replacement fan clutch are you using and which you think might not be performing properly?

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

It is (was) a new GM HD unit (the 1974 style) since that's what is easily available.
We're dealing with a severe overheating problem, and I'm not talking about the gauge. If the car sits in traffic the temp goes up and eventually it pukes a lot of coolant.
The heat underhood is severe and you can't touch the hood when it heats up. We've melted two sets of windshield washer reservoirs. It's HOT in there.

It is not overfilled, and it has new DeWitt radiator, new hoses, new thermostat, new fan clutch, new water pump, and we've tried two new radiator caps (not repro ones, either).
I even swapped the intake thinking it might have a crack underneath causing exhaust to enter the crankcase and increase temps. Nope, no change.

I noted that there was not a lot of air flow at rest, so I wonder if the fan clutch isn't engaging enough. Or, the water pump doesn't work well at low speeds.
I don't recall from last weekend if the fan kept spinning when the car was warmed up but I may have him test that before I try the spacer trick.
We're really at a loss, but he can't drive it around town now.

The last possibility is some sort of internal issue but since we're not really losing coolant when it doesn't puke it, that seems less likely.

Patrick

[Paul O.]

Re: Fan Spacer and/or Fan Clutch substitute

Patrick


Here one is from Corvette Central

http://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000050g~Z5Z5Z528919~P64.95~~~~S3LE0LMJEJ20810276182a~Z5Z5Z5~Z5Z5Z50000050G

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

Hmm. A bit more than I wanted to spend for a testing setup.

[Terry M.]

Re: Fan Spacer and/or Fan Clutch substitute

Patrick,
Did this begin with the water pump replacement? Some rebuilders neglect to closely examine the vanes of the impeller. These vanes can deteriorate from corrosion and thus while the pump spins very little or nothing gets pumped. Sometimes the old pump only has leaks and the replacement has vane issues on one takes several steps back unintentionally. This is something about the rule of unintended consequences.

Just thinking while I am at work.

[Paul O.]

Re: Fan Spacer and/or Fan Clutch substitute

Patrick

A lower priced alternative.

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_aluminum-fan-spacer-kit-mr-gasket_17360040-p?searchTerm=fans+-+accessories+%26+spacers

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

Patrick,
Did this begin with the water pump replacement? Some rebuilders neglect to closely examine the vanes of the impeller. These vanes can deteriorate from corrosion and thus while the pump spins very little or nothing gets pumped. Sometimes the old pump only has leaks and the replacement has vane issues on one takes several steps back unintentionally. This is something about the rule of unintended consequences.

Just thinking while I am at work.

It's the orange car, so as you can imagine a lot of things happened/were replaced before any testing occurred.
It didn't do this 18 years ago when he put it away but it's happening now. I'm to the point where it really has to be something we've replaced and "assUmed" to be in good condition.

So, fan clutch and water pump are on the short list.

[Terry M.]

Re: Fan Spacer and/or Fan Clutch substitute

It's the orange car, so as you can imagine a lot of things happened/were replaced before any testing occurred.
It didn't do this 18 years ago when he put it away but it's happening now. I'm to the point where it really has to be something we've replaced and "assUmed" to be in good condition.

So, fan clutch and water pump are on the short list.

When you drain the coolant, open the block drains -- in spite of what a PITA it is. You just might find a lot of crud.

[Joe L.]

Re: Fan Spacer and/or Fan Clutch substitute

It's the orange car, so as you can imagine a lot of things happened/were replaced before any testing occurred.
It didn't do this 18 years ago when he put it away but it's happening now. I'm to the point where it really has to be something we've replaced and "assUmed" to be in good condition.

So, fan clutch and water pump are on the short list.

Patrick-----


If you're using a GM #88961768, aka Delco #15-4950, that's the best fan clutch ever installed on a Corvette. Unless it's defective, it should PULL AIR BIGTIME. You can tell if this fan clutch is working because it's quite noisy when it's engaged.

Are you using a NEW waterpump (as opposed to rebuilt)?

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

When you drain the coolant, open the block drains -- in spite of what a PITA it is. You just might find a lot of crud.

Been there, done that, flushed it twice now.

[Terry M.]

Re: Fan Spacer and/or Fan Clutch substitute

been there, done that, flushed it twice now.

ok ok ok ok ok

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

Patrick-----


If you're using a GM #88961768, aka Delco #15-4950, that's the best fan clutch ever installed on a Corvette. Unless it's defective, it should PULL AIR BIGTIME. You can tell if this fan clutch is working because it's quite noisy when it's engaged.

Are you using a NEW waterpump (as opposed to rebuilt)?

Rebuilt water pump, can't recall the supplier but I know which store it came from.

I was less than impressed by the airflow when the car was sitting in the driveway running with the hood closed and temps climbing. That's why I'm thinking defective fan clutch.
And yes, that's the one.

[Terry M.]

Re: Fan Spacer and/or Fan Clutch substitute

Rebuilt water pump, can't recall the supplier but I know which store it came from.

I was less than impressed by the airflow when the car was sitting in the driveway running with the hood closed and temps climbing. That's why I'm thinking defective fan clutch.
And yes, that's the one.

Does it have all the foam seals around the radiator and core support?

[Patrick H.]

Re: Fan Spacer and/or Fan Clutch substitute

ok ok ok ok ok

Don't worry, I wondered if after that many years some sludge is still working loose.