I Know I can't possibly be the only one with this problem I am trying(still) to find a AC Delco fan clutch for the Barth and can't pinpoint the exact part #. so far 15-4487 and 15-4949 is as close as i can get. Will use Napa or other only as last resort. any input is very welcome. Have read to many bad post about hayden and a couple outer brands. Only want to replace this one time. Thanks as always Richard

Can't help you find one but I'd be interested to know why you are replacing it.

whoever put this one on put the wrong one on they have 2 different size holes for the water pump shaft it will bolt up but never be true. also there are several different types out there,And I am a stickler for having the correct part. I am redoing the complete cooling system from the radiator back. Quite a bit of work but will be well worth the effort Thanks Richard

Richard,

We should have the same set-up (mine's a '78-454)

FWIW, I went against almost everyone's advice and installed a Hayden Heavy Duty fan clutch.

Five years and 16k miles later, it's still working just great.....I think the heavy duty version might be the key......

For me, the difference between a BIG job and a reasonable job was having ratcheting box end wrenches for the fan blade nuts - just too tight for sockets......

The last one I bought was from Rockauto.com, and had a Delco pn of 15625457. This week, it breaks down to 15-4949 at Rockauto. I have had several different pns supplied by several people I know and trust, and they all break down to this one. It is used on GM 3500 trucks, for example. There is a more muscular fan clutch out there, but it will not fit a standard water pump without some cleverness and machining ability.

Last month, we spent three weeks up and down the coast in record high temps, and the 502 pulled the heavy 4WD toad up several 6 and 7% grades with the needle never even getting up to the halfway mark.

A friend used to have a business of doing Jag engine conversions, and had too many aftermarket clutch failures, including radiator macerations, which he had to cover under warranty. He went back to the GM clutch, and the problems went away.

BTW, how old is the little hose connecting the water pump to the intake manifold? I use a steel-reinforced hose from West Marine. After installation, I wrap it several times with aluminum foil to prevent heat damage.

I can also recommend a Milodon high volume water pump, Water Wetter and a Desert Cooler US radiator.

A big electric puller fan controlled by a thermostat is good, too. Search here for more thoughts on heat soak, etc. If you put in a puller fan, DO NOT use the plastic prongs that stick through the radiator core. Take the time and make metal mounts.

thank you for the info the 4949 it is.I bought a flow kooler pump i am going to try and all the hoses will be replaced in fact the bypass hose rubs on the ac bracket which i have to modify, a slight oversight by gm or barth but none the less they can't be totally perfect or we would have nothing to work on. Does yours have a 502? That is next on the list later down the road. Thanks Richard

quote:

Originally posted by rp's barth:
Does yours have a 502? That is next on the list. Thanks Richard

Yes. I am a 502 lover. Put a hot one in the boat and liked it so much I put a mild torque monster 502 in the Barth. A stroker crank in your 454 might be something to look at, though, if you have the time and do your own engine work.

quote:

the bypass hose rubs on the ac bracket which i have to modify, a slight oversight by gm or barth

Most Barth gassers had aftermarket air conditioning. Gonna have to go out and look at mine to be sure I don't have any rubbing.