CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: dalekerr on March 20, 2020, 11:12:45 PM

Title: Water pump pulley size
Post by: dalekerr on March 20, 2020, 11:12:45 PM

I have a 67 with sbc motor and  I added vintage air. Since adding the air the car runs hot up to 230 degrees while sitting idling  after 10 minutes or so. It never gets above 190 while driving at highway speeds. The car has a new 3 core aluminum radiator with shroud, new 7 blade fan and clutch. I noticed that the crankshaft and water pump pulleys are the same size.

I can rev the motor rpm up and bring the temperature down.

My question is would possibly  changing the crankshaft pulley to a larger size or putting a smaller water pump pulley solve my running hot while idling issue?

Yes the timing is set correctly.

Opinions please

Thanks in advance

Dale Kerr

Title: Re: Water pump pulley size
Post by: KurtS on March 21, 2020, 02:47:19 AM

I'd start with the pulley sizes used with AC vs non-AC cars.
http://www.camaros.org/engine.shtml#PulleySpreadsheet

Title: Re: Water pump pulley size
Post by: z28z11 on March 21, 2020, 04:40:05 PM

I notice you didn't spec what thermostat you are using, 180 or 165 degrees ? Stock water pump, OE rebuilt or aftermarket ?

Regards,
Steve

Title: Re: Water pump pulley size
Post by: dalekerr on March 22, 2020, 01:41:52 PM

180 stock water pump.

Title: Re: Water pump pulley size
Post by: dalekerr on March 28, 2020, 06:41:00 PM

Ok I ordered and installed a new crankshaft pulley 7.25 and a new water 6.3 pump pulley today. This seems to have solved my running hot while idling. The car is now running about 10 degrees cooler while driving and idling. 

I read on another site about pulley sizes and  cooling.