Fan belt pully alignment? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Chiefdan · 03-27-2021, 12:11 PM

I have a '67 stepside with a GM Crate 350 engine, power steering and brakes. I have noticed that the fan pulley on the water pump does not align with the crank pulley. The fan pulley is about half the belt width in further than the crank pulley. Power steering belt is on the rear notch on crank, fan/alternator in the center notch and the front one is not used. The bolt that screws into the block and holds the alternator bracket on cannot be removed all the way because the fan pulley is in the way. This so far has caused no problem but it isn't correct and it bothers me. Was the wrong water pump used? is there a shim missing behind the fan pulley? Tried to upload photos but it sent me to administrator. Any input will be appreciated.

**kwmech** · 03-27-2021, 12:22 PM

Pics and pulley numbers

Chiefdan · 03-27-2021, 12:45 PM

Quote:

Originally Posted by kwmech

Pics and pulley numbers

I tried to upload photos but it sent me to the administrator for some reason, tried one photo at a time and think they are ok now. The water pump pully has 2 grooves and is part #3995646AH. Crank pulley, I could find no number but is 4" deep and has belt grooves at 1 3/4, 2 1/2 and 3 5/8" from inside out.

**kwmech** · 03-27-2021, 02:33 PM

I'm no expert on the long water pump stuff since there were several combinations with the water pump brackets, BUT I do know that the combinations I've seen have the water pump pulley deeper in that the backside of the pulley is really close to the housing by the water nipple. The crank pulley also looks incorrect in that the spacing from the balancer to the 1st groove is too deep or is missing a groove. Where did you come across these pieces? It also appears that you are using the short water pump PS pump mounts

Chiefdan · 03-27-2021, 02:40 PM

Kwmech, The previous owner put this engine in it. He told me that he used a donor 1971 truck for the power steering, 5 bolt wheels, disc brakes etc. After a time surfing the net I found that the water pump pulley is off a '71 6 cylinder engine. He must have used the pulleys off the 6 cylinder engine. I'm wondering if a stock two groove fan pulley for a 350 would solve my problem? I need the 2 groove so I can keep the inside groove for the power steering.

**kwmech** · 03-27-2021, 05:01 PM

Sounds like you found your problem

03-27-2021, 12:11 PM	#1
Chiefdan Registered User Join Date: Nov 2020 Location: Fredonia Posts: 28	Fan belt pully alignment? I have a '67 stepside with a GM Crate 350 engine, power steering and brakes. I have noticed that the fan pulley on the water pump does not align with the crank pulley. The fan pulley is about half the belt width in further than the crank pulley. Power steering belt is on the rear notch on crank, fan/alternator in the center notch and the front one is not used. The bolt that screws into the block and holds the alternator bracket on cannot be removed all the way because the fan pulley is in the way. This so far has caused no problem but it isn't correct and it bothers me. Was the wrong water pump used? is there a shim missing behind the fan pulley? Tried to upload photos but it sent me to administrator. Any input will be appreciated.

03-27-2021, 12:22 PM	#2
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,389	Re: Fan belt pully alignment? Pics and pulley numbers

03-27-2021, 02:33 PM	#4
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,389	Re: Fan belt pully alignment? I'm no expert on the long water pump stuff since there were several combinations with the water pump brackets, BUT I do know that the combinations I've seen have the water pump pulley deeper in that the backside of the pulley is really close to the housing by the water nipple. The crank pulley also looks incorrect in that the spacing from the balancer to the 1st groove is too deep or is missing a groove. Where did you come across these pieces? It also appears that you are using the short water pump PS pump mounts

03-27-2021, 02:40 PM	#5
Chiefdan Registered User Join Date: Nov 2020 Location: Fredonia Posts: 28	Re: Fan belt pully alignment? Kwmech, The previous owner put this engine in it. He told me that he used a donor 1971 truck for the power steering, 5 bolt wheels, disc brakes etc. After a time surfing the net I found that the water pump pulley is off a '71 6 cylinder engine. He must have used the pulleys off the 6 cylinder engine. I'm wondering if a stock two groove fan pulley for a 350 would solve my problem? I need the 2 groove so I can keep the inside groove for the power steering.

03-27-2021, 05:01 PM	#6
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,389	Re: Fan belt pully alignment? Sounds like you found your problem



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