[Ogre]

Can someone tell me what I've got and what I need to fix it? No not that!!!

Anyway, I've got a '71 350 engine that I am getting parts to see if I can get it to run. I just got pulleys for the water pump and crank. First pic is from my '72 350 LeMans 'vert, and the pulleys line up precisely. The second pic is of the aforementioned '71 350, and the crank sits about 1/4" back of the water pump. No need to put a fan belt on it, since it would probably toss it anyway.

Have I got the wrong water pump or wrong crank pulley, and what pulley do I need to fix it? Been struggling with this for about a week.

Maybe 4" vs 4 1/2" water pump, but I only have about 1/4" difference ...

Thanks in advance,
Ogre

[sleepy]

Looks like the balance and crank pulley are different. difficult to see in the picture.

[72blackbird]

How many bolts are on the water pump? If you count 11, it's a correct later model water pump for 350,400, and 455's. If not, someone may have put a 67-earler timing cover on your 350. The first thing I see wrong is you don't have the right balancer on there- it's probably one of those later model hubs they put on 77-78 350P's. The correct balancer is a 7" diameter unit (in your first picture you have a later model balancer also)- it fits 68-77 Pontiac V-8's. The crank pulley also appears to be incorrect as well- too small to match the w/p pulley.

You can buy these balancers new on Ebay, as well as at local auto parts stores for around $65-70. PM me and I'll send you pics.

Geno

[Ogre]

Originally Posted by 72blackbird

How many bolts are on the water pump? If you count 11, it's a correct later model water pump for 350,400, and 455's. If not, someone may have put a 67-earler timing cover on your 350. The first thing I see wrong is you don't have the right balancer on there- it's probably one of those later model hubs they put on 77-78 350P's. The correct balancer is a 7" diameter unit (in your first picture you have a later model balancer also)- it fits 68-77 Pontiac V-8's. The crank pulley also appears to be incorrect as well- too small to match the w/p pulley.

You can buy these balancers new on Ebay, as well as at local auto parts stores for around $65-70. PM me and I'll send you pics.

Geno

Hmmm, I may need to talk to PY ... the balancer is part number GME176A straight out of the PY Catalog. I also called and was told that it was "identical" in all measurements to the original balancer, but the order got painted black, so they were being sold cheaper.

Seriously thanks for the info Geno, and you too Sleepy. After reading your posts, I took a REAL CLOSE look and the pulley for the A/C on the "in-process" engine is narrower and there is no gap between it and the balancer. I'll have to remove the pulley (and maybe the balancer) and get some caliper measurements to see what the difference is.

And Geno please send me some part numbers, as I have been unable to find them in any parts stores. All I've found are the $319 version in Ames catalog for a '71 engine ... Ouch!! PM sent ...

Thanks Guys. I let you know what I discover.

Ogre
BTW, Geno ... the water pump is an 11 bolt with a 4 1/2" depth and not the 4" depth pump.

[72blackbird]

Ogre,
The part nos. for the pulleys are no. 481039 for the crank pulley and no.480509 for the A/C pulley. The OEM balancer actually is about 6 3/4" in diameter, part no. 477682- it's substantially larger than the later model hub-style unit. There is also a ring that goes over the crank pulley and is 4 3/4" in diameter.

The best source for this whole assembly is the boneyard, where you could get everything fairly cheap. But I would still buy a new balancer, as the old ones' elastomer is probably worn out already.







Geno

[Ogre]

Originally Posted by 72blackbird

Ogre,
The part nos. for the pulleys are no. 481039 for the crank pulley and no.480509 for the A/C pulley. The OEM balancer actually is about 6 3/4" in diameter, part no. 477682- it's substantially larger than the later model hub-style unit. There is also a ring that goes over the crank pulley and is 4 3/4" in diameter.

The best source for this whole assembly is the boneyard, where you could get everything fairly cheap. But I would still buy a new balancer, as the old ones' elastomer is probably worn out already.

Geno

Thanks for the pics, Geno. Even though my part numbers are different, the dimensions are the same as yours. (Junk yard finds don't always have the same numbers even though the dimensions are the same.) My part numbers are: 1) Crank pulley - 9790842YB, 2) A/C pulley - 9790843YC, 3) water pump pulley - 10004850YY. And I have another identical measurements water pump pulley - P/N 481040XT. As I previously stated my balancer is from PY and the measurements (depth and diameter) are the same as the one on my 'vert.

My problem is not with diameters, but the depth, and it appears to be the A/C pulley (probably off of a chebby or some other gross thing). On my 'vert, I have about a quarter of an inch betweeen the A/C pulley grooves and the balancer, but on the second engine I don't have any clearance. [SEE PICS ABOVE] It appears that I need an A/C pulley which is deeper (by 1/4") than the one I have.

Anybody got any other ideas, other than throw them all in the trash and get a complete new set ($319), or keep junking?

Any (welll most any) input welcome.

Thanks,
Ogre

[AGTO8U]

The misalignment issue looks like you have the pre '68, 4" hub height type water pump, and crankshaft pulleys designed for a 4.5" water pump. A solution would be to get some crankshaft pulleys from the boneyard off an engine with a 4.5" water pump (looks like the crank pulleys in the 1st photo is what you want). Or try to find a 4" hub height water pump and keep your existing pulleys. If you go the water pump route, casting #9786351 has a 4" hub height.

["QUICK-SILVER"]

Last summer a guy came by the house with the same problem. Water pump pulley was off about 1/4". He had all kinds of part numbers and measurements, so we went out to the shed and started digging. It didn't take long and found exactly what he needed, a water pump pulley about 1/4" different than what he had. And yes it was Pontiac.

Now the bad part. I don't have the part number or application, only know it does exist, and came off a Pontiac V8.

Lay your water pump pulley down and measure the depth on it. (thats how we did his)Then post what you got and what you need. Somebody will have one.

That's if water pump pulley is all that's out of line.