Water pump hub and fan spacer question

[RandyB]

Does anyone know why the cooling system parts diagram shows the water pump spacer "NN" as going between the pump and pulley? I thought it goes between the pulley and fan? and does anyone have a part# for the original, longer hub, that goes on the pump shaft? The hub on new pumps seems short. Thanks in advance

[Cal_Gary]

Hi Randy, and welcome to the G741 Forum! Lots of folks here to help you along so feel free to use the Search engine, or post a new question.
For your fan spacer, I believe it could go in either position depending on pulley alignment. Some M37s have multiple belt sets while others do not. My 8030 manual page 240 shows fan then spacer then pulley.
Gary

[Elwood]

This topic might help: viewtopic.php?f=3&t=3125&p=23827&hilit= ... ion#p23827

[NAM VET]

here is the set up for my four pulley 100 amp alternator. NV
[url=https://postimg.cc/qh7kB0Hv][img]h ... .jpg[/img][/url]

[RandyB]

Thanks for the suggestions guys. I did do a search but didn't see the one where Charles suggested Machining the hub down to 3/8". I think I'll give that a try. At some point mine had the 100 amp system but previous owners converted it to 12 volts and added a one wire GM alternator. They left the 4 groove pulleys on the crank and water pump but used a two groove pulley on the alternator. Both belts were mismatched and way too loose. The crank pulley was loose and cracked down the center, the key was worn into an "L" shape and the keyway in the crankshaft is about twice as big as it should be and it's all boogered up. It seems like most of what I'm doing now is undoing what others have done.

[Cal_Gary]

Yeah Randy, that's what hackers do. We spend a lot of time undoing things that weren't properly done ahead of us....
Gary