Pulley types and alignment

53a1 · Post by **53a1** » Sat Feb 20, 2010 7:33 pm

Finished with installing the water pump and the water pump and crank pulley don't seem to be aligned. I wondering if I put the correct type of pulley on the crank because the front groove is wide and it throws off the alignment with the water pump pulley.

In the picture I put a straight edge on the water pump pulley to show what's going on. The end of the pulleys are almost aligned but because of the offset of the wide V groove on the crank pulley the belt rides crooked.

Thanks for looking.

Zane · Post by **Zane** » Sat Feb 20, 2010 7:57 pm

Sounds like you have a civilian crank pulley, the pulley v grooves is different on a civilian pulley one wider than the other, military grooves are the same size. Measure the width of both grooves and compare, its hard to tell in the pic just be looking,. Hope this helps

53a1 · Post by **53a1** » Sat Feb 20, 2010 8:58 pm

Thanks Zane. What about this pulley? It came off an M38 (MC engine). The grooves are the same size.

rdsar2k · Post by **rdsar2k** » Sat Feb 20, 2010 10:41 pm

The second one looks correct. I don't know if u have them but my pulley guard had to have the spacers between the pan and the guard to clear the pulley. I used all thread couplings drilled out for spacers and they were perfect fit. About 3/4"long.

OKCM38CDN · Post by **OKCM38CDN** » Sat Feb 20, 2010 10:48 pm

Are you using a rebuilt water pump?

If so the pulley needs to be pushed on another 1/4 to 1/2 inch... for some reason the pulleys are not pushed on the correct amount... do this and all should be good...

Measure from the front of the block and match up both pulleys with the same diastance...

I had to do mine that way... the rebuilds are wrong...

Hope this helps...

53a1 · Post by **53a1** » Sun Feb 21, 2010 11:26 am

Thanks for the help.

This pulley looks like it will line up perfect with the water pump, in fact it came with the water pump! Also my bolt-on timing marker now fits with the new pulley.

The story is when I bought my 24v parts the guy threw in the MC block that the 24v stuff was installed on. This one of those sweet deals you run into once in a blue moon.

I've used so many parts off that MC engine including the pulley guard & spacers, gen mount and water pump. The water pump was new and original. Now it looks like I'm going to use the pulley that also came with the engine. For some reason I thought the diameter was incorrect because it is wider than the one on it now but based on what you guys are telling me it's the correct one.