Hi, working on rebuilding the 1970 350 for my 1970 Cutlass Supreme. The car originally had AC that I am now deleting. I have changed the water pump to the shorter pump with the 2 groove pulley (as opposed to the original 3 groove), but am using the original 6 blade fan/clutch. I also changed the crank pulley to a 2 groove. I'm using the original P/S pump and 2 groove pulley. I don't have the alternator installed yet. I was just mocking up the front pulley setup and noticed that a few of the fan blades are hitting the shaft/nut on the P/S pump (see photos). I'm assuming that is because the water pump shaft is shorter for the non-AC setup so the fan sits closer to the engine? Trying to see if someone can offer a solution for the fan interference. Is there a different fan (maybe for non-AC cars) that I can just bolt onto my existing fan clutch.

Also, I see that they make a 1 groove pulley for the P/S pump but the diagram for that (at least on the Inline Tube site) shows a 2 groove setup for the belts. Not sure how the one belt would go on without the second groove on the P/S pulley.

Thanks.

 

The pullies are a set. If you change one you have to change them all.

 

Thanks. I'm assuming you mean that I would need to change the PS pump pulley to a single groove? Since I've changed the other two already. I can do that but that will still not fix the issue as the fan is actually hitting the end of the PS pump shaft so replacing the pulley would not change that. Or am I missing something? Also, does someone have a photo or diagram of the belt routing for non-AC cars? All the diagrams I've seen show the AC belt running just around the extra water pump and crank pulley grooves. So, if you eliminated the AC, it still would seem you still need a two groove PS pulley. If you eliminate one groove on the PS pump pulley, how would the routing then work? I have a single groove PS pulley from a 1972 Chevelle with Saginaw pump. Would I be able to use that?

But, again, changing the pulley still doesn't seem to fix the original interference issue with the pump shaft and fan. Seems like I need a diiferent fan?

Thanks. Sorry for all the questions.

 

So I think I found an answer to at least the single groove pulley issue. According to the attached chart, my original AC setup had the alternator located on the driver's side. Without AC, it looks like it gets moved to the passenger side. I'm assuming I'll need a different mounting bracket for the alternator as well.

 

The fan is hitting the pump shaft, not the pulley. Changing the PS pump pulley won't change that. This is why HD cooling cars without A/C still used the longer water pump.

 

As Larry pointed out you need the correct set of pully's. You also may need a spacer on your fan to move it closer to the radiator. I am doing just the opposite and have a spacer if needed. Greg

You can see one here. Greg

 

Different pulleys won't change the length of the PS pump shaft.

 

I assume the spacer is his issue but didn't want to step on Larry's toes. Is this the correct way to fix his problem or is more info needed? Thanks Joe. Greg

 

As I said above, the correct way to fix this is to use the longer water pump the way the factory intended. Spacers will increase the side load on the water pump bearingns.

 

Thanks for all the responses. Greg, how thick is that spacer? Is that aftermarket or custom machined? I think if I just use a spacer that makes up the difference between the long and short water pump shafts, I can continue to use my 2 groove PS pump and leave the alternator on the driver's side. This would just eliminate the AC pump and belt in the AC setup diagram. Would just need the original AC car size belts. All of this would be temporary for now.

Thanks again.

 

Joe, Thanks That makes sense. Was the spacer an original item or just an aftermarket easy fix? A couple engines I have have them.

 

OK I'll answer that. WHY would the factory put something on a motor that would break it? Sometimes on Monday it takes a while. Thanks again

 

The factory never used a spacer with a clutch fan. Read my several posts again. The factory only used the clutch fan with the longer water pump. There was no need for a spacer.

 

Yes that's the conclusion I came up with after reading your posts over. Couple times. Just poking some fun at myself with the reply. Thank you Joe