Water pump replacement/air conditioning bypass or fix

65_imperial

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I have owned my 65 Imperial for only a couple of years now but I have run into an issue with finding a new water pump. It has the stock 413 with a/c. When I purchased the car, the a/c was disconnected and the belt just ran from the alternator underneath the water pump rather than from the alternator to the a/c pulley. To add to this, the alternator belt always rubbed on the water pump a bit. As of now, I have been unable to find a brand new water pump to replace the one I currently have. I have never tried to run the a/c, nor do I know the reason for it being disconnected in the first place. My options at the moment are these:

1. Rebuild the stock water pump I have now
2. Find a new water pump that is identical to the old one
3. Attempt to diagnose and repair the a/c system, whether I take that to a shop or not
4. Purchase (if thats an option) or build an idler to attach to the compressor bracket to run the belt properly and not have to worry about the alternator belt rubbing on the water pump at all

I’m open to pretty much any suggestions at this point so any help would be greatly appreciated!

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ok maybe i'm crazy but that looks like every other big block water pump i've ever seen? like 30 bucks from rock auto? I know you have everything apart but a pic of how the belts are routed would help us figure out what may be missing....fixing the a/c will NOT be cheap but as long as the front clutch assembly bearing is good the belts can still go around its pully and freewheel
 
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ok maybe i'm crazy but that looks like every other big block water pump i've ever seen? like 30 bucks from rock auto?
So far everything that I have found has been a different design. I got one a couple weeks ago that I have yet to return from rock auto but it was completely different.

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So far everything that I have found has been a different design. I got one a couple weeks ago that I have yet to return from rock auto but it was completely different.

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What is the difference? I always use a quality brand for an a/c car even if it is going on a non a/c car. If the number of vanes is different, use the new one. From the pics it looks like the new one has more vanes on the impeller and is slightly taller, which may not be an issue. I suggest that you use a good fan clutch. Just my two cents.
 
if bolt pattern is the same and distance from where it bolts on to the hub is the same it should work...hopefully just a beefier newer design? I really cant tell from your pic whether the 413 pump is shorter or it's just the perspective of it sitting slightly behind the new one
 
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I made some crude drawings of how my belts are routed but I left out the power steering as that is not changing anything. I can make some better drawings later that illustrate this much better but the alternator belt, with how it’s been routed, rubs on the old water pump a little bit. The issue with the new pump is that the belt will be pushed forward further and rub even more, which in my case makes it unusable. (I really hope this makes sense. Please tell me what I need to make clearer if need be)

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I think the 413 uses a different part number. I would send it to Cowboy John in FL he does super work.
 
I agree with HalifaxHops....if that is actually an oddball pump, I used John Plaskan (cowboy john) to rebuild one for the flathead 6 Hercules engine in a 1940 Diamond T pickup a couple years ago...does your a/c system use an rv2 compressor? does the front pully on the compressor spin freely? the a/c compressor itself will only spin when power is applied to the clutch, which then locks the compressor crank to the pully...the rest of the time the pully just spins on the clutch bearing(inside pully, outside compressor)...so as long as that outer bearing is ok you can route the belt(s...sometimes its a double belt) around the a/c pully even if the compressor itself has exploded internally...if the bearing's bad you should be able to chase down a clutch assembly for it...on my year the belts go from crank to a/c to alternator...the alternator bracket is slotted for the adjustment....just the water pump uses the idler pully for adjustment...your drawing kinda looked like you were trying to run the alternator belt around the water pump idler too?
 
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I agree with HalifaxHops....if that is actually an oddball pump, I used John Plaskan (cowboy john) to rebuild one for the flathead 6 Hercules engine in a 1940 Diamond T pickup a couple years ago...does your a/c system use an rv2 compressor? does the front pully on the compressor spin freely? the a/c compressor itself will only spin when power is applied to the clutch, which then locks the compressor crank to the pully...the rest of the time the pully just spins on the clutch bearing(inside pully, outside compressor)...so as long as that outer bearing is ok you can route the belt(s...sometimes its a double belt) around the a/c pully even if the compressor itself has exploded internally...if the bearing's bad you should be able to chase down a clutch assembly for it...on my year the belts go from crank to a/c to alternator...the alternator bracket is slotted for the adjustment....just the water pump uses the idler pully for adjustment...your drawing kinda looked like you were trying to run the alternator belt around the water pump idler too?
The alternator belt was not routed around the idler, I made that drawing in a hurry so it’s rather confusing. The pulley on the a/c spins freely as does the clutch, but I can check the condition of the bearings later. As I said I have no idea what the condition of the compressor is internally, but from what I understand so far that shouldn’t matter as long as I do not attempt to run the a/c correct?

I am still somewhat new to the hobby so this is a learning experience for me
 
yes...you can unplug the wire to the compressor clutch to assure it doesn't try to kick in...thats how mine was running for the last 20+ years...finally rebuilt the compressor this summer
 
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