Need help with Water Pump/ Pump Pulley

[dbreid]

All,
I have a 1984 K30, with a 7.4L Quadrajet motor in it. It is an SM465 if it makes a difference, and it has factory A/C.

I was having trouble with the clutch fan impacting the fan shroud when I was wheeling, so I shelled out for a nice dual fan Flex-a-lite setup. Very nice rig, with thermal sensors, dual speeds, etc.

Now, I go out today to install the thing, and despite my measuring, it is too thick! It fits the radiator itself fine, but the water pump and the associated pulley sticks out too far from the motor. Arg.

I am not a super chevy encyclopedia, but my guess is that there is a different water pump/pulley combination that sticks out much less. Perhaps a water pump from a NON A/C truck? I just removed the A/C (intact, I might add), so I don't mind swapping to a different pulley setup, and I have no problem buying a new water pump, etc. However, I just don't know which one to ask for at the parts store.

Also, how much of a pain is it gona be for me to get a pulley to match it? Can I buy those from the dealer, etc?

Thanks in advance.

-Dan

 

[dbreid]

So I have been reading up some more (it just got dark, so I stopped working on the truck) and it appears that there are "short" and "long" water pumps. It also appears that all the BBC (After 69 or so?) motors except Vettes have "long" water pumps.

It also seems that I can pick up a short water pump from Weiand or Edelbrock, etc (at a premium price, of course).

My new question is:

How much shorter is the "short" water pump from the "long?"

Thanks!

-Dan

 

[dbreid]

Looks like they are 1 5/16" shorter.



http://www.edelbrock.com/automotive_new/mc/water_pumps/water_pumps_main.shtml

 

[UPS]

If you go with a short water pump you will have to get short brackets for the alternator and the power steering pump.

I was told by my local GM dealer the part #'s for the pulleys were discontinued in 1975. If you find out otherwise please send me a pm.

Trans dapt and Spectra sell painted and chrome steel pulleys. Year one (yearone.com) has the pulleys. Original parts group (opgi.com) also sells them.

V belt short water pumps were used from '65-'68 in GM cars and until '72 in trucks.

For you to use your power steering pump you will have to buy an aftermarket bracket. Zoops (zoops.com) sells them (part # sum-340300 at summit.com $104.95). To use this pump brkt you will need an add on 1 groove crank pulley Spectra# 865-4478 Trans Dapt# TRD-8617 black or TRD-9817 chrome (6.8" diameter 2" spacing) I am not sure of the GM part#.

You may be able to change over to the old style saginaw power steering pump and use an original GM bracket. I haven't tried this so I don't know if it will work.

The alternator bracket that I bought is part # sum-420103 ($74.95 at summit.com) or use the original GM brkts if you can find them, both will move your alternator from the passenger side (long water pump side) to the drivers side (short water pump side).

I just bought these brkts from summit yesterday. I will be trying to use a 2 groove crank pulley from a '67 427 vette (part# 3874414), the matching 2 groove WP pulley (part# 3900434ab) and a add on pulley from a small block if I can make it work. I hope to be installing both brackets and pulleys some time next week.

I haven't used this combo yet so I don't know if it works, if anyone has any info otherwise please let me know.

If you need any more info PM me.
Mike

 

[dbreid]

Yeah... I was kinda worried about the other pulleys. I took the water pump off this morning, and I am gonna go to the local speed shop and see if they have a short one with pulleys that will work with my current setup (anything is possible). The weird part is that the "long" pulley looks like a deep "hat" with the brim as the pulley. I basically just need a shorter pump, with an equally shorter "hat".

I am hoping that I can find the pulley to work, but from your post, I am less than hopeful.

Sigh.

 

[dontoe]

IIRC, they work better as pushers anyway. Can't ya install it in front of the radiator. Save a lot of aggravation.........

 

[chevyin]

A couple of years ago I installed a dual Flex-A-Lite fan system on my Chevy pickup tow vehicle. It was actually less thick than the stock fan. I don't know what model fan system you are using, but they are all very efficient and are definately the way to go. With an electric fan, you only use the fans when needed, you pick up H.P, and fuel mileage. I could not be happier with my electric fans.

As for installing the fan in front of the radiator, the intructions that came with my system said that it could be done, but you lose about 20% of the efficiency. Most of the Flex-A-Lite systems are big enough to be able to handle that loss, but you should check it out.

Also, if you are having trouble with the engine mounted fan hitting the radiator, I usually check the motor mounts to make sure they are not allowing the engine to shift enough to let the fan hit the radiator.