72 CJ5 water pump issue

[DaveB]

My friend's 72 CJ5 lost its water pump after all these years so I went to pick one up at AutoZone. They didn't even have one listed for that year so I grabbed one for a 77 thinking all 304 AMC engines are the same. Well I was wrong. I took the new pump up to his ranch this morning to swap it but before I put the new on in I did a bunch of measuring to make sure it was a good fit. Everything looked fine except that the old 72 has a shorter shaft. The new pump would have put the fan too far forward and none of the pulleys would have lined up. So now I have to try and figure out what to do. I could use the newer pump but I would have to change the crank pulley, the alternator mounts and possibly the fan pulley. I am going to try and find the right one but 72 was a weird year. Its the first year that AMC owned Jeep and when I restored the Jeep 6 years ago most places had the wrong parts for a 72. I think that Jeep tried to use up the old Willys parts they had laying around because I could find some of the parts by looking at older versions of CJ5s. Has anyone got some suggestions ?

 

[Mouse]

Quadratec shows a water pump: https://www.quadratec.com/products/917104_16.htm

Rock Auto is listing a pump as well for $32.89.

 

[DaveB]

Thanks for the reply. I went to the quadratec site and people asked about the length. The length they gave is what the newer ones are. On a lot of other sites when I read the reviews for the GMB 110-2908 lots of people said they were too long for the application. I have a 77 pump and the 72 pump so I can verify that the lengths are different. They do list the years its supposed to fit and 72 is listed. Maybe Jeep used something older.

 

[Mouse]

Can you give me the length? A picture might help too. Lots of those old jeep V8 parts are getting hard to find. Do you have a part number?

 

[Mouse]

A quick search on Summit Racing shows two possible hub heights - 4.8125 inches and 4.4375. They show an Edelbrock waterpump (8831) with that shorter hub, but none in stock.

Crown Automotive shows a change in 1973 to the waterpump, so I based on my internet research you need the 4.4375 hub height. Off to look more.

 

[Mouse]

More info:

1971-72 Jeep 304 and 360 V8 engines have hub height of 4.438 (4 7/16) inches

Correct part number (should be): 8122307

Walmart shows one (for $347), but probably not in stock....Thats the story everywhere I look.

That rock auto listing above seems to correlate to the correct part (8122307)

 

[DaveB]

Yes the measurement I get from the gasket mounting surface to the fan hub is roughly 4.5" but since there is an old gasket on there 4.438 sounds about right. If the only option costs $347 I think I my friend would be better off finding the parts needed to swap to the newer parts. maybe then we could install the power steering stuff my son found on a newer CJ. The casting number on the old one is 30657. When I went to RockAuto the part number was the GMB 110-2908.

 

[DaveB]

I went looking for the 8122307 part and nobody has one, out of stock or no longer manufactured. I guess I'll be looking for the newer parts.....

 

[J-mobzz]

Could just have the old one rebuilt?

 

[DaveB]

I would have to see if I can find where to have on rebuilt. Another thought is to shim everything out 1/4 of an inch but I would have to see if that's possible.

 

[Mouse]

I went looking for the 8122307 part and nobody has one, out of stock or no longer manufactured. I guess I'll be looking for the newer parts.....

That looks like the right pump to me

 

[DaveB]

Well after a lot of looking I have discovered that switching to the newer parts requires more parts than expected. The crank pulley has to be changed to get the new stuff to line up however the 72 uses a 3 hole pulley and the newer ones use a 4 hole so I would have to change the damper also. Unless of course I could find a 73 pulley which has 3 holes and is longer. Its looking like it will be easier to have the old one rebuilt. I have tried most of the local guys that sell CJ parts and most don't have them and the ones that do want a lot.