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So, with me sifting through the information about our cars, there is one thing I have yet to find a straight answer to. So, I know that there is a short water pump (~5.1”,) a medium length (~5.6”,) and a long one that is somewhere in the neighborhood of 6”. From my understanding, the short pump was is on small blocks with no ac. The long pump is used on small/BB cars with HD cooling, AC, or both. Now, where does the middle length pump come in, and what pulleys does it use?! Is it for HD cooling with no AC? I know there are/were cars that had HD cooling, but did not have AC. Is this where the middle pump comes in? I ask these questions because I have a Flowkooler aluminum pump in their “short” (don’t be confused) 5.6” pump. They also offer it in a 6”. BUT- no 5.1” option available in an aluminum pump that I can find. So, with all of that being said, what does one use to run the 5.6” pump on a car with no AC, but does have power steering? Seems to me that the mid length pump is kind of a strange bird length that isn’t typically used. Maybe I have a complete misunderstanding of what works with what, but I was hoping we could make a post that is a definitive answer to other people trying to figure out their pulley systems like myself.
You are not correct, but don't feel bad as most water pump vendors are not correct either. Unfortunately, the information on the web assumes that the only cars Oldsmobile made are 1970-72 A-body cars. The actual water pump application depends on the year, model, and accessories. The 1964 cars use a one-year-only pump due to the driver side inlet. Both A/C and non-A/C used the 5.1" pump.
All 1965-up cars use the "normal" passenger side inlet. All 65-67 cars also used a 5.1" pump for both A/C and non-A/C applications.
1968 is where is starts to get messy, with 5.1" pumps on non-A/C cars and 5.6" on the A/C and HD cooling cars. By 1970, Toro motors used the 6.1" pump.
1971 saw the change to the smaller inlet and 5.1", 5.6", and 6.1" all used depending on model and application.
By 1973, the non-A/C cars got the 5.6" and the A/C and HD cooling got the 6.1" pumps.
There is a chart on the web that tries to list application, length, casting number, and part number, but there are errors in that chart. I've been trying to build a correct one.
You are not correct, but don't feel bad as most water pump vendors are not correct either. Unfortunately, the information on the web assumes that the only cars Oldsmobile made are 1970-72 A-body cars. The actual water pump application depends on the year, model, and accessories. The 1964 cars use a one-year-only pump due to the driver side inlet. Both A/C and non-A/C used the 5.1" pump.
All 1965-up cars use the "normal" passenger side inlet. All 65-67 cars also used a 5.1" pump for both A/C and non-A/C applications.
1968 is where is starts to get messy, with 5.1" pumps on non-A/C cars and 5.6" on the A/C and HD cooling cars. By 1970, Toro motors used the 6.1" pump.
1971 saw the change to the smaller inlet and 5.1", 5.6", and 6.1" all used depending on model and application.
By 1973, the non-A/C cars got the 5.6" and the A/C and HD cooling got the 6.1" pumps.
There is a chart on the web that tries to list application, length, casting number, and part number, but there are errors in that chart. I've been trying to build a correct one.
Awesome. This is exactly what I was looking for. So, if one were wanting to use the passenger side mounted alternator bracket, 5.6” pump, and power steering, what pulleys would be required? Mine would be a 68 application.
Awesome. This is exactly what I was looking for. So, if one were wanting to use the passenger side mounted alternator bracket, 5.6” pump, and power steering, what pulleys would be required? Mine would be a 68 application.
And that's your problem. The 1968-69 cars with passenger side alternator (non-A/C) used the 5.1" pump, unless you got HD cooling, which was pretty much the W30, W31, and H/O cars.
The water pump pulley for that combo is the unobtanium P/N 401462 "KA" pulley.
Crank pulley is 399402 "KB"
PS pump pulley is 399403 "KG"
You may find that it's MUCH easier to switch to the 5.1" water pump and use the readily available 399401 "KE" water pump pulley.
And that's your problem. The 1968-69 cars with passenger side alternator (non-A/C) used the 5.1" pump, unless you got HD cooling, which was pretty much the W30, W31, and H/O cars.
The water pump pulley for that combo is the unobtanium P/N 401462 "KA" pulley.
Crank pulley is 399402 "KB"
PS pump pulley is 399403 "KG"
You may find that it's MUCH easier to switch to the 5.1" water pump and use the readily available 399401 "KE" water pump pulley.
Yeah I kinda figured it’d be something like that, my luck haha. Though I know it’s not super beneficial, I’m stuck on the aluminum pump. I have multiple KE pulleys, along with a 5.1” cast iron one I could swap in. May end up having to do that. Sure would be easier haha
To further elaborate, 1968-70 used two different shaft length water pumps.
One was for all non AC HD cooling cars, and the other was for AC and HD cooling cars.
In 1968-69 the AC HD water pump casting number is 400269.
In 1970 the standard water pump is casting number 404584.
The AC HD water pump is 404847.
All models used it, so not just limited to A body.
However in 1971 they decided to offer three different water pumps.
The standard was casting number 408328
The AC was 407586, and
The HD pump was 408329.
As far as making the pulleys line up the "KM" offset water pump pulley was used for the HD cooling setup.
The Chassis manual in I believe the 6K section will display the water pump lengths.
Hope this helps.
All 1965-up cars use the "normal" passenger side inlet. All 65-67 cars also used a 5.1" pump for both A/C and non-A/C applications.
This was intresting , when i look at Rockauto there are two models. I have replaced the waterpump in my -65 98 w/o AC and
also need to replace the waterpump in my -65 88 with factory air.
This was intresting , when i look at Rockauto there are two models. I have replaced the waterpump in my -65 98 w/o AC and
also need to replace the waterpump in my -65 88 with factory air.
Go back and read the first line in post #2 above. Once again, the RockAuto catalog is NOT a reliable source of fitment information.
Sorry, but that chart is 1) far from comprehensive and 2) incorrect. For example, the 1971-72 W30 cars used pump P/N 231066, which is casting number 408329. That same pump was also used on every other Olds A-body in those years with A/C or HD cooling, not just W30 cars. 408329 is a 5.6" pump. Casting 408328 that is incorrectly shown on that chart is a 5.1" pump. That would be P/N 231065, which is for non-A/C, non-HD cooling applications.
This is yet another example of why you should not trust third party information like that, but go directly to the factory literature.
328 was the standard non A/C, non W-30 pump 5.1" (1)
329 was the W-30 non A/C pump 5.6" (2)
??? was the A/C pump 6.1" (3)
These are easily identified by 1, 2, or 3 castings into body of waterpump. I have seen the 329 with an X instead of a 2. I have also seen a 329 that was 5.1. The 329 pump was also used on big cars without A/C.
328 was the standard non A/C, non W-30 pump 5.1" (1)
329 was the W-30 non A/C pump 5.6" (2)
??? was the A/C pump 6.1" (3)
These are easily identified by 1, 2, or 3 castings into body of waterpump. I have seen the 329 with an X instead of a 2. I have also seen a 329 that was 5.1. The 329 pump was also used on big cars without A/C.
Don W
No, the 1971/72 A-body cars only used two water pumps, casting '328 (5.1") for non-HD, non-A/C and casting '323 (5.6") for the HD and/or A/C cars. The full size cars used the 5.6" for both non'A/C and A/C. Toronados used the 6.1" for A/C. From the CSM:
That drawing is from the 71 Chassis Manual??? and is incorrect. Unfortunately even factory books can be wrong. I went through this multiple times to determine the correct pump for my 71 non A/C W-30. I checked the engine assembly manual, parts books, and actual pumps. Dig deeper and I think you will come up with the same results I did.
