kad36

Is there any benefit to trying to find a water pump that is listed for a 303 engine with A/C? I have a '49 88 with 6 volt A/C and it runs hot in our 100+ temps here on the desert...I plan to have the radiator recored with a 4-tube core this winter and also plan on putting a six blade fan on it as well.
My experience with these older Olds V8's is they have a tendency to run hot in hotter ambient temps (100+)
Any input will be appreciated...kad36

Olds64

Is your current water pump failing? If not, I don't think you will see a significant cooling improvement with a new water pump. Your best bet is having the radiator re-cored and putting a better fan on it.

redoldsman

You could install a water pump from a 54 or later car with AC which might help some. It has 8 blades on the impeller instead of 6 like the regular water pump. I don't think you would see a lot of difference. I might have one in my stash of extra parts but I would have to look for it.

Tedd Thompson

You will probably need a shroud and a 4 core radiator plus a 6 blade fan. This is a add on AC unit we are talking about isn't it? I don't think there were any factory AC systems till 53. Does your 6 volt system support this setup?.... Tedd

Ozzie

As mentioned, don't rush into changing the pump unless the bearing or seal is failing. Your money would be better spent on the bigger radiator and the fan & shroud. Also as mentioned, there were impellers with different numbers of vanes, but these might have been rebuilds or from the '60s as the Olds parts books from the '50s only show one impeller part number for the V-8 engines. It does show a different part number for the pump for the '53 cars with C.A.C. (car air conditioning), but not different for any of the later C.A.C. cars. (As Tedd said, '53 was the first factory A/C.) When we got into the '60s there were H.D. pumps for the C.A.C. cars. They had a larger bearing to better take the belt load from the compressor. These would likely fit your '49 as they do fit my '55. (Some bolt changes may be required.) Also be sure to check other aspects of the engine which might cause overheating such as thermostat, ignition timing, blown head gasket, congested exhaust, fuel/air ratio, etc. You might also check your electrical charging system. Getting that original 6V generator to handle an aftermarket compressor clutch and evaporator blower fan might be quite a load, especially if you like to drive with your lights on at night.

coldwar

Another thing to check out: The lower block water jackets fill with hardened sediment and contribute to hot running. I have seen this, and the amount can be surprising. You can loosely check for this condition by opening both block side petcocks and verifying free flow of coolant. They can still have accumulation in the corners, however. This has been a ongoing early Oldsmobile observation mostly seen during rebuild.

I don't think you will gain much with any water pump change. I can post pics of the three main types if you need it, the radiator really needs to be in tip top shape, especialy in your location. All of mine run hot in hot weather even with factory fan shroud, and reliable 6V Olds hot starting has always been and remains touchy. Best of luck ~

Ozzie

Correct. I too have observed this. It is hard to remove unless the engine is out of the vehicle and dismantled. It can help to remove the freeze plugs, but in general a nasty job. I suspect that it is due to coolant reduction and replenishment, though leftovers from the casting process are also possible. I once inherited it in a Ford engine. Be careful what you put in your cooling system.

kad36

Thanks for all the input...I will recore the radiator and since it already has a shroud I will try to find a six blade fan...kad36

redoldsman

I have a 6 blade fan I bought from Speedway Motors that I took off when I went with the electric fan and shroud. I think it is an 18" fan. I would sell it or you can get one from Speedway and I am sure Summit has then also.

kad36

I will measure my shroud to see what size fan I can use...is the fan you have steel, aluminun or plastic? Thanks, kad36

redoldsman

The fan is steel and is painted black. It is not a clutch fan and is a bolt on. It looks like a factory fan. I can probably dig out the part number and you could look it up on the Speedway website.