Oil Pump Gear Swap

[Hauula Pan]

I have a question about changing the Pinion & Oil Pump Drive gears on my 1952 FL. I know that the 1936 - 1972 used a 5 tooth pump gear driven by a 25 tooth pinion gear & the 1972 & later Shovels used a 6 tooth pump gear driven by a 24 tooth pinion and they can be swapped in 1954 and later motors without any machine work, they are a drop in swap. My question is can I put the 6/24 gear set in my 1952 FL or not ?????

[kitabel]

Not without changing the entire pinion stack, including the shaft. The 1939-53 (splined) and 1954-57 (tapered) pinion shafts are all the same 1" diameter & same taper so it's do-able, but the wheels have to come apart.
Baisley makes even faster gears, but IDK if they make early, and $$$.

[Hauula Pan]

Thanks for the info. Guess I'll be sticking with my 5/25 gears & putting up with the damn oil light coming on.

[kitabel]

Well, pumps don't really go bad easily.
What pump do you have, what weight oil?
Changing the pump speed is only 1 method. The more common one is a later pump (if yours is the original 1952).
The 1968 (aluminum) shovel pump is about 15% more volume due to thicker gears, which means more pressure at every speed up to the relief valve setting.
IIRC some case mods are needed, and the -68 driveshaft.
Heavier oil will raise the pressure at all speeds, but again only up to the relief valve limit.
Some pan motors may be wasting pressure in the rockers due to loose blocks, mis-matched parts, etc.
I suspect, but don't know for sure, that the rockers can do with somewhat less oil, and restricting them will mean more pressure in the entire system. It can be done at any point between the case and the rocker box (case deck, base flange, head gasket, block seat) but I'm not sure it's safe.

[Hauula Pan]

My pump is the original 1952 & I really don't want to run a later model or after market pump. I was thinking that changing the drive gears would not be noticeable & I hoping that I could improve my oiling without losing the original pump. But since the 6/24 gears only fit 1954 & later I'm out of luck as far as an easy fix is concerned. I run 60 wt. non-synthetic oil. I don't think I really have an actual problem with the oil circulation as I have oil returning to the tank. Its just that the light comes on after the engine warms up & takes more & more RPM to put it out until eventually it just stays on. I know pans are notorious for this, especially when using an after-market sending unit, & since the later gears won't work & I don't want to tear into the motor just to change the drive gears, I guess until I can find an original sending unit I'll just have to put up with the light coming on. Thanks again for the info. on what years the gears fit, I didn't know when they changed from the splined to tapered shaft. I did check out Baisley Performance & they only have late model gears. No quick easy fix for the 52.

[steinauge]

IIRC S&S sells a 6\24 gearset to fit the 6 spline pinion shaft.?

[kitabel]

Yup - only $97.80 (plus the pump gear).

[Hauula Pan]

I checked with S&S & they do have a 6/24 gear set that will work on the 1952's splined shaft. For anyone else interested the part numbers & prices are. 33-4237 for the 6 tooth pinion shaft gear @ $97.80 MSRP and 33-4230 for the 24 tooth pump drive gear @ $25.03 MSRP so its $122.83 for the set. Before taxes which of course vary greatly from State to State. Thanks for the info. on what years fit what & the tip about S&S having them. If I had a 1954 or newer pan I could just throw in a set from an old shovel motor which plenty of friends have laying around, but for my 1952 I have to go with the pricey S&S stuff. Oh Well I Love the old gal & she's worth it. Keep the old iron on the road guys & gals its getting scarcer every year.