I ran into a problem that has me stumped . My Father-in-law put a TCI frontend in his 64 Chevy II , changed over to a rear sump oil pan and a new oil pump and pickup . I went over to address a wiring issue for him , got that handled and proceeded to crank the engine (sbc) . Engine cranked with no problems , but had no oil pressure , OK , he didn't prime or pack the new oil pump , so I figured it just hadn't pick up the oil yet . I pull the distributor , use a priming tool , primes right up 40+ psi . So I figured we were good to go , reinstalled distributor and cranked engine no problem , but still no oil pressure ! I pulled the distributor back out and compared it to the priming tool ( made from an old distributor ) and discovered that the shaft had to be about 5/8" further into the housing to engage the oil pump shaft ! WTF Are there different oil pump driveshaft lengths ? (he reused his old one) Are there different length shafts on oil pumps? Maybe a BBC oil pump? I didn't install this oil pump and don't know for sure if he did everything correctly or not (it's pretty straight forward!) All I do know is that the oil pump drive shaft is too short to engage the distributor . Any suggestions ? Terry

Some MSD distributors have an adjustable collar, so you can set the depth.

If he didn't change intakes, the difference has to be in the new pump or drive shaft huh??????

But with 5/8" difference I'd be afraid it may stab the oil annulus too far into the block and miss the porting.....

Time to check part#'s on the pump and rod

The front sump Chevy II Oil pump has it's own drive shaft. It's different then the rear sump SBC shaft. I can't believe he had good pressure with the front sump, I never had any luck with it on my duece.

Jeff

Terry,
Do you have the part number of the oil pump he bought ? The online Melling catalog shows a different part number shaft for ChevyII, are you sure he reused his old one ? I can try to remember to look in the catalog at the shop in the morning and see what is different about it. I wont mind if you call me as a reminder, if Thursday is as crazy as today was I will probably forget :(

301-843-5700

No , I don't have the part # , and I didn't know that the Chevy II o/p driveshaft was different than other sbc ! Learn something new everyday ! That would explain the dizzy not engaging it . I am certain that he reused the driveshaft that was in the motor before the pan and o/p swap . I will do some investigating on this , now that I know what I'm looking for , if I run into a wall I'll call you Bill , Thanks . Got to love this place ! Terry

The online Melling catalog shows a different part number shaft for ChevyII, Thanks Bill, for the info. Another bit of info for the 1K memory.

The front sump Chevy II Oil pump has it's own drive shaft. It's different then the rear sump SBC shaft. I can't believe he had good pressure with the front sump, I never had any luck with it on my duece.

Jeff

We used to road race a 64 with a front sump pan and had no problems at all with oil pressure.

Terry,
Just looked at the Melling book. The ChevyII shaft is .660" shorter than the "normal" shaft. The pump is definitely a seperate part number too. I think the solution will be a Melling IS55E shaft.

HTH

Hmmm, what about measuring the length of the dist shaft and compare it to the depth of the oil pump drive thru the distributor hole? At least you know what ballpark you are in.

alan

You are definitely using the Chevy II oil pump driveshaft, replace that shaft with the longer rear sump driveshaft and your problem will be solved. I went through the same problem 40 years ago only in reverse when installing an LT1 in a 62 Nova, I could not seat the distributor against the manifold because the driveshaft was too long. It was at that point that I learned that Chevy had different lengths on the oil pump driveshaft, I put in the correct one and the distributor fell down to the intake sealing surface.

Thanks Bill , I came up with the same conclusion in my research . When comparing the distributor to my priming tool , the difference was a little over 1/2" , a little more info to file away ! Thanks again guys , yet another time that you guys come through in a pinch ! Terry