Oil pump issues.

[carguy300]

Got my 68 300 running but no oil pressure. Pulled out sending unit and it was bone dry, I would think there should be some evidence of oil on the end. Pulled distributor and pump shaft, does the drive gear look ok. The pump is new and I had packed it with vasoline before I put it back on. It did sit for several months before I got to start it. Could it have lost its prime. I want to find one of the tools to use to prime it with drill motor. The distributor shaft is 1/8" longer than the old one, I dont think that would be an issue? Any ideas or suggestions I would love to hear. So close to getting this road ready, been a long 2 yrs! Thanks guys.

 

[Boydsdodge]

Your distributor/pump drive does not look right. Is it a two piece drive? Maybe it has collapsed and is turning in the shaft.
This what I am used to seeing. Might just be the angle of the photo or lighting.

 

[carguy300]

No, thats what the whole shaft looks like, didnt take a pic of whole shaft. I am concerned about the wear marks on the hex edges.

 

[carguy300]

The top gear that engages with cam shaft looks good.

 

[Boydsdodge]

I'd grab a new one.

 

[Justin Plant]

Agreed, the hex looks really worn out.

 

[carguy300]

Thats kinda what I was thinking. When I changed out the pump on my other 300, the drive hex didnt look quite that rounded!

 

[Big_John]

IMHO, those are tooling marks on the hex. Not wear.

So, I'd say it's OK to use.... However... Changing to the style that has a radius where the hex meets the round is a good idea. The radiused version is stronger. Yes, I have seen them break. @Boyd 's pic shows one with a radius.

Concerning the no oil pressure, I'd try a priming shaft and spin the oil pump. Remember it has to turn counter clockwise and if you put some oil in the oil filter first, that will help. I like to turn the engine over once I get pressure.

Regarding the longer distributor, does it seat down all the way? Is the whole shaft longer or just the tang?

 

[carguy300]

IMHO, those are tooling marks on the hex. Not wear.

So, I'd say it's OK to use.... However... Changing to the style that has a radius where the hex meets the round is a good idea. The radiused version is stronger. Yes, I have seen them break. @Boyd 's pic shows one with a radius.
View attachment 688632
Concerning the no oil pressure, I'd try a priming shaft and spin the oil pump. Remember it has to turn counter clockwise and if you put some oil in the oil filter first, that will help. I like to turn the engine over once I get pressure.

Regarding the longer distributor, does it seat down all the way? Is the whole shaft longer or just the tang?

I did notice the difference in the shaft ends. The distributor go all the way and seats ok, the whole shafts about 1/8 longer but all seems to go together ok. The motor ran ok but I shut it down pretty quick. I always do fill the filter with oil before I install it. I am going to hand prime it this time, I took out sending unit and have temp pressure gauge! Summit has that style shaft, I can drive to arlington tx, tomorow and pick one up. Thanks again.

 

[3175375]

Have you primed the pump? Spin the pump and turn on the ignition and have a friend watch the oil pressure light turn off…

 

[halifaxhops]

If a SB the pump can be shifted just enough to not work, seriously.

 

[carguy300]

My idiot lights dont work yet, put a pressure gauge in place of sending unit temperarly to verify reading.