2 Weird Oil System Problems

I am in the process of priming my engine and I have 2 odd problems I can't explain at the moment. I primed the engine (drill) and get a solid 90psi, all the rockers oiled in about 20 min, I had a few lazy ones but to be expected. I should say all but 1, this one has been over an hour of drill priming with constant engine rotation, its mate on that rocker assemble went no problem. Can't figure that one out, any help would be great.

Next odd problem,I have a Big m block and have my datalogger sensor in the large 1/2" port in the rear at the bellhousing (driver side) and my guage at the smaller 1/4" port below it. The guage comes up perfect and goes down when the drill is off, the datalogger read the pressure (90 psi) but when the drill is off it holds the pressure!! i varified this by removing it and you could hear a hiss then the display indicated 0 pressure. Re-installed the sensor,hit the drill 90psi, stopped the drill and it held the 90PSI. I turned the engine over 2 full revs to try to release any pressure, nothing. Pulled out the priming tool, pressure still there.

Its like there is a check valve in there or something??

Any help would be awesome, getting frustrated.

Corey

 

Problem #1:
I had a lifter once that the oil hole did not get drilled, maybe you have on too.


Problem #2:
I would take those pipe thread reducers and fittings out of the Big M block and look with a flashlight and a blow gun to try to figure out what is going on.

 

I was hoping that I wouldn't have to pull the manifold but... A little update however, I put the drill on it again this morning before I had to go to work. It ran for about 20min, I pulled the rocker while the drill was on and I was getting "some" oil out the pushrod. It wasn't pouring out but it was there.

 

Do you rotate the engine 90 degrees every now and then while priming?
All those oil galleys need to line up to send oil on to the next point.

 

Yup, rotatated the engine 1/4 turn every couple minuites for damn near an hr. I've had BB Chevy engines that have had a few rockers that are lazy but this is the longest I've ever seen.

Corey

 

Oil restrictors?

 

Yes it has restrictors (.125" pretty big), funny all the rest of the rockers are pouring oil, (more than I would have expected with restrictors).

Corey

 

.125" is really no restrictors.

 

Figured I'd Start big and go down from there.

Corey

 

Wich rocker/pushrod assembly is the laziest one??

 

Number 8 Intake. As of last night I have 2 1/2 hrs of priming on that rocker and virtually no oil. I'm going to pull the manifold and start swapping lifters to see if I have a bad one.

Corey

 

We have a winner!!
I had a bad lifter, swapped the suspect one to a different hole no oil! While old postion has oil with the different lifter.

Thanks for the advice.
Corey

 

Awesome, I'm glad it helped you!

On your other issue, we have 3 of the Big M blocks and also utilize the 2 oil ports in the back fo the block. One for a gage and one for an idiot light. The gages hold psi also but I thought it was the fact that the oil line was too long? You have me thinking now...

As far as restrictor size, over the years we have always used .080" restrictors in our Mark IV, Gen VI and Big M blocks, until this winter... I drilled one of the Big M blocks restrictors to .113" which is twice the area of .080", to see what happens. I've only run it once since and noticed nothing different, but we'll see after a season of running.

 

Suprised about the lifter, its a Morel, supposed to be real good, oh well, it happens.

About the other problem, Ya, that was my fault. I had a 1/8" pipe nipple in the mix but didn't notice it was an old one from a blower boost memory kit, grabbed it by mistake. So basically the reason it seemed like there was a check valve holding the pressure was because there was. Thats been fixed.

Thanks for all the help
Corey

 

I've never tested it, but to my understanding anything over .090 is like no restrictor.

Blessings.........Ron C

 

When I was troubleshooting my lifter issue, I pulled the bad one out of its bore with the drill turning the oil pump and it was like there was nothing restricting at all. So I believe that statement Ron. I've never run restrictors and that was a huge lesson. Solid column of oil flowing through the gallery. I'm just going to leave them as is for now. I'll just have to really watch things. Accumulator is going in before the car gets run, 15 ltrs of oil in the system.

Corey