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I have a 68 F250 that I recently swapped the 240 out for a 300 six from a 75 truck. I put a new oil pump on it. I primed the oil pump with a distributor shaft that I took off a old distributor and with a drill, and it got oil pressure.
The problem I'm facing is that the front rockers are getting tons of oil, yet the back 4 rockers are getting little to no oil. I took the pushrods out and blew thru them and ran a piece of welding wire thru them, re-assembled, same thing. I took the lifters out and attempted to clean them, (honestly, I don't really know a proper way) and still nothing. I swapped a pushrod from the front lifter which gets tons of oil to the back, and still no oil. (Don't worry, im not switching up lifters)
I'm running 1540 oil in it and a motocraft filter. I'm at a loss, I'm familiar with FE oiling systems but not the 300s.
In the 240/300 oiling system the oil travels from the filter to an oil passage that feeds the lifters first then offshoots go to the cam and main bearings.
Are you using a really strong 1/2-inch drill to turn the pump. If not, you may not be getting enough oil pressure built up. Are you imprint certain you have a good engine?
In the 240/300 oiling system the oil travels from the filter to an oil passage that feeds the lifters first then offshoots go to the cam and main bearings.
Are you using a really strong 1/2-inch drill to turn the pump. If not, you may not be getting enough oil pressure built up. Are you imprint certain you have a good engine?
when I primed the oil pump with a drill it certainly got oil pressure, didnt hook it up to a gauge but I could feel it in the drill. Shot out the oil sensor port. The truck runs and will dump oil with the front rockers but the back gets almost none.
If it runs you need to hook up an oil pressure gauge and see what you have. It is possible but highly unlikely you have more than one lifter not oiling. If the lifters are not making noise, then they are getting oil. Did you make sure the oil holes in the rockers are open?
If you find you have good oil pressure and need to take a lifter apart this is what is in there. The one on the left is a type 1 the one on the right is a type two. The easiest way is to use a drill press with an old pushrod or piece of round rod. Press down on the cup until the plunger moves down enough to remove the snap ring. the pushrod cup and metering plate will fall out. If the plunger will not come out apply some compressed air into the center of the plunger, a little is plenty you don't want to shoot it across the room. You do not need to remove the check valve on the bottom of the plunger. Clean them with an old toothbrush and some solvent. Dip them in some oil and reassemble unless there is something wrong with them. DO not mix parts they are matched.
I have found when priming the oil and to get oil to all the rockers I needed to turn the motor over.
I build pressure then turn the motor 1/4 turn and build PSI again then 1/4 turn, build PSI again, turn the motor over etc and make 2 full turns.
What I believe happens is the lifter bore oiling and the lifter oiling holes dont line up and why no oil to the lifters, push rods & rockers.
Now that may only be with high lift cams that I have run in v8 motors but the last one was a big street cam so not that high of a lift.
Dave ----
I have found when priming the oil and to get oil to all the rockers I needed to turn the motor over.
I build pressure then turn the motor 1/4 turn and build PSI again then 1/4 turn, build PSI again, turn the motor over etc and make 2 full turns.
What I believe happens is the lifter bore oiling and the lifter oiling holes dont line up and why no oil to the lifters, push rods & rockers.
Now that may only be with high lift cams that I have run in v8 motors but the last one was a big street cam so not that high of a lift.
Dave ----
I'll try pulling the distributor and priming it and turning it. It doesnt get oil back there while running so not sure what its going to change
I missed you had it running
I think I would pop the side cover off and pull the lifters for the ones not getting oil and prime again and look down into the lifter holes to see if oil is making it back there.
You may need to put a lifter in to get oil out the one next to it and so forth.
If you are getting oil to the lifter holes then move to the lifter and then push rods etc.
Dave ----
I read something a while back concerning Melling replacement rocker arms. The oiling hole in the pushrod cup was improperly placed, effectively cutting oil off to the rocker pivot. The pushrod end would oil, but it would "deadhead" there and not oil the rocker pivot.
One thing you could do would be to swap rockers around to see if the problem followed the rockers. It does, then look at the relationship of the oiling hole in the rockers and the end of the pushrod.
Are all of the rocker arms moving? It could be possible that the engine was over revved and tossed out a lifer. That would stop the oil flow to all of the ones that are farther down the galley.
