Quote:

---

So some of you might rememeber my lengthy thread from not too long ago about my very low oil pressure issue. I ended up tubing my block as per the mopar performance manual, got it all cleaned up and assembled and went to go prime the engine on the stand today. The only changes I made were- tubing the block, removing the restrictors I installed feeding the rocker shafts in the Indy heads, and removing the high pressure spring from my high volume pump and re-installing the standard pressure spring.

Using a quite weak air powered drill, pressure pegged the 100 psi on the gauge instantly, with little to no drop at all. Oil is getting to the heads and draining back sufficiently. I am thinking that possibly now with the lifter gallery tubed the oil pressure is much higher since there is less area for oil to bleed out/fill in.

Has anybody had this issue before? I am certain the cup plug was installed the correct way on the oil pump. At this point I am going to try installing the standard volume pump, but just wondering if this is normal after tubing the block and if it could be something else I have looked over?

---

Quote:

---

If the bypass is being stuck open, is that something I can check for when removing the pump? How can I see if that was the problem- pull the cup for the bypass spring out and the spring and take a looksie?

Other then running the engine on an engine stand (And it is not totally buttoned up yet), how would I be able to see what the hot oil does? I have had 70 psi cold before in other motors, but never 100. That just seems way too high cold, even with 10w30wt oil like I used to prime it.

And yes, it did end up being the lifters that were causing my pressure loss. I still kept the intake off when I was priming just to watch drainback from the heads and to see if the mod worked in blocking the oil from the lifters. The cam bearings at #2 and #4 are draining losing oil, but it must be normal and I just did not know what to expect when watching oil coming from the full groove cam journals since the oil pressure is now quite high.

---

IF its stuck its stuck CLOSED.. otherwise you would
be in the 70# range(the by-pass would open around 70#)
and dump the excess oil back... yes the 2 and 4 will
have oil dumping from them but its a matter of how
much and thats really hard to say whats normal if you
cant run that through a flow meter.. but like you I
still feel the lifters are/were the major leak and
on my engine with bushed bores and the .062 hole in
each one is still a major leak with the EDM hole on
the lifters and PR oiling on mine and the loss around
the lifters
EDIT
what weight oil are you running and you could put
a few qts of 5 weight in to simulate hot oil(just
enough to prime the system)

Quote:

---

At this point I am going to try installing the standard volume pump, but just wondering if this is normal after tubing the block and if it could be something else I have looked over?

---

Quote:

---

Not unusual for melling hv pumps to give too much pressure.
Think ive had 2 or more of them.

---

Pretty sure I have a like new one (high volume) still laying under my work bench that was putting out over 130 pounds of pressure during a 1/4 mile pass. Thank God I didn't have a Fram oil filter on my Duster.

Quote:

---

Yep..

---

Thankfully it was an easy fix and I did it on the stand instead of fighting with it all in the car.