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bowez
09-05-2009, 03:28 PM
Just primed and checked my oil pressure before the engine goes in and got 75PSI (using a 18V BD drill), is this ok or may the rod be too tight, I check all the main and they were .001 to .0015 (by plastigage), rods were .001 or less real hard too tell.

CMac89
09-05-2009, 04:54 PM
I wouldn't go by Plastigage, but those clearances are tighter than what i like. Anyways, you will get full oil pressure off of a drill. It only takes a couple hundred RPMs to run an oil pump at a pressure to engage the relief valve.

bowez
09-05-2009, 04:58 PM
So am I ok, or is do I need to try the STD rod bearings? It is the clear that STD mains are a no go.

Running 10W-30 and just remember there was a kink in the mechanical gauge was using (Sunpro)

bowez
09-05-2009, 07:27 PM
Is not the kink in the gauge line, just removed it and still 75PSI.

Is there any problem with pressure that high?
What is most likely to cause it, Relief valve to far in, or bearing clearances too tight?

bowez
09-06-2009, 07:30 PM
All clearances are .001-.0015. Am I right to assume the issue is in the relief valve being too far in or pump to tight?

If bearings clearances are good can I just ignore it and take it as my new normal?

Duffy Floyd
09-06-2009, 08:51 PM
I would not. Ken Seegars blew a couple of oil filters up ignoring high oil pressure issue.

bowez
09-06-2009, 10:04 PM
Solution then?

Duffy Floyd
09-06-2009, 10:18 PM
Contact Ken and ask him how he solved the issue. He was thinking it was the relief valve inserted too far but I don't remember if he actually found that was the case.

XR7 Dave
09-06-2009, 11:13 PM
75psi is entirely normal.

Duffy Floyd
09-06-2009, 11:24 PM
Spinning the oil pump with a drill????? Sounds high to me but David is the expert.

pearl95sc
09-06-2009, 11:51 PM
I get 70-80 cold, depending on temp, and 60 at cruising speeds, 30-40 idle.

Like dalke says, sounds normal to me.

Duffy Floyd
09-06-2009, 11:56 PM
Yeah you might with the engine idling at 900 RPM but my understanding is he hasn't even started the engine yet and is only using a drill to prime the oil pump.

pearl95sc
09-07-2009, 12:23 AM
Keeping in mind, the speed that drill is workin the pump at will also dictate the pressure. If its a plug in drill at full throttle, 1200-1600rpm, that will show a tall number.

bowez
09-07-2009, 08:40 AM
18V B&D Cordless and then engine is still on the stand. 80 degree ambient temperature.

XR7 Dave
09-07-2009, 08:53 AM
Yeah you might with the engine idling at 900 RPM but my understanding is he hasn't even started the engine yet and is only using a drill to prime the oil pump. Engine rpm at idle x 50% = dist rpm at idle. Therefore base idle oil pump rpm is about 300-450rpm. All drills even on low speed would probably exceed that rpm.

My bone stock, all original, unmodified, unrebuilt SC engine with stock m137 oil pump and 10w30 oil idles at 75psi on startup and maintains that until fully warm at which point I generally see 45-50psi. Granted I run that motor cool (rarely over 180 deg).

Many of my rebuilt performance motors generate 90-100psi on startup because the aftermarket relief valve springs seem to be a little stiffer than stock. Ken Seegers was pegging his 100psi oil gauge IIRCC.

Ira R.
09-07-2009, 10:49 AM
Engine rpm at idle x 50% = dist rpm at idle. Therefore base idle oil pump rpm is about 300-450rpm. All drills even on low speed would probably exceed that rpm.

My bone stock, all original, unmodified, unrebuilt SC engine with stock m137 oil pump and 10w30 oil idles at 75psi on startup and maintains that until fully warm at which point I generally see 45-50psi. Granted I run that motor cool (rarely over 180 deg).

Many of my rebuilt performance motors generate 90-100psi on startup because the aftermarket relief valve springs seem to be a little stiffer than stock. Ken Seegers was pegging his 100psi oil gauge IIRCC.

100 on cold start. Heats up to run at 80 and generally hot idles at 40ish.

Ira

David Neibert
09-08-2009, 12:02 AM
Spinning the oil pump with a drill????? Sounds high to me but David is the expert.

Duffy,

We got 90 psi on my new 4.3 motor with an electric drill. In the car cold starts were showing about 95 psi.

David

slowpoke
09-08-2009, 12:54 AM
mine shows 100 on start up and average 75 at operating temp.

Ken Seegers
09-08-2009, 12:50 PM
I was pegging my oil pressure gauge @ 100+ psi. It was due to the cap on the pressure relief valve in pushed too far in. I am talking 1/4". This was on my 92 which I had the motor rebuilt by someone else. I also picked up a 93 SC with the same problem. I am running 75 at cold idle with 5/30 oil. I am at 60-75 at hot running 2k - 2.5k. My engine runs at 210* I haven't had any problems since then.