oil pressure problem

[20blackone00]

ok so this is my 3rd motor...second motor with oil pressure problems. Some might remember the first one that didnt have any oil pressure at all but anyways this motor is now having problems. Bascially on a cold start up the oil pressure is around 75 psi never goes any higher, once it starts warming up it slowly drops down and when finally warm its a little below 20 psi on the gauge and sometimes jumps around from like 18 to 25...cruising it is right below 50 probably about 45 but when u put ur foot into it it will go anywhere from 40 to 60 psi...never any higher...

i know thats not a lot of information but if anyone knows what it might be that would be a great help. we have tried 3 different gauges too so that rules out that...and different sending unit. I cant imagine 2 pumps being bad, but i have no idea what else would cause this?

thanks guys!

 

[20blackone00]

Ttt

 

[chip moore]

What brand and thickness do you use?

 

[20blackone00]

Royal purple and its 5-20

 

[20blackone00]

Royal purple and its 5-20

 

[20blackone00]

Royal purple and its 5-20

 

[chip moore]

Hmm. That's pretty thin I think??? I run 15w40 Rotella! In all my vehicles. Love it. But I don't have an oil psi gauge.

 

[lightninmike]

well 15-40 i dont think is a good idea in these motors maybe try to bump up to 10-30. i know when i warm my truck up i am right up at 100 psi and cruising i am at 75 psi.

 

[Taunto]

i use amsoil 5-20 and its all good. what u can try doing is take your valve covers off, the whole front cover, oil pan and oil pump. once the oil pump is off slide a blow gun into the oil gallery with a rag over the end so u dont get oil blowing back at u. then blow air through it. I just re-built a 5.7 hemi at work and was having no oil pressure and found that it was leaking through the rocker shafts. maybe ur cam journals are leaking who knows. also u can hook a oil pressure guage up to the it. then un-hook the starer selonid connection and jump the stater so it will free spin with out actually running the engine. the engine may only be turning at 200rpms but u should see at least 20-30psi.

Hope this helps

 

[Robert Francis]

Oil psi readings depend upon a lot of things. In additon to the mechanical clearances in the engine, a lot of psi readings depends upon gauge accuracy. Your readings may be ok for your engine.

I have a mechanical guage I installed on my V6 Ranger and at a cold start (60 degrees now) at about 1100-1200 rpm, reads about 60-65 psi. When fully warmed up, and idle speed about 650 rpm, reads about 20-25 psi. When I accelerate fully warmed up, the oil psi immediately raises with rpm to a max of about 55-60 psi. I've had big V8's never top 70 psi. When driving about about 25-30 mph, psi is about 40-45 psi. Rises and falls like this, like what you have, is common.

 

[20blackone00]

while going WOT it goes from 40 to 60...thats not normal..at idle (warm) its at 20 psi if not a little lower and sometimes jumps a little above 20...while giving it more gas it should go up not down...

i talked to rick and houston performance (LFP's builders) and they both have thought it might be the pick up tube being blocked or it being lose...

 

[20blackone00]

ttt

 

[chip moore]

get it fixed?

 

[20blackone00]

Not yet...we plan on taking the motor out this weekend

 

[uncooked]

I switched from 5-20 RP to 5-30 RP from others advise on here. Picked up 5 - 10 pounds on my gauge. Apparently these motors are designed to be used with 5-30, 5-20 was just for some emissions crap.

25 - 30 pounds hot in gear sitting at a light, about 60 lightly cruising around. then probably around 80 - 90 or so at wot.

 

[uncooked]

You are 100 % sure the gauge / sender are working normally ?

 

[Taunto]

your gonna pull the motor when it can be something as simple as a pick-up tube? heck pull the pan and pick up tube offf first, clean it real good clean the pan real good then put it back together put some oil in it, and start it up, see how it is. might save u alot of time and hassel.

 

[20blackone00]

your gonna pull the motor when it can be something as simple as a pick-up tube? heck pull the pan and pick up tube offf first, clean it real good clean the pan real good then put it back together put some oil in it, and start it up, see how it is. might save u alot of time and hassel.

doesnt the motor have to be pulled up a little to get to the pick up tube and stuff? we were going to lift the motor up and pull the pan first then if we had to we were going to pull it...

what would u guys suggest to do first?

 

[Silver '01 L]

Pick up the motor and drop the pan to clean the oil pickup.
Mine did the same thing and it was the pickup becoming blocked.

 

[20blackone00]

Pick up the motor and drop the pan to clean the oil pickup.
Mine did the same thing and it was the pickup becoming blocked.

ok man...thanks!!

i really hope thats all it is!! did u just replace it or clean it? i think i might just replace it?