Low oil pressure on new engine install

[searcherrr]

I decided to make a simplifed thread here to tackle some ideas on this problem.

1995 3.8L just installed new remanned engine from truetestengines.com (aka ATK).... supposedly a GREAT company.

Main issue: Oil pressure (and/or level) light flickering after moderate driving for 30 minutes. Only flickers at stops in Drive or in Park. Oil level is ABOVE full mark on stick.

Engine came with new oil pump.

Engine has new oil pressure sending unit.

The shop manually installed oil pickup (which I suppose is the same as saying "screen")

Battery sat for 3 weeks not started and I don't know if they disconnected it while they had the engine out.

Alternator pulley's known for going bad on our vans (addressing a churping issue that SHOULD BE separate from this), but alternator has always been working fine and checked good a few months ago though maybe they messed it up during engine install?

Main questions are:

What is the most likely culprit to cause low oil pressure on a brand new engine installation given what I've said above?

What could the SHOP have messed up that would cause low oil pressure during this engine installation?

Could the screen have been installed WRONG some kind of way to restrict oil flow?

Are the oil pump and pressure relief valve together or physically separate and just COME together in one package?

Can the oil pump be installed right but the pressure relief valve wrong such to cause low oil pressure?

Can alternator or battery going bad cause low oil pressure light to flicker?

Could the camshaft position sensor synchronizer shaft be "out of whack" somehow causing low oil pressure?


Grasping at straws here cause while it is back at the shop again as of yesterday I want to be able to keep abreast possibilities myself such to helhp the shop work faster especially since it looks like they are now going to have to involve TrueTest (ATK) for AFTER install repair work.

[12Ounce]

I've taken an image of a '99 front cover complete with oil pump. I have marked the pressure relief valve area with an "X". You can see it belongs to the cover, not the pump. Below the metal cover/cap is a spring and a valve (ball?). I have just begun to clean this cover. Before reusing I will open and inspect the pump and the relief valve. Aftermarket pumps, complete with relief valves, are available.
.

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[garync1]

You will need to get a gauge reading to make sure low pressure is the problem..It could be as simple as a bad ground to the oil light sender. But I would check into making sure that the oil pressure is really low. Also don't take no chances until then. Take back to the place and make sure they verify the oil pressure..

[CnlK]

I assume your 95 3.8L would be similar to my 2000 3.8L The driven gear
on the camshaft synchronizer drives the synchronizer vane that triggers
the sensor and also drives a shaft that rotates the oil pump. Just a thought,
if the flats on the shaft are worn or the gears are bad there could be some
slippage. These materials are hardened so that seems remote. This sounds simple, but I have seen the wrong oil filters installed on engines, something easy to check. A gauge reading after checking on the oil filter
would be the way to start.

The only oil pressure spec in my Haynes manual for years 1995-1998 3.8L engine hot
at 2500 rpm 40-60 psi. Pressure at idle is not addressed. If the oil level was significantly
above the full mark, the possiblility of the oil foaming and entrapping air would exist. This
could therotically lead to low pressure.

[wiswind]

This is something that I would have the shop address.
They can check the battery to see if it is at the correct charge, clean connections (including ground to the chasis and engine), etc.

There have been posts about the oil pickup / strainer getting clogged with junk and causing low oil pressure....but that would be unlikely with your new engine.
I would expect that the shop would have eyeballed it before installing it to make sure that it was clear.

On my '96, it is normal for the oil level to be slightly over the crosshatch area on the dipstick....with 5 quarts and a filter change.
That is OK up to the bottom letter in the FULL lettering.
Any higher would be not so good.

[searcherrr]

Originally Posted by wiswind

This is something that I would have the shop address.
They can check the battery to see if it is at the correct charge, clean connections (including ground to the chasis and engine), etc.

There have been posts about the oil pickup / strainer getting clogged with junk and causing low oil pressure....but that would be unlikely with your new engine.
I would expect that the shop would have eyeballed it before installing it to make sure that it was clear.

On my '96, it is normal for the oil level to be slightly over the crosshatch area on the dipstick....with 5 quarts and a filter change.
That is OK up to the bottom letter in the FULL lettering.
Any higher would be not so good.

Thanks to all who've responded.... does ANYONE know what the oil pressure should be at idle and during driving? I have seen various posts all over about checking this, but NO ONE specifies a pressure range that is valid. ANYBODY?

Don't worry its at the shop, but I'm not content with letting them work out their own possibilities list as while they do actually do great work at the same time they don't seem to be able think of everything that a problem "could be".

They did test it and remarked it seemed LOW on the oil pressure, but wanted to verify the right pressure range themselves TODAY and were supposed to call me answering ALL of my questions I put on my list to them, but they didn't call me ONCE.

Wiswind - I suspect the oil passages of course should've been completely clear too and that this is a lesser possibilitiy than the oil pump being bad, battery, alternator, grounds etc... I'm dropping off a list of these things for them to look into for tomorrow and for them to check the battery and alternator conditions.

I registered the engine's warranty before the shop opened this morning so hopefully if the shop called the manufacturer its all in order with the paperwork.

Wiswind - I put on a new ground cable from the ALT to the frame a while back and when I did I noticed just EVER so slightly that the width of the cable end point which surrounds the bolt at the ALT was a MAYBE a tad wide causing possibly 1mm of space between the fastened cable end and the metal on the alternator itself. I shined a light from behind it to verify this space was there, but I gave it my MOST strength to tighten it as tight as it would go and surrounded the edge of the cable end to ALT metal with silicone thereafter to prevent moisture from getting in there if there was any small space (however so slight) left after I gave it all my man power. I know they disturbed this wire when they took the engine out because there is a NEW bolt there cause I think the old one was striped inside its seat and I swear the alternator arm that bolt is in looked ever so slightly BENT though the PULLEY still looks LEVEL as can be..... BUT I also have a new CHURP from the pulley system since they did all this work so MAYBE its that?

EDIT: Forgot to mention. I'm pretty damn sure the OIL was ABOVE the "F" on the stick.

[wiswind]

I tried looking for a oil pressure specification on Alldata, but did not find one.
The pressure sensor is behind the power steering/alternator bracket.
I have it shown in one of my pictures, with the power steering bracket removed.

Alldata says that the oil pressure light may flicker slightly when the engine is at idle, but will go out with the engine at above idle rpms.
I seem to think that this is VERY rare......as I am sure that we would have a number of posts coming up all the time about a flickering oil pressure light.
I know that if I had that.....I would be installing a actual gauge, and I'll bet a few of the other regulars here would be doing the same.

The pressure regulator in 12Ounce's picture is replaced by drilling out a corresponding "plug" in the front cover (aka timing cover) and removing the regulator......put the new regulator in and install a new plug.
That is the process to change it with the cover installed on the vehicle.
I have no idea of how difficult that would actually be......how much stuff is in the way, etc.
Again......you may find something with a search on oil pressure, but failure of the regulator would again not be common....or there would be more posts.
Of course, in your case, I would NOT attempt the repair, as that is part of the new engine replacement warranty responsibility.
I still am of the thought, like your shop is, that the oil pressure is truely low, but as to why.....I don't know.
But, again, that is not your responsibility.....other than to get the vehicle back to the installing shop to have the issue addressed between them and the company that supplied the motor.

[12Ounce]

Replacement of the regulator is not something to be done with the cover installed. It easy enough to pluck out the regulator with a small bent-bar tool, if the front cover is removed as shown in photo. There is space ( a slot of sorts) along side the body of the regulator for this operation.

[garync1]

It not rare at all for an issue from a reman engine to come up. I helped a guy with his 1998 blazer when the engine came with a bad seal on his timing cover. That was a pain in the butt. Have to drop oil pan to get to it. Plus the engine came with a oil pan for a 4 wheel drive so it was deeper than the one with out 4 wheel drive. So that meant dropping engine mounts and jacking up motor. If they had the right oil pan that came with it. All would needed to be done is to drop oil pan. So they can have issues sometime. Sorry for your troubles though..

[wiswind]

I too found it unusual that they would have the pressure regulator replacement instructions having you drill.
Removing the front cover is a MAJOR job as well.
In Searcherr's case, the repair would fall well within the responsibility of the supplier of the engine.

[12Ounce]

Well, actually drilling the sheet metal cap and then plucking it out with a punch or the like is a workable plan ... its just that drill chips make me uneasy, especially if they aren't necessary.

Considering the importance of this little spring ... I wouldn't wonder that it's failure has led to the failure of many engines. All it would take is one little crack.....

Yes, removing the front cover is a major job! You are well on the way to total engine dismantlement when it is done.

[tripletdaddy]

Is the metal plug visible in the 12ounce pix, I couldn't find it? I assume it is on the other side of the cover. I was going to suggest without seeing it, that instead of drilling a "pilot" hole into the plug, but instead poke a hole into it with a very sharp and fine punch, resulting with no "chips" going inside. Thoughts?

[12Ounce]

The white "X" is directly on the sheet metal plug ... maybe I didn't make it big enough? Click on the photo to enlarge.

When I get a free minute, I'll pluck it out and take another photo.

[searcherrr]

Originally Posted by garync1

It not rare at all for an issue from a reman engine to come up. I helped a guy with his 1998 blazer when the engine came with a bad seal on his timing cover. That was a pain in the butt. Have to drop oil pan to get to it. Plus the engine came with a oil pan for a 4 wheel drive so it was deeper than the one with out 4 wheel drive. So that meant dropping engine mounts and jacking up motor. If they had the right oil pan that came with it. All would needed to be done is to drop oil pan. So they can have issues sometime. Sorry for your troubles though..

I would not have known that its NOT rare for a reman engine to have issues. I mean all the touting these remanner's do especially ATK or Jasper you'd think that it would just be like new as I thought it would be. I mean why would I even have to THINK about a regulator, oil pump, pressure relief, etc... after spending all that cash. Now its their f'in fault I probably have to wait another 2 weeks to get my damn van back. In the end it'll probably amount to 2 MONTHS out of commission. I'm just damn lucky I am in the situation i'm in right now to where I don't need transportation at the moment cause I can borrow my parent's vehicles or use my 2nd broke vehicle if I feel like finishing up repairs. LOL

On the note of what ya'll are talking about.... yeah its retarded to have to drill out ANYTHING on the vehicle to replace it. I don't quite understand the design thoughts behind such a thing.

Status on my van: After this ENTIRE week of waiting and after the guy having told me from the shop he'd call me the VERY NEXT morning with ALL my answers to ALL my questions (said this 4 times) I have STILL not had 1 single phone call from them. I can attest this to my belief that they are extremely embarrassed and PISSED off at the same time. They basically don't want to talk to me till they have answers or it all taken care of is the usual jest I get from them. But dammit I want an UPDATE without having to beg for 1.... especially if I'm going to have to PAY DOLLAR ONE FURTHER out of pocket.

[tripletdaddy]

I was refering to the "plug" that Wiswind was saying gets drilled out while the timing cover is still installed, which I now realize sounds like a new hole you have to make for the regulator repair. So my suggestion would not work if that is the case and drill chips doesn't sound good to me either, steel, aluminum, anything or even getting to it like Wiswind said. That is why I was refering to the outside of the cover, not the inside as 12ounce had marked the plug over the pressure regulator. Does that clear the mud?