rebuild.... no oil pressure??????

stephens89sc

Registered User
rebuild.... no oil pressure?????? UPDATED!!

i just finished re-builing my motor...... i started it and it started but then i see no oil pressure and i hear the top end clickin




whats wrong???????????? i re-built everyhting to spec exaclty how it was supposed to be done
 
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Dont really know, there are so many things that could cause this.
Did you remove all lifter galley plugs after your machine work and clean out all the gunk and metal shavings from machining?
Did you clean all the main bearing oil feed holes as well?
What typ of oil pump did you use?
You did install the oil pump drive shaft didnt you?
What clearance did you set the main and rod bearings at?
You did put the right bearing halfs into the right sides of the rods and main bearing saddles didnt you?
What about the pressure reg in the timing cover?
Did you install a new one or reuse the old one?
Have you installed a mechanical oil pressure test gauge to see if you have any oil pressure at all?
As you can see there is alot of things that can cause this, But since you built the motor and we didnt it would be damn near impossable for any of us to pinpoint exactly what is wrong.
Youre pretty much going to have to check everything you have done to find the problem.
Is this your 1st engine build?
 
You need to check with a mechanical oil pressure test gauge and see if you have any oil pressure at all. You may not have any on the bottom end as well.
You didnt answer any of my qeustions in my 1st post.
I need some answers if I'm going to be able to tell you where to look.
 
ok i put a mechanical guage in and on idle i get like 2 psi when i revv it to 2000 its like 20 psi


i dont know what the hell i did wrong i fukcuing give up


all the block plugs and main bering feed holes are clean


i bought a rebuild kit for the oil pum, i installed the oil pump shaft,

i have no clue on clearance for bearings.. they are installed correctly and tourqued down to spec, i made sure the berings went on the right way, the pressure regualator was included in the re-build kit AND YA ITS NOT WOKRING SO IM GIVING UP I FEEL LIKE ****, THIS WAS SUPPOSED TO WORK NOW ITS ****ED
 
Man I feel your pain. Leave it alone for a while till you calm down.
Take off the oil filter and see if its full. If not fill it up with oil. From there I dont know what to tell you but sometimes bearing clearances will very due to production. Plasic gauge should be used at the very least to check oil clearances on bearing serfaces
I hope that all it is for your sake is the pump running dry.
Life is to short to sweat it just go back over things when all else fails.
 
ok now... im getting pressure but not enough ...... i know the berings and everyhting was put in right so im not worried about that..... the only things that im worried about are the oil pump and the oil pressure regulator now my question is.... would those cause this to happen


would they cause the pressure to still be there but not enouh of it ?
 
A lot of things again would cause no or low pressure. What is your pressure at idle? Also the oil pump housing itself can ware out as the only true way to get a new pump is to change the housing as well. The good news is that the pump is external so at least you can mess with it on the car. As far as the regulator you must insure that you reassembled it correct.
 
idel should be around 25psi....thats what i get at warm idle....cold idle is 62 and anything abover 2000rpm is 50psi when warm. It really shouldn't go past 65psi ever...its got some type of return so the presure stays at the right psi. I think its an oil pump issue, get a new pump unit from ford (94-95 style) and go from there. Sounds like the pump isn't pumping enough(worn out)
 
Wow Stephen.....Calm down buddy. I was'nt trying to set you off.
I know how it is to be where you are right now...hell I've been there myself, although I was much younger then.

Properly building an engine takes time and is realy alot of work.
You really cant approach it from the standpoint that "Well i bought new parts and bolted them together and its supposed to work"
There is much much more to it than that.
If you want to be successful at it every single part in the engine must be gone over with a fine toothed comb, old parts as well as NEW. If I had a dollar evertime I got a new part that was defective,mislabeled,misrepresented or just out and out the wrong part I would have a nice pile of cash.
While you may think the bearing clearances are right you really cant say they are because you did not measure them.
A small difference in bearing size( a difference you cannot see with your eyes) can make or break oil pressures.
When I first started rebuilding SC motors I too entertained the idea of oil pump rebuilding, infact I still have that unused rebuild kit.
After setting down and analyzing it I came to the conclusion that it really was'nt a good idea, and this is why I feel that way.
The 2 highest wear items in the system DO NOT get replaced.
The timing cover gets scuffed up by the spinning gears. The housing that the gears drop into also gets scuffed, this is important because those scuffed places reduce the amount of pressure the pump can make. The regulator bore in the timing cover also wears into an egg shape and is no longer round, so you get leakage of pressure there as well.
If you combine sloppy fitting bearings with a bad pump and timing cover that very well could be your problem.

I know you cant tell anyone what your bearing clearances are because you indicated that you did not measure them. Now dont take this the wrong way because I dont mean to hammer you about it but your inability to answer a simple engine building 101 qeustion is going to make it darn near impossable for anyone over the internet to diagnose.

You have a very serious problem on your hands and times like this really bother me:( because I'd like nothing more than to get in the truck and head over to your house and help you fix this, but I cant.:(

The only thing I can say at this point is that if that was my engine I would pull it back out and tear the bottom end back down and measure everything.
Any 1 of these things or a combo of them can cause your problem.
1. Timing cover and oil pump not up to spec.
2. Rod bearing clearances not up to spec.
3. Main bearing clearances not up to spec.
4. Oil feed holes inside the block stopped up.
5. I have even seen oil filters shut off oil pressure before. Now before everybody flogs me and says "Well the bypass valve will still allow oil to be pumped through the engine" Yes I agree its supposed to but I've seen cases on engines when it did not and oil pressure was shut completely down to the engine.
#5 is a freak accurance and I would not hold my breath thinking that was my problem.
With your oil pressure as low as it is I do not recomend starting the engine anymore because youre gonna end up ruining good parts that you may not have to replace right now.

I feel really bad for you at the moment and wish I could be more help to you, but theres not really much I can do.:( :(
 
well see my oiil pressure on idle cold is like 21psi then in a period of about 2 minutes when it got warm it dropped to almost nothing like 2psi on idle


when i revv it to about 2500rpm when its warm i get roughly 20 psi




i know that i put the motor together right, its gotta be the oil pump or the regulator but i dont understand the regulator.... how does it work and how can i figure out if thats my problem other than ripping 1/2 the motor apart to change it

im gonna try a new oil pump or another one from a friend

but what i need help with is the regulator how do i figure out if thats a problem ?
 
The best thing for you to do 1st would be replace the oil pump itself since its easy to get to.

When you rebuilt the motor what kind of shape was the machined surface of the timing cover where the oil pump mates up to?
 
OK 2 options here then:
1. Replace pump with new pump.
2. Replace timing cover.

You may get by, by not getting a new timing cover. Yours is scored I just have no way of knowing how bad. I personaly dont want any scoring in mine, but you will have to decide for yourself if you want to replace the timing cover or not.
I think they cost around $230.
Myself, I bought the timing cover as well as the pump. Thats really the only way to go about replacing the oil pump.
But on the other hand it is your money, so you will have to decide.
 
What about having a Piece of stainless steel or other hard metal Samwiched between the pump and the Timing chain cover?? only like 1/8" thick.. I know ther may be issues with the Pump drive..

But yah, that escaped me about wear marks from the Pump gears.. had that same problem at work a few times... (air cooled VW engine)
 
You know.....Thats an idea. You would only need a plate 1/16 thick to do it.
Now if you could only figure out something to repair the bypass bore you would have something.:)
 
ok well i will do that im gonna try n find a timing chain/oil pump from another sc that iknow works and bolt it on...... does a 94 timing chain cover bolt up ? cause i know someone with a full timign chain cover and oil pump laying around.... will it fit and work wiht all the other parts????



now... another thing is there any signs that id be able to see that my berings arent right or theres too much or too little clearance?

cause when the engine is running its sooooo smooth the engine doesnt move or vibrate at all its like its not even on and when i shhut it off it turns right off instantly.
 
Yah know, i have NEVER seen a 3.8's oil pump or anything first hand.. but i bet yah figuring it out wouldn't be hard...

and yah 1/16th would work too.. :)
 
ok well i will do that im gonna try n find a timing chain/oil pump from another sc that iknow works and bolt it on......

Well to be honest with you a used unit is not a good idea, it really is another unknown. You dont know for sure its GOOD.


does a 94 timing chain cover bolt up ? Yes.

will it fit and work wiht all the other parts????
Yes.

now... another thing is there any signs that id be able to see that my berings arent right or theres too much or too little clearance?
You would have to remove the crankshaft and measure the journals with a micrometer to do it right. But in this case you would be better off to use plastigauge and check them that way.

cause when the engine is running its sooooo smooth the engine doesnt move or vibrate at all its like its not even on and when i shhut it off it turns right off instantly.That doesnt mean anything. An engine with loose bearings is not going to vibrate any noticable amount. I have seen rod bearing so bad that they were just razor sharp thin copper shells and that engine didnt vibrate, But of course the rod knocked like hell. I know , your rods arent knocking but the on the bearing being .0002 too large will drop oil pressure considerbaly. Do you really think you can see .0002 with your eyes? The problem compuonds itself because youre talking about 6 rod bearings and 4 main bearings thats 10 bearings. If there off by .0002 each then you got one helluva pressure leak. Do you understand what I'm saying?
 
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