Moparts
no oil pressure on first start up
Posted By: 72dak
no oil pressure on first start up - 11/16/08 12:26 AM
i have a 72 340 that was freshly built and running for a short time before i got it, but mice got in it and filled the intake with corn, so i tore it back down, cleaned everything and put it back together. i got it running again and im not getting oil pressure at idle and only about 20psi when its revved up a little. i prelubed it with a drill once before and i got about 20 psi. the engine is now in my 94 dakota and the oil pan is very hard to remove. im looking for any advise for things to check without pulling the pan. any help would be great
Posted By: Posest
Re: no oil pressure on first start up - 11/16/08 12:39 AM
Much as you dont want to hear it, you have to pull the pan. I went through the same thing with a 360 I bought. With the pan off I found a half a dozen dead mice in the bottom and a few in the pick up tube screen. Previous owner had drained the oil and left it empty. The mice made a cemetery there. Is your Dakota a engine swap, if so it should not be to hard to just pull the whole engine. My 90 engine swap was pretty easy and I plan on doing it again once I get an oil pan for my 408.
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 12:53 AM
i took the engine all the way down pistons,heads,oil pan and all. it should be completely clean as far as that goes. its a new pickup and its been sealed up tight since i put it back together so mice couldnt get in again. it just wouldnt make any pressure so i changed guages and it didnt change.theres no leaks externally and the engine sounds fine. im at a loss
Posted By: ademon
Re: no oil pressure on first start up - 11/16/08 01:14 AM
is the plug installed behind the cam plate?
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 01:20 AM
it should be i dont know why i would have had to remove it
Posted By: sbhpcb
Re: no oil pressure on first start up - 11/16/08 01:48 AM
I bought a motor that the plug had been left out of. I found it when I primed the motor, Oil poured on to the distbutor gear location when I turned the oil pump.
Posted By: AARCONV
Re: no oil pressure on first start up - 11/16/08 01:53 AM
when u said running for a short time...how short was that and did it have oil pressure then?...
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 01:58 AM
it was in a car for about a year and i would assume it had oil pressure. the guy who had it built it right and had alot of cash in it i dont see why he would run it without oil pressure
Posted By: CrAzYMoPaRGuY
Re: no oil pressure on first start up - 11/16/08 02:06 AM
Do you have a remote oil filter?
It sounds like a vehicle with crossed remote oil filter lines to me..??
If no remote filter and the valley end plugs are in it's a tough guess..
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 02:10 AM
theres no remote filter i just have a 90 degree adapter
Posted By: CrAzYMoPaRGuY
Re: no oil pressure on first start up - 11/16/08 02:14 AM
Did you check the oil pickup screen?
Sorry, but I ain't up to speed on your situation yet!
Posted By: CrAzYMoPaRGuY
Re: no oil pressure on first start up - 11/16/08 02:16 AM
Have you tried an independant mechanical gauge into the back of the block?
Have you tried priming it with a priming tool with an independant mechanical gauge?
Posted By: RapidRobert
Re: no oil pressure on first start up - 11/16/08 02:24 AM
yes a tough one. you might pull the dist/intermediate shaft/oil filter & spin the pump(CW) w a priming shaft & see how much flow you have at the 90 degree adapter as you spin the drill at varying speeds which would let you see whats up at the beginning of the pressure side. If good I'd pull the intake & prime it again & see what you see.
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 02:24 AM
yeah the pickup is brand new. it never ran with the mouse nest in it, but i decided to tare it all the way down anyway to make sure i wouldnt have problems. all i did was pull the intake, heads and pistons, cleaned them and put it back together
Posted By: rhad
Re: no oil pressure on first start up - 11/16/08 02:29 AM
maybe the pressure relief valve is stuck open?,it happened to me on a ford and also on a chevy
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 02:31 AM
all i had was a mechanical guage, so i tried another one and i still had no pressure. i took the whole setup and hooked it up to my old worn out 318 van and i was getting almost 40 psi at idle, but it was cold. either way my mechanical guages are obviously fine.
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 02:33 AM
is the pressure relief right in the pump?
Posted By: stumpy
Re: no oil pressure on first start up - 11/16/08 02:36 AM
What did the bearings look like when you pulled the pistons? Did you pull any mains to see what they looked like?
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 02:42 AM
i looked at all the bearings since it was apart and they all looked good. overall every part i took out looked almost new, but i didnt actually pull the cam or crank
Posted By: rhad
Re: no oil pressure on first start up - 11/16/08 04:30 AM
once i had a reman chevy that seemed to have pressure when you used a drill to prime the pump,but it wouldnt show any on the gauge,turns out there is a small soft plug that fits in the oil galley that directs oil thru the filter,the plug was out of place as in pushed up to far ,and the oil would go thru the filter but wouldnt get to the bearings or the gauge,does dodge have a similar setup??,seems like they might
Posted By: dustpan man
Re: no oil pressure on first start up - 11/16/08 04:39 AM
try a thicker oil if it still does it change the pump if not leve it alone try 15 40 it mite just work
Posted By: runinonmt
Re: no oil pressure on first start up - 11/16/08 10:15 AM
Don't just look at the bearings - check them. Brother in law had a 383 with a turned crank and std. size bearings. 20 Psi oil press. Guy that built it never even Plastigaged them. What you assume to be right is what will come back to bite you.
Ron
Posted By: 4BBodies
Re: no oil pressure on first start up - 11/16/08 12:57 PM
I bought an Olds 350 once that was "rebuilt," and it had low oil pressure. The bearings were new, as are yours, but upon further examination I found a new rod bearing on a wiped rod journal, with ohhhhhhh, what was it............ .030 clearance?! The oil must have been pouring through there........and it was just starting to knock........might not be what's wrong with yours, but I have learned to be very leary with previously "rebuilt" engines. Just my
Posted By: CrAzYMoPaRGuY
Re: no oil pressure on first start up - 11/16/08 06:36 PM
Does oil get to the top (rockers)?
When the engine was running was there loud lifter noise?
Posted By: 72dak
Re: no oil pressure on first start up - 11/16/08 09:33 PM
i took the right valve cover off to see what i had at idle and i didnt see any oil flow, the engine never knocks or makes any strange noise at all. i hit the throttle up to about 1000 rpm and oil sprayed everywhere
Posted By: 69Cuda340S
Re: no oil pressure on first start up - 11/17/08 03:39 AM
Pull the distributor and look forward to see if the rear lifter oil gallery plug is in place.
Posted By: 540challenger
Re: no oil pressure on first start up - 11/17/08 04:32 AM
Quote:
i took the right valve cover off to see what i had at idle and i didnt see any oil flow, the engine never knocks or makes any strange noise at all. i hit the throttle up to about 1000 rpm and oil sprayed everywhere
Might want to double check the pickup you installed. If it was to close to the bottom of the pan that might happens. Assuming it had oilpressure before the tear doing i would think the pick-up might be the problem
Posted By: RapidRobert
Re: no oil pressure on first start up - 11/17/08 03:54 PM
If you R&R the pan you might throw another pump in there. It might be as simple as the regulator sticking/sluggish from a little piece of crud. Do let us know what it ends up being. Inquiring minds want to know
Posted By: 72dak
Re: no oil pressure on first start up - 01/26/09 07:01 AM
hey guys i know its been a while, but as you could imagine this time of year in wisconsin makes it hard to work in a garage thats not heated/insulated but i finally got my oil pan off which involved pulling the engine and pretty much all of your suggestions were right, the relief on the old pump was stuck wide open, even though it was fine when i installed it. i threw a new pump in, put the engine back in and once i started it up i was getting about 40 psi at idle. its a real relief to finally be able to drive this thing after how much time i put in it, so thanks for all of the suggestions and if i have any more problems ill be sure to come back here
Posted By: bigblock4x4
Re: no oil pressure on first start up - 01/26/09 10:18 PM
on my first rebuild of a mopar i was used too chevys.I installed the rocker arm shafts with the oiling holes pointing up(that wasnt right)my oil pressure in my 440 was the same way.now i know thats not how the rocker arm shafts go after i gaulded some nice rocker arms and shafts.thought i would throw that out there.they are for drivers side and passenger side,guess i should have read my chiltons a little closer.