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James Hall #1
10-19-2012, 04:42 PM
I have a 2.3 ford race motor. When I start it up cold, it has 35 pds of oil pressure and continueously drop as the engine warms to 20 pds. The last race its had fallen to 10 pds as I came off the track. I can't get to race this car because of this problem. I've had this engine apart 3 times this summer. I have installed a new oil pressure gage and oil line. I have changed rod bearings and mains 2 times. I put in a new crankshaft with matching bearing and plastic gaged them with .03 clearence. I've had 2 new high volume melling oil pumps in, and went as far as to shim the spring in one of them. I took the alluminum Essy Head and had it aline bored and new cam bearings installed. I have changed engine blocks and all oil ports have cleaned and all oil plugs put back in. I have no oil in the water or any oil leaks to the outside of the engine. Why can't I get oil presure ? Please, anyone,,lol

raabbiitt
10-19-2012, 05:04 PM
bolt another head on it, even an old iron one off a junker and see what pressure you have, that will eliminate any issues at that end. if the pressure is the same, it's not the top end, high pressure means the problem is in the essy head

James Hall #1
10-19-2012, 05:12 PM
I thought of that,,, last resort I guess ,,,, thanks for replying

1195
10-20-2012, 11:56 PM
Have you checked the oil pump pick up tube for cracks?

James Hall #1
10-22-2012, 03:06 AM
Did that, last time apart. Seems to me like it would have to be the head having a crack with oil leaking back into the valve area on top. And it should be gushing to loose that kind of pressure, should be able to see it.

1195
10-23-2012, 11:19 PM
Take a old distributor remove the gear install in the engine. spin it with a drill look for leaks with the valve cover off. You will need to cover the oil holes on the cam lobes or you will have oil everywhere.

Headhunter
10-24-2012, 11:23 AM
What oil pan do you have on it? I have run into a issue with a bad designed aftermarket pan and high oil temperature causing low oil pressure.

James Hall #1
10-24-2012, 08:34 PM
Take a old distributor remove the gear install in the engine. spin it with a drill look for leaks with the valve cover off. You will need to cover the oil holes on the cam lobes or you will have oil everywhere.

I'm going to do this,,, thanks

James Hall #1
10-24-2012, 08:37 PM
What oil pan do you have on it? I have run into a issue with a bad designed aftermarket pan and high oil temperature causing low oil pressure.

I'm not for sure what brand it is but its a 7 qt. pan with a trap door in it. Oil pressure low before it warms. I'm thinking it should run at least 65 pds cold and no less than 40 hot.

Headhunter
10-26-2012, 12:12 PM
You may want to make sure you have at least 1/4 to 3/8 of a inch clearance to the picup from the bottom of the pan. If all else checks out like bearing clearances and the rest you may be sucking the pickup to the bottom of the pan..

James Hall #1
10-26-2012, 06:45 PM
You may want to make sure you have at least 1/4 to 3/8 of a inch clearance to the picup from the bottom of the pan. If all else checks out like bearing clearances and the rest you may be sucking the pickup to the bottom of the pan..

Good idea, maybe, I've only got run it twice this summer because of this problem, tomorrow night is the last race, :(

James Hall #1
07-08-2013, 08:21 PM
Still have this same problem,,,,no oil pressure,,,, had the head sealed up and pressure checked,,,," no leaks",,,, although at idle there did seam to be alot more oil in top valve area than normal,,,,Any more ideas ?

let-r-eat
07-08-2013, 11:19 PM
pull the head and tap head pressure port for a plug drilled and tapped for a gauge. spin it up and check pressure without the head installed.With the head installed you could insert a long 3/16 screw and put it in the pressure port in the back of the head. You will need to cut it the proper length. Install gauge and check. You can get an idea what this needs to look like by looking at the oil restrictor Essy sells that installs there.What filter are you running?

Big E tech
07-09-2013, 10:05 PM
Still have this same problem,,,,no oil pressure,,,, had the head sealed up and pressure checked,,,," no leaks",,,, although at idle there did seam to be alot more oil in top valve area than normal,,,,Any more ideas ?

Chances are that you have a crack or vacuum leak on the pick-up tube... Is your pan a Kevko or Canton pan?

7uptruckracer
07-10-2013, 07:03 AM
Do you run an oil restrictor in the head?

James Hall #1
07-10-2013, 07:24 PM
I've been running a K&N HP-2004 oil filter. Putting a gage on the block alone as let-r-eat said is a good idea, probably do that next. I've check the pickup tube, no leaks, gaskets on pump and pickup looks good with signs of leakage. Not for sure what brand the pan is but I have it for several year with no trouble before. Its does not have a oil restricter but I think it would be a good idea because there does seem to be a excessive amount of oil in the top of head. So much I suspect a crack in it, even though the machine shop can't find it. I do my own engines and have for years but this one has driven me nuts.

Big E tech
07-10-2013, 10:38 PM
I've been running a K&N HP-2004 oil filter. Putting a gage on the block alone as let-r-eat said is a good idea, probably do that next. I've check the pickup tube, no leaks, gaskets on pump and pickup looks good with signs of leakage. Not for sure what brand the pan is but I have it for several year with no trouble before. Its does not have a oil restricter but I think it would be a good idea because there does seem to be a excessive amount of oil in the top of head. So much I suspect a crack in it, even though the machine shop can't find it. I do my own engines and have for years but this one has driven me nuts.

Do yourself a favor and change the filter to a WIX 51515R.

We have found that the fibers used in the K&N oil filters begin to break down quickly. The cells expand when they absorb any moisture in the oil. Once these cells are expanded, they reduce the open area available for the oil to flow through, increasing pressure drop across the filter media. Once the pressure drop gets high enough, we've even seen the filter element begin to colapse upon itself...

Another good practice is to change the oil filter just before each race rather than letting it sit with oil in it before the event.

Have you checked your guage to make sure your low pressure readings are real?

Big E tech
07-10-2013, 10:41 PM
Is there any chance your cam bearings have a groove around the O.D.? If they do, you will have to plug the holes on top of each cam tower...

James Hall #1
07-11-2013, 05:39 AM
Will do on the filter, had 3 different gages on it,,, same reading on all 3, cam towers are plugged. Cars is pretty quick, just no oil pressure.

7uptruckracer
07-11-2013, 08:25 AM
Oil pump is good? sounds baffling

Big E tech
07-11-2013, 01:38 PM
Will do on the filter, had 3 different gages on it,,, same reading on all 3, cam towers are plugged. Cars is pretty quick, just no oil pressure.

When your engine machinist pressure tested the block and head, did they pressure test the water passages like normal, or did they actually plug all the oil holes and pressure up the oil galleys?

James Hall #1
07-11-2013, 07:52 PM
yes, new oil pump, even stretch the spring in one pump and it raised the pressure for just a few minutes and then dropped. The machinist plugged everything and pressured up the oil galleys in the head without the camshaft installed. I thought that they may have blocked the pressure off by doing that because the oil does travel throught the camshaft, right ? I'm off work tomorrow so I guess I'll check and recheck everything again, see if there something I've missed.