eratic oil pressure

[BobJohnson]

I have a 93 D350 with about 165,000 miles. when I got it had abuot 60,000miles on it. the oil and all filters have been changed every 3-4,000 miles since i have had it. this last week the oil guage has been showing normal pressure untill it warms up then it drops to the bottom of the guage at different times. when you accelerate it drops then usually comes back up when you let off. any prognosis or suggestions will be appreciated. also can someone recomend a person in the Yucaipa California area that works on our vehicles? Yucaipa is aproximately 10 miles east of San Bernardino or 90 east of L. A.



thanks for the help.



Bob Johnson

 

[southpaw]

oil presure

Bob, the first thing I would check is the sending unit and wire that attaches to same. heat and oil takes its toll on it and its easy to check. It,s on the left side lower mid of block aft of the steering pump. If that is the problem it takes a special socket to remove a deep thin-wall of 1 1/8 inch but check to make sure of size , i,m going on 3 year memory here. If it is the sending unit it is standard from almost any auto supply and the socket is 4x more than the sender. Hope this helps its an easy fix.

 

[southpaw]

to answer your other question someone in your area oh yeh you are in an area where several members are located and can give you good info. also you are in the center of the so. cal . dodge-cummins club that have bombing meets they will flex your expense account . and will know how to fix anything.

 

[BobJohnson]

Thanks Southpaw,

I installed a mechanical guage off of the oil filter and it says the oil pressure is runnig between 35 and 55lbs depending on hot,cold, at idle or on the freeway. i will change out the sending unit as soon as i get one.

thanks for the help.

 

[mysteryman]

oil pressure relief valve

From your description I would be concerned with the oil pressure relief valve sticking . Dirt or fine metal chips occasionally will get past the oil filter. They can score the bore that the relief valve/piston rides in. If it sticks open or partially open.

Oil pressure will drop as the engine temperature goes up and or the engine rpm goes up... This problem is however rather easy to fix. .

The oil pressure relief valve is located in the oil filter adapter plate just above the oil filter . Remove the piston valve and spring from the bore. Polish out any scores on the piston and bore with crocus cloth... Clean bore and piston then reassemble. Refer to your FACTORY Dodge or Cummins service manual

for detailed pictures and or description of the system

Thanks Southpaw,

I installed a mechanical guage off of the oil filter and it says the oil pressure is runnig between 35 and 55lbs depending on hot,cold, at idle or on the freeway. i will change out the sending unit as soon as i get one.

thanks for the help.