i am wondering on my 93 f150 4.9l if the oil pump is going bad. it ticks when at high rpm and you can barely hear it when idling. i have tried thicker oil and stuff but doesnt seem to work. and when i have truck off after running and the hood open i hear the oil draining back into the pan. i have a motocraft filter and am running 20w-40 oil right now.

what i am thinking is the pump is not pumping enough at higher rpms.

 

i had replaced the lifters with comp cam ones in april i had also used break in oil and did the 2000rpm thing for 20min

 

I would start by installing a mechanical oil gage and see what you really have and go from there.
If you do replace the oil pump I woud go with a High volume pump not a high pressure. also check the end play on your crank shaft as the In lines are known for wearing thrust bearings this usually show its self as a leaking rear main seal

 

There the same pump. Higher Vol will make more pressure. Your trying to push more oil through the same system...... more back pressure. Some companies call um high pressure and some call um high volume. there the same thing. Just one is trying to market it to people with lower oil pressure.

Bottom line is if your pressure is low then your pump is bad or you might have a bearing problem. the High volume pumps are to be used with lose bearing causing low oil pressure. a high volume pump in a good motor will make too much pressure. .... Been there done that. When you have a 100 psi gauge and you bury the needle when the motor is cold.... that's a problem The oil pressure in my 390 would just push seals out of the motor. about once a month I had to replace valley gaskets as they would just get pushed out. Never blew a oil filter tho! Good motor craft filters! LOL

If you have low oil pressure you need to find out why. If a high mileage motor your bearing could be getting bad. Only real way is to pop the pan and use a plastic gauge on a rod and main bearing and see what your clearances are. Could be a hand full of other things.

If you changed lifters a while back I would pop the valve covers off and see if you had a rocker come lose. I bought a used motor with a lifter tick, got it home to find someone installed the wrong push rod. new lifter, rod, and rocker ... good as new. I always like to check the last thing that was done for a mistake ... happens to all of us!

 

ur choices are standard volume standard pressure

high pressure standard volume

or high pressure high volume


melling std pressure.... M-68

melling high volume....M-68HV

melling high pressure....M-68A

 

I'v never pushed seals out, Igess any thing is posable maybe I'v just been lucky

 

well that cleared that up thanks I gess it wasent luck at all

 

i will have to buy a manual guage to see when i have time. i might take a look at the rockers cause they may need to be re tightened after running it for a while. i dont seem to loose oil. the guage on the dash is at about O and just today i took a left hand turn and the guage dropped all of the way to LOW then went back to the O. i never had this problem befor.


am i able to just change the spring for a little more pressure?

and where do i hook a guage up to test the pressure?

 

well i know the pump might be worn and the lifters might be bad. i decided to check the oil finally after the needle moved that much and no reading on dip stick so i go to store with it quick get a qt of lucas stabilizer and 2 qts of cheap 20w-50. well it took the lucus, and 2qts of the oil so i go back in and get 3 more qts for just in case after it is full. so 3.5 qts later it is good. its actually been sine july 4th since i did an oil change and checked it. i went mudding that weekend and didnt notice any oil leaking. then 2wks ago i went mudding again which im thinking i was 3qts low that time.

well these engines r good runers for running low on oil, let me say that.

cant notice any place where it is leaking.

 

the 300/6 4.9l is a great motor Iv had 2 in the past in fact the 1 i pulled out of my 85 F150 is still going in my buddys truck it had 250,000 on it whin I parted it out in 2004 and I still see my old 93 running around town
To Bad they quit building them

 

Glad you decided to check the oil , number 1 reason for no oil pressure....Lew

 

i just didnt think at first at checking that cause i havent had any problems in the past with loosing oil. since i owned it in may of 2008 no leaks. well it runs better now. im going to look at hooking up a guage in the cab for sure now. how do those hook up on the engine? i will probably mount it on the pillar of the door.

 

just find oil sending unit on the side of the block and put a T in between it & the mortor
I want to say it on the drivers side
also put some teflon tape on all the threds when you put it toughter

 

uhm no do not use teflon tape... it will prevent the factory gauge/warning light from making ground and it will not read

but yes it is on the drivers side

 

Can anybody that has put the T in the oil pressure sending units place post a pic and materials used. I want to install a electric sending unit for a accurate oil pressure gauge and also still have the factory oil pressure gauge show correctly. I was going to put a mechanical unit with line ran into cab but don't want to take chance for leak so... Also the electric sending unit for the gauge is too big to fit where the sending unit is now. Thanks.