4.0 oil pump question

[handyman1355]

when my truck is cool the oil pump does not seem to get the oil pressure up as quick as it should. some rattle for just a split second until the pressure gets up. Do yall think that a new oil pump would help with the cool starting rattle?

 

[Ronv]

I think there is supposed to be a check valve to keep the oil in the passageway, possible a bit of dirt got in the way of the check-ball. I had the same problem but stepped up my oil changes for a couple of months and it finally went away.

Ron V

 

[AllanD]

More often than not a 4.0 with an oil pressure issue has a gummed up pickup.

AD

 

[kimcrwbr1]

Run 1/2 quart of ATF in it for about 100 miles then change the oil and use a motorcraft filter. See if that helps what kind of filter do you have in it.

 

[ragajungle]

I have the same God Awful lower end bearing clatter when I start up after she sits for more than 10 hours...I tried almost 3 different oil filters to no avail. Would Seafoam in the crank case work?

(sorry to jack this thread) but I have been fighting this issue too!

 

[handyman1355]

thread jacker

I have the same God Awful lower end bearing clatter when I start up after she sits for more than 10 hours...I tried almost 3 different oil filters to no avail. Would Seafoam in the crank case work?

(sorry to jack this thread) but I have been fighting this issue too!

thats quiet alright as long as we get an answer. by the way I put a mechanical gauge on mine and the oil pressure is about 50 psi at a cold start up but seems slow to get there should the needle jump right away to that pressure? if so maybe the pickup is clogged somewhat.

 

[ragajungle]

handy,
I replaced the oil sender in my B2 and before that the gauge barely touched (L) for Low. After it was okay and jumped straight to the middle range. I understand that this sender is a on/off switch and doesn't have the capacity to give actual range.



That Aside other people here and on other forums with the 4.0L have the same sporadic gauge issue and replacing the sender has almost always fixed it. I also noted that others with this motor Also have the clatter/knocking on cold start up with "good" pressure indicated on the gauge so maybe it incidental to a stopped up pick-up tube?

 

[handyman1355]

pick up tube

handy,
I replaced the oil sender in my B2 and before that the gauge barely touched (L) for Low. After it was okay and jumped straight to the middle range. I understand that this sender is a on/off switch and doesn't have the capacity to give actual range.



That Aside other people here and on other forums with the 4.0L have the same sporadic gauge issue and replacing the sender has almost always fixed it. I also noted that others with this motor Also have the clatter/knocking on cold start up with "good" pressure indicated on the gauge so maybe it incidental to a stopped up pick-up tube?

I think i will pull the lower pan and try to get the pickup tube off for cleaning.

 

[sholzy]

I think i will pull the lower pan and try to get the pickup tube off for cleaning.

Do you plan on pulling the motor? That's the only way to get the pan off.

 

[handyman1355]

wrong

Do you plan on pulling the motor? That's the only way to get the pan off.

I said lower pan. and i have already pulled the pickup tube but it was clean. put it back together and just hope it holds together.

 

[sholzy]

On a 2001 4.0 you can remove the pan without pulling the motor? Everything I've read and heard you have to pull the motor to do that.

 

[handyman1355]

pan

On a 2001 4.0 you can remove the pan without pulling the motor? Everything I've read and heard you have to pull the motor to do that.

mine has an 2 peice pan upper and lower i know the lower pan can be removed in the truck.

 

[sholzy]

mine has an 2 peice pan upper and lower i know the lower pan can be removed in the truck.

The lower pan is the "bowl" part of the pan?