1994.5 - 1997 7.3L Power Stroke Diesel  

lost oil pressure

Thread Tools
 
Search this Thread
 
  #1  
Old 10-07-2009, 07:16 PM
jleal_21's Avatar
jleal_21
jleal_21 is offline
Senior User
Thread Starter
Join Date: Jan 2008
Posts: 477
Likes: 0
Received 0 Likes on 0 Posts
Unhappy lost oil pressure

i had my oil cooler fixed by a friend of mine today but all didn't go as well as we wanted. after putting everything back together and starting the truck the oil pressure guage on the dash stays down to nothing but comes up if the engine is reved. this caught us by surprise and we are wondering what can cause this problem. please help..any pointers on what to look for will be greatly appreciated. thanks guys.
 
  #2  
Old 10-07-2009, 07:40 PM
BlueMule's Avatar
BlueMule
BlueMule is offline
Posting Guru
Join Date: Nov 2001
Location: Ft Scott
Posts: 1,743
Likes: 0
Received 1 Like on 1 Post
Remove the oil filter and check to see if the spring, disc and washer are in place in the relief valve.
 
  #3  
Old 10-08-2009, 11:37 AM
jleal_21's Avatar
jleal_21
jleal_21 is offline
Senior User
Thread Starter
Join Date: Jan 2008
Posts: 477
Likes: 0
Received 0 Likes on 0 Posts
is the relief valve on the filter mounting base? what else can cause this? where is the oil pressure sensor located?
 
  #4  
Old 10-08-2009, 12:36 PM
Hussler's Avatar
Hussler
Hussler is offline
Postmaster

Join Date: Sep 2007
Location: Medford Oregon
Posts: 4,195
Likes: 0
Received 4 Likes on 3 Posts
Oil pressure switch is on the HPOP reservoir.
 
  #5  
Old 10-08-2009, 01:01 PM
Brown Falcon's Avatar
Brown Falcon
Brown Falcon is offline
Hotshot
Join Date: Jul 2008
Location: Thomasville, GA
Posts: 11,231
Received 123 Likes on 83 Posts
If the engine is running your oil pressure is fine...
 
  #6  
Old 10-08-2009, 06:34 PM
kellens's Avatar
kellens
kellens is offline
Mountain Pass
Join Date: Dec 2005
Posts: 136
Received 0 Likes on 0 Posts
I had this happen to me on a school bus i was working on once. we had like 10 psi at low idle and could only get 20 psi at high idle on a cold engine. Check the pressure relief/regulator valve. its in the oil filter header. Newer engines have a snap ring holding in the disc and spring, on older engines it was just "pinned" in place (basically center punch marks to deform the aluminum an hold the disc in). Check on this. I'm almost certain this is your problem. Also it wouldn't hurt to hook up a real oil pressure gauge to see that your working with.
 
  #7  
Old 10-08-2009, 08:33 PM
BlueMule's Avatar
BlueMule
BlueMule is offline
Posting Guru
Join Date: Nov 2001
Location: Ft Scott
Posts: 1,743
Likes: 0
Received 1 Like on 1 Post
Originally Posted by jleal_21
is the relief valve on the filter mounting base? what else can cause this? where is the oil pressure sensor located?
Yes, the relief valve is in the oil filter header. Once you remove the filter you'll either see the valve or the whole where it's supposed to be.



That pic is from Brians 97 so you will see that it has the snap ring holding everything in place, on earlier models the washer was just staked in place with a few dimples in the housing

There need to be 3 pieces in the hole, the spring goes 1st, then the disc and finallly the washer.

Without that valve all of you oil will just bypass the filter and you'll hardly make and oil pressure.

Neither Ford or IH sell those pieces separate, the only way to get them is with a new header assembly or from a parts truck.

 
  #8  
Old 10-08-2009, 09:28 PM
jleal_21's Avatar
jleal_21
jleal_21 is offline
Senior User
Thread Starter
Join Date: Jan 2008
Posts: 477
Likes: 0
Received 0 Likes on 0 Posts
hey thanks alot guys, i'll check this first thing in the morning. so i just remove clean and put back together then? thanks for the pics rodney they were really helpfull.
 
  #9  
Old 10-08-2009, 09:34 PM
FARM69's Avatar
FARM69
FARM69 is offline
Postmaster
Join Date: Jan 2004
Location: Kearney, Nebr
Posts: 3,207
Likes: 0
Received 0 Likes on 0 Posts
Awsome information guys. Tried to rep ya Blue but you know the story...
 
  #10  
Old 10-12-2009, 11:28 PM
jleal_21's Avatar
jleal_21
jleal_21 is offline
Senior User
Thread Starter
Join Date: Jan 2008
Posts: 477
Likes: 0
Received 0 Likes on 0 Posts
well i checked it and everything seems to be inplace. i didn't remove anything but the filter and i think the valve should be good cause i mess with it pushing on it and it seemed like the spring and everything were good. what else should i check for? i have to make a 600 mile trip on wednesday and would like to have it working poperly. thanks for the help so far.
 
  #11  
Old 10-13-2009, 12:40 PM
johnstoys2's Avatar
johnstoys2
johnstoys2 is offline
Senior User
Join Date: Jan 2006
Location: Woodleaf NC
Posts: 240
Likes: 0
Received 0 Likes on 0 Posts
I would verify the oil pressure with a guage at the engine & go from there. the sensor could of be bad or the guage in the dash itself.
 
  #12  
Old 10-13-2009, 02:22 PM
DZL JIM's Avatar
DZL JIM
DZL JIM is offline
PREMIUM SPONSOR
Join Date: Sep 2003
Location: North East Ohio
Posts: 2,611
Received 183 Likes on 83 Posts
The dash oil psi gauge is run off the sender on the HPOP reservoir. Run a mech gauge off that port and confirm what's going on.
 
__________________
'96 7.3 F-350 Reg Cab 4x4 - bought new.
'04 6.0 E-350 custom 4x4
'08 6.4 F-550 Reg Cab 6 spd 4x4
'17 6.7 F-250 KR ccsb 4x4
  #13  
Old 10-15-2009, 06:21 PM
jleal_21's Avatar
jleal_21
jleal_21 is offline
Senior User
Thread Starter
Join Date: Jan 2008
Posts: 477
Likes: 0
Received 0 Likes on 0 Posts
well i havent been able to get a mech gauge on it to see what its doing but i did buy a new sending switch at the stealership and that didn't fix nothing. i'm stating to worry a little. what do yall think? is my worry not neccecary.
 
  #14  
Old 11-11-2009, 10:19 PM
edgef250stroker's Avatar
edgef250stroker
edgef250stroker is offline
New User
Join Date: Nov 2009
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
someone please help me with this oil pressure question???

i was woundering if anyone can help me out. my strokers oil pressure seems kinda low. it sits on the "N" on normal and thats it. doesnt go higher or lower...is that bad? if so what can i do to fix that??
 
  #15  
Old 11-12-2009, 10:48 PM
oldbird1965's Avatar
oldbird1965
oldbird1965 is offline
Fleet Owner

Join Date: Aug 2004
Location: AZ
Posts: 20,282
Received 125 Likes on 103 Posts
Originally Posted by edgef250stroker
i was woundering if anyone can help me out. my strokers oil pressure seems kinda low. it sits on the "N" on normal and thats it. doesnt go higher or lower...is that bad? if so what can i do to fix that??
Its a dummy gauge, activited by 6psi of oil pressure, thats it.
 


Quick Reply: lost oil pressure



All times are GMT -5. The time now is 02:32 AM.