Results 1 to 10 of 10

Thread: OPS/fuel pump FUSE keeps popping

  1. #1
    Join Date
    Apr 2014
    Location
    USA, FL. Eustis
    Posts
    19

    Default OPS/fuel pump FUSE keeps popping

    I just replaced my OPS, fuel pump, relay and added a Leroy Diesel Fuel pump relay To my 96 Suburban and my 20A fuse keeps blowing any low speeds under load 90% of the time. I went 3miles up a winding mountain at a speed of 25 to 35 mph and blew that fuse 23 times! Good thing I had a bunch of fuses going up to 30A!!! Also this morning I blew the fuse putting it in reverse and idling backwards, wen I replaced it I used the peddle a bit AKA 1500-2000 RPM and she went fine. Think there is another issue...... thinking it could be Transmition or what ever that fuse goes to..... just a SWAG...... this is driving me nuts!!!!!!! Anyone have any help that could be thrown my way along with some luck

    Oh when the fuse pops oil pressure is in the 30 to 50 PSI range and i was driving from FL to WV and the only time they popped is when I was pulling of the highway to get fuel and when I was going up the mountain going around curves at around 15-35 MPH
    1986 K5 Blazer (Restoration in progress): stage II racing "K" transmission with +4 quart pan, Banks turbo, new GP’s, 3rd rebuilt IP, Rebuilt injectors, Stud Grille, Aluminum Radiator, Halogen light upgrade, fog lights, and added factory Cruise and rear power window

    1996 GMC Suburban K2500 6.5l diesel (Restoration in progress). Running on a DB2 IP, new GP’s, rebuilt injectors, rebuilt transmission with +4 quart pan, dibble din GPS radio, USB and 12v charging in the door pullers, Chasing down the wire gremlins at the moment.......

    I think I’m a glutton for punishment

  2. #2
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,573

    Arrow

    Load-related electrical issues are most commonly caused, at least in part, by failed/failing engine and/or tranny mounts. Look for a damaged or strained harness between the powertrain and frame/chassis, any location that's moving (more than it should) when it shouldn't, and/or loose or poor connections.

    Increasing the fuse capacity will only relocate the point of failure. Fuses are cheap and easy to remedy. Components and harnesses, not so much. It's often helpful to downsize the fuse, making it easier to duplicate the problem under specific conditions. Have lots of fuses of the correct capacity handy.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  3. #3
    Join Date
    Apr 2014
    Location
    USA, FL. Eustis
    Posts
    19

    Default

    Can anyone tell me where that fuse goes to and comes from in the vehicle
    1986 K5 Blazer (Restoration in progress): stage II racing "K" transmission with +4 quart pan, Banks turbo, new GP’s, 3rd rebuilt IP, Rebuilt injectors, Stud Grille, Aluminum Radiator, Halogen light upgrade, fog lights, and added factory Cruise and rear power window

    1996 GMC Suburban K2500 6.5l diesel (Restoration in progress). Running on a DB2 IP, new GP’s, rebuilt injectors, rebuilt transmission with +4 quart pan, dibble din GPS radio, USB and 12v charging in the door pullers, Chasing down the wire gremlins at the moment.......

    I think I’m a glutton for punishment

  4. #4
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    6,057

    Default

    Quote Originally Posted by leo5150 View Post
    I just replaced my OPS, fuel pump, relay and added a Leroy Diesel Fuel pump relay...
    Was the fuse blowing before you did all this? If not, you know where to look...
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC, John Deere X758
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  5. #5
    Join Date
    Apr 2014
    Location
    USA, FL. Eustis
    Posts
    19

    Default

    The fuse was blown and I did not realize it when I sent it to the shop as explained in my earlier post. The mechanic changed the OPS (for a pretty penny to) that is located under the intake behind the fuel filter housing unlike my 86 K5 6.2l. He had told me about the fuse and that it was blown, then he said that if it keeps blowing I should get the Leroy Diesel relay and that should fix it. So I did..... along with the fuel pump (ACDelco) because I could. Well the damm fuse still pops....... I also just changed the fuel filter because the old one looked brown..... so you are saying that the fuse loops back to the OPS and fuel pump??? I checked the fuel pump by unplugging the relay while running and the engine kept working so the fuel pump is good....... what other tests can you suggest
    1986 K5 Blazer (Restoration in progress): stage II racing "K" transmission with +4 quart pan, Banks turbo, new GP’s, 3rd rebuilt IP, Rebuilt injectors, Stud Grille, Aluminum Radiator, Halogen light upgrade, fog lights, and added factory Cruise and rear power window

    1996 GMC Suburban K2500 6.5l diesel (Restoration in progress). Running on a DB2 IP, new GP’s, rebuilt injectors, rebuilt transmission with +4 quart pan, dibble din GPS radio, USB and 12v charging in the door pullers, Chasing down the wire gremlins at the moment.......

    I think I’m a glutton for punishment

  6. #6
    Join Date
    Apr 2014
    Location
    USA, FL. Eustis
    Posts
    19

    Default

    Well the fuse just popped again and every fuse I put in is popping it’s the keys out. Now I need to figure out where to check to see where the problem is.
    1986 K5 Blazer (Restoration in progress): stage II racing "K" transmission with +4 quart pan, Banks turbo, new GP’s, 3rd rebuilt IP, Rebuilt injectors, Stud Grille, Aluminum Radiator, Halogen light upgrade, fog lights, and added factory Cruise and rear power window

    1996 GMC Suburban K2500 6.5l diesel (Restoration in progress). Running on a DB2 IP, new GP’s, rebuilt injectors, rebuilt transmission with +4 quart pan, dibble din GPS radio, USB and 12v charging in the door pullers, Chasing down the wire gremlins at the moment.......

    I think I’m a glutton for punishment

  7. #7
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    6,057

    Default

    Fuses blow because the circuits they protect are drawing too much current. So, either that fuse is feeding a faulty component or you have a wire that intermittently shorts to ground.

    Installing a larger fuse only makes it more likely you'll have an electrical fire.

    First place I'd look is the wiring running back to the fuel pump. Second, any wiring associated with that circuit that jumps from the engine to the body or frame.
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC, John Deere X758
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  8. #8
    Join Date
    Oct 2003
    Location
    West Chicago, Illinois
    Posts
    209

    Default

    1995 Chev 4X4 1500 Suburban 6.5 TD,Phazer Gear Kit from JK, High Capacity Water Pump Kit from JK. Special Calibration fan clutch W/8 blade fan from JK
    1995 Chev 4X4 2500 Suburban 6.5 TD>>SOL-D (parts car)
    1999 Chev 4X4 2500 Suburban 454 "Gas Hog" with Hiniker C-Plow

  9. #9
    Join Date
    Apr 2014
    Location
    USA, FL. Eustis
    Posts
    19

    Unhappy

    Sorry it is taken me so long to post the reply to this, but it turns out the wiring harness was rubbing against the steering wheel shaft…… I really needed my glasses for this and sometimes it’s best to look for the easiest fix possible……
    1986 K5 Blazer (Restoration in progress): stage II racing "K" transmission with +4 quart pan, Banks turbo, new GP’s, 3rd rebuilt IP, Rebuilt injectors, Stud Grille, Aluminum Radiator, Halogen light upgrade, fog lights, and added factory Cruise and rear power window

    1996 GMC Suburban K2500 6.5l diesel (Restoration in progress). Running on a DB2 IP, new GP’s, rebuilt injectors, rebuilt transmission with +4 quart pan, dibble din GPS radio, USB and 12v charging in the door pullers, Chasing down the wire gremlins at the moment.......

    I think I’m a glutton for punishment

  10. #10
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,573

    Arrow

    Thanks for the update.

    Easy is good. We like easy.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •