Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

'87 sub - 20 AMP fuel pump fuse location?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by shane74, Mar 21, 2005.

  1. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    Anybody know where this is? I think I blew mine. I can't find it under the hood. Is it back by the fuel pump? It's not in the fuse block itself is it? Any help appreciated. Thx.
     
  2. k20

    k20 3/4 ton status

    Joined:
    Sep 9, 2001
    Posts:
    5,068
    Likes Received:
    0
    Location:
    Mineral Springs, NC
    if your lookin on the wiring diagrams and see that....i think that is for later trucks. The fuel pump fuse on my 87 is ECMB on the fuse box.
     
  3. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    I just talked to my brother-in-law (the guy I bought it from) and he told me where to look on the firewall. He had it happen to him once. If it's not the fuse and/or relay, then the new (less than a year old) fuel pump is bad. I really don't want to be working on that. They are a major PITA.
     
  4. k20

    k20 3/4 ton status

    Joined:
    Sep 9, 2001
    Posts:
    5,068
    Likes Received:
    0
    Location:
    Mineral Springs, NC
    yeh the relay is on the firewall, but when I swapped my FI, the instructions said to change the fuse to a larger one, and I thought that thing was on the firewall, all my wiring diagrams show it there.....dang thing was ecmb on the fuse box.
     
  5. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    Yeah, after you posted, a light bulb went off. I saw that in the fuse panel. I pulled it and it wasn't blown. I am going to trace the power back to the pump. If I have power but no action...well, looks like I'll be spending some quality time w/ my half full 41 gal. tank :( At least the pump itself isn't too expensive. Replacing them is about as much fun as getting your wisdom teeth pulled out through your @ss w/ a pick axe.
     
  6. Hossbaby50

    Hossbaby50 3/4 ton status

    Joined:
    Sep 1, 2001
    Posts:
    8,972
    Likes Received:
    0
    Location:
    Peoria, AZ
    Cut a hole in the floorpan to access the sending unit instead of dropping the tank out. Then just put the piece of floor back in when you are done with some little tabs or something.

    Harley
     
  7. k20

    k20 3/4 ton status

    Joined:
    Sep 9, 2001
    Posts:
    5,068
    Likes Received:
    0
    Location:
    Mineral Springs, NC
    before you do that, there is a way you can test the pump. On the relay on the firewall, there should be a red wire with a little connector on it. Push a wire into that, and then put the other end of the wire on the positive battery terminal. That is providing power directly to the pump.
     
  8. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    I sorta did that. I heard the pump kick on for about 1 second. I also checked the voltage at the wiring harness to the pump. I am getting only 8 volts to the pump. I don't know how much is supposed to be getting to it. I thought it was supposed to be a full 12 volts. Anyway. I jumpered the wire from the battery to the pump, but I didn't use the red wire. I think I jumpered the orange & tan/white wire. According to the wiring diagram, the orange and tan/white wire are supposed to connect w/ the ign. on and fire up the pump. I unplugged the harness to jumper it. It didn't fire. I'll retry using the red wire w/ the harness plugged in and see what happens. At least if it fires that way, I'll know it's the relay and not the pump. That'd be a welcome relief.

    The other odd thing before all of this started, my wife plugged in her cell phone charger to the lighter and it blew the fuse that controls it and the radio. Conicidence maybe?
     

Share This Page