1987 Silverado fuel issue

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bucket

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@bucket I was adding to while you were liking,so hope it's still good.

Yeah, I "liked" it before the edit, but I still like it now too. The things you mentioned there brought back a lot of memories about customers that really didn't know their cars. And a funny fuel pump story too.
 

hamm

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I won't be able to try any new suggestions right away. Am in the middle of replacing the last bit of older foundation on my house. Still working on breaking out the old concrete. Lots of fun.
 

Ricko1966

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Yeah, I "liked" it before the edit, but I still like it now too. The things you mentioned there brought back a lot of memories about customers that really didn't know their cars. And a funny fuel pump story too.
Yep I've been sitting here reflecting about all the stupid sh!t I've been through with this profession and at the time maybe was maddening but now I just laugh at all the absurdities.
 

hamm

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The connector for the tank unit. It should be accessible through the LR wheel well.

I usually jump at the relay. Just disconnect it, make sure the B+ is hot,
I believe you are envisioning a vehicle with a tank in the rear. Mine has dual side tanks. Only the right tank is in use because the left one has a leak. [As an aside, my fuel gauge stopped properly registering when this fuel system problem arose. I get no change when changing to the left tank, which is empty]

If I recall, just the "A" lead is hot at the connector. I'll look again when I have time.
 

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I believe you are envisioning a vehicle with a tank in the rear. Mine has dual side tanks. Only the right tank is in use because the left one has a leak. [As an aside, my fuel gauge stopped properly registering when this fuel system problem arose. I get no change when changing to the left tank, which is empty]

If I recall, just the "A" lead is hot at the connector. I'll look again when I have time.
Nope, I was referring to a side tank, specifically the left side. I don't recall where the connector(s) was on a dual tank setup. When I referred to 'B+' I meant the power supply circuit, not the terminal position. Now that I think about it, seems like the connector is near the switching valve. Just can't picture it.
 
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KnuckleBuster

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@KnuckleBuster I don't have a problem whacking a gas tank with a rubber mallet. And I certainly don't care if you do it...
Just to be clear, I NEVER said to whack the tank with a rubber mallet. Hand slap only. It doesn't take much.
 

Ricko1966

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Lots and lots and lots of people smack em with a board a mallet, a hammer. And I don't care! I merely said I was told to quit doing it and why. And from now on if you'll just drop it I'll tell everyone the first thing to do if there car won't start is slap the gas tank with their hand.
 

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KnuckleBuster

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Lots and lots and lots of people smack em with a board a mallet, a hammer. And I don't care! I merely said I was told to quit doing it and why. And from now on if you'll just drop it I'll tell everyone the first thing to do if there car won't start is slap the gas tank with their hand.
I can't believe we're still on this. I only meant to clarify what I said. Didn't need research with photos and more 'expert' comments from other forums. We differ on opinion, which was stated several posts ago. I'm getting the impression that you are a last-word-kinda guy. You can have it...I'll respond no more.
 

Ricko1966

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I can't believe we are still on it either! Why are we?I haven't said a word about it in a week,but somebody thought they needed to bring it back up,I didn't. I don't care,if when or how you gently slap gas tanks. There I had the last word have a nice day.
 

hamm

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Update: Finally got back to this project.

I found that the fuse I believe is marked "crank 3A"(hard to read) was blown. After replacing that fuse, I now hear the fuel pump relay activating about one second after turning on the ign key. I still have crank but no run condition. It will run on a prime. Any idea what might have caused that fuse to blow?
 

hamm

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Update: I found the connector near the fuel tank and disconnected that to run a test on the fuel pump. Was feeling around the wires on top of the tank and felt one which seemed to run to an odd location on top of the tank. I pulled on it, lightly, and it popped loose. Dropping the tank to investigate.
 

hamm

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Anybody? I have tried looking up what a "crank fuse" does, but most references say that the engine won't crank without it. But mine DID crank without it - just no fuel coming to the TBI. Can't figure how that fuse relates to my fuel supply issue.
 

hamm

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The wire I broke off at the tank is a ground to the frame, so I'll still have to go ahead drop the tank to fix that. It's almost out anyway now.

I put 12v to the red pigtail out of the fuel pump relay connector. It appears that it should be a direct test for the fuel pump, but I don't get 12v at the connector by the tank. I'll try to trace that line backward. It must be broken or shorted.
 

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