Mechanical fuel pump

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highdesertrange

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efing Midas. they also left a bolt off the rod access plate. now I am confused an 86 should have a return line. are you saying it didn't have one before all this? and yes a return line helps keep it from vapor locking. don't listen to those idiots at Midas. also was it an ACDelco fuel pump? it also could be a split in the rubber line between the pump and the tank. it also appears they did not replace the 3/8's rubber line at the pump. highdesertranger
 

75gmck25

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There are only two bolts on the pump, and they left one off? And they may have left a cracked rubber line?

The lever on the pump has a relatively strong spring and the rod on the block pushes against the lever to make the pump work. The two cover bolts must hold the pump and lever in place so that the rod moves the pump lever full travel. Those bolts being tight is very important.

Bruce
 

Ricko1966

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1986 should definitely have a return line find it and hook it up.Try to get a bolt in the access plate if you have problems with that let us know. My take on this and my first course of action, before doing anything is disconnect line at the carb and route it to a catch can, got fuel it's carb or fuel filter problem.No fuel disconnect the supply line at the pump and temporarily provide a different fuel source.A motorcycle tank. Lawn mower can with a piece of brake line through the cap etc. Now start it and see if the carb fills and the truck runs, Now see if it drives. This eliminates everything prepump. Still have a problem rig a return line to your temp can. Still have a problem now it's between the pump and the carb.Doing it this way eliminates the I hooked up the return line we'll wait and see if that fixed it. I found a split line on top of the tank maybe that was it, I changed the fuel cap I think that was the problem.I hate guessing,I like knowing.Customers are pissed if they have to return 3 times to get it fixed, and it makes the tech look like he really. doesn't know what the problem is.

As for effing Midas I'm not defending them, but we don't know the whole situation.Maybe it went in with a bolt broke off in the block and the return line plugged, maybe the tech even said something about this and was told to send it out the way it came in.That covers their ass in the world we live in.
 
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highdesertrange

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if it was there or not is really not the issue. they should have fixed it while they were in there. or at least pointed it out and given him some options. their attitude on the return line speaks volumes. highdesertranger
 

AuroraGirl

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Mine doesn't have but a dribble in it when I change the filter and it runs just fine. I have had to drop both my tanks and rinse them out. The little filter in the carb will stop up real quick if you don't have clean fuel. I had to cut the filters I have changed open to see what was stopping them up. It would go from running just fine to coasting dead in no time. All is well after dropping the tanks. There was a powdery substance in the driver side tank that would drop out of suspension if left to sit, but would mix first time you moved the truck and go right to the filter and stop it up.
i had that before i changed my tank, sender, and carb. it would only idle on full throttle LOL. But if i let it sit for a weeek it would work again. Since replacing tank, and seeing all the crap inside, i have not had that issue again
 

Ricko1966

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if it was there or not is really not the issue. they should have fixed it while they were in there. or at least pointed it out and given him some options. their attitude on the return line speaks volumes. highdesertranger

This is just 1 example but when I was working at the shop where we had a full machine shop we were supposed to do whatever, I don't remember anymore,but a piece of the block that opened into an oil galley fell off in the steamer.We called the customer and he was mad at us that someone previously had epoxied this back together before he bought it. It was fine until we steamed it. It would have lasted for ever if we had just done the machine work without cleaning it I'm not defending Midas and agree if the return line was bypassed before and a bolt was broke off before they should have called him. But if they had there would be people on here right now going they probably broke it and are just trying to get more money,or the fuel line couldn't have been that way before or it wouldn't have run they are trying to rip him off.Ive kind of adopted a damned if you do damned if you don't attitude from too many years of doing this for a living.I would have called and have been the guy waiting all day for the call back at 15 minutes till close when the customer calls and says, just put it back like it was I'm on my way to pick it up.
 

Ricko1966

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Another good one I had nothing to do with just ended up buying the car, hearing the story and fixing the mistakes made. I bought a car knowing it had stripped threads in a front wheel hub.Previous owners version was yea I took it to tires plus and those idiots overtightened the lugs and stripped 2. I got the car home, investigated, and someone had replaced the integral front rotors with larger hub and hat style rotors, someone also had put alloy wheels on it. The car had lug bolts for stock integral brg rotors and steel wheels the stock lug bolts were way too short and barely catching any threads.I was able to chase the treads in the hub and use correct length bolts, problem solved.How many or people do you think he told, tires plus screwed up my car, and how many people do you think they told. I'm sorry I started writing this now, I'm just tired of the tech always being the bad guy in every situation.There are, and I am one tons of honest techs.
 
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Rusty Nail

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The return line lets fuel return to the tank when the float closes and the carburetor dead-heads the fuel flow , and it helps keep the fuel cooler. Without a return you get hot fuel trapped in the line and it increases the chance of vapor lock.

If your truck has a 3 port sender, then you should use all 3 ports connections at the fuel pump. The metal return line connection should be strapped to the frame very close to the 3/8" fuel line input to the pump.

Bruce
That's what I was thinking about.

Ive read page one and im hung up HARD on Midas installing the wrong pump or modifying your truck anywhere beyond stock.
I bet AIRTEX brand is okay for that truck for a year at least.

You CANNOT miss the GM 5/16 return line running down the inside of the frame because it's. right.there.
But I cant see it in the pix.
Great pix btw. You even have warshers under the carb mounting bolts - good job!
But IF the truck is without factory liquid return line - which moron at Midas approved installing the wrong pump?
I dont really care what page 2 says because I think it has the wrong fuel pump on it. Im gonna look anyway but


Oh. You took it off.
Ran fine before right?
Full stop.

Midas had to butch because you did but neither of you should have. Undo the butch and put it back like it was. Buy the right fuel pump and stay away from Midas - everything should be fine.
 
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Bextreme04

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That's what I was thinking about.

Ive read page one and im hung up HARD on Midas installing the wrong pump or modifying your truck anywhere beyond stock.
I bet AIRTEX brand is okay for that truck for a year at least.

You CANNOT miss the GM 5/16 return line running down the inside of the frame because it's. right.there.
But I cant see it in the pix.
Great pix btw. You even have warshers under the carb mounting bolts - good job!
But IF the truck is without factory liquid return line - which moron at Midas approved installing the wrong pump?
I dont really care what page 2 says because I think it has the wrong fuel pump on it. Im gonna look anyway but


Oh. You took it off.
Ran fine before right?
Full stop.

Midas had to butch because you did but neither of you should have. Undo the butch and put it back like it was. Buy the right fuel pump and stay away from Midas - everything should be fine.
lol, this thread is from last year.... how did it even get brought back up?
 

Grit dog

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Well, there's alot of creative diagnoses and implication of intent, lol. Some folks should be actors, if they're not already!

But forget all the weird comments and focus on the one thing that is most likely the issue.
"I removed the steel fuel line from the carburetor and crank the truck over. No fuel..."
Old pump and line, worked fine, but leaked.
New pump, no fuel when cranking with fuel line disconnected. Either new fuel pump is bad, or something preventing fuel from getting to it.
Barring a coincidence that something upstream of the pump went wrong literally 15 miles after a new fuel pump, it's entirely possible on a rusty 35 year old truck of unknown/poor condition, it's most likely the fuel pump, IMO.
But check filter too.
And then I remembered, you had a fuel pump problem recently as well.
And towards the end of that thread, after 3 fuel pumps and 9 pages of back n forth, you never even said if you got it fixed. So, at this point, if you're now on your 4th new pump, I'm going to say it's not the pump? PS, does Midas charge you for every pump replacement? I can't even imagine having a truck towed in for something that takes like 15minutes, $23, and a 9/16 wrench to replace....

Not knowing what you've done in the meantime (has it run good for 10 tanks of gas since August, or been parked and you're now again trying to get it running?) of if you've even verified that it runs great off of a gas can and not the tank, not alot more suggestions to give. Good luck figuring it out.
 
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Bextreme04

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Well, there's alot of creative diagnoses and implication of intent, lol. Some folks should be actors, if they're not already!

But forget all the weird comments and focus on the one thing that is most likely the issue.
"I removed the steel fuel line from the carburetor and crank the truck over. No fuel..."
Old pump and line, worked fine, but leaked.
New pump, no fuel when cranking with fuel line disconnected. Either new fuel pump is bad, or something preventing fuel from getting to it.
Barring a coincidence that something upstream of the pump went wrong literally 15 miles after a new fuel pump, it's entirely possible on a rusty 35 year old truck of unknown/poor condition, it's most likely the fuel pump, IMO.
But check filter too.
And then I remembered, you had a fuel pump problem recently as well.
And towards the end of that thread, after 3 fuel pumps and 9 pages of back n forth, you never even said if you got it fixed. So, at this point, if you're now on your 4th new pump, I'm going to say it's not the pump? PS, does Midas charge you for every pump replacement? I can't even imagine having a truck towed in for something that takes like 15minutes, $23, and a 9/16 wrench to replace....

Not knowing what you've done in the meantime (has it run good for 10 tanks of gas since August, or been parked and you're now again trying to get it running?) of if you've even verified that it runs great off of a gas can and not the tank, not alot more suggestions to give. Good luck figuring it out.

The OP last posted on this thread Nov 13, 2020...... why are people all of a sudden giving him advice on his fuel pump problem?!?!?! He either figured it out himself, or his truck has been sitting for the last year
 

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