Truck left me stranded today.

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,742
Reaction score
11,320
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
I have one that I can see, which I prefer, and the one in the carb. I would take the one out of the carb if there was any question. Why would having a second filter be an issue?
Even when new and clean it add resistance to the flow which in turn makes the pump work harder.

I would not remove the filter in the inlet of the carburetor, the reason being is if a tiny bit of rubber flakes off a hose or literally anything between the pump and the carb it'll get into the carb and possibly plug a circuit or cause the needle in the carb to stick open. If you remove any filter it should be the inline one. If you remove the carb filter then you should move the inline filter as close to the carb as possible, but keep in mind an external filter up on the manifold poses somewhat of an increase in fire risk.

In short the factory installed the filter in the inlet of the carburetor because that's what's best and that filter is enough filtration. With clean tanks there should be no reason that the filter in the inlet of the carb can't go 12 - 15K between changes, unless the truck sits a lot then just change it annually or every other year.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,228
Reaction score
6,209
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I have one that I can see, which I prefer, and the one in the carb. I would take the one out of the carb if there was any question. Why would having a second filter be an issue?
It could possibly be too much for your electric pump to overcome
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,228
Reaction score
6,209
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I have one that I can see, which I prefer, and the one in the carb. I would take the one out of the carb if there was any question. Why would having a second filter be an issue?
Does your carb have a long one in the inlet or is it short? If its a long one I would definitely stick with that as robyn said :)
 

sgrinavi

Supporting Member
Supporting Member
Joined
Feb 23, 2022
Posts
52
Reaction score
28
Location
Fort Myers, FL
First Name
Steve
Truck Year
1981
Truck Model
K20
Engine Size
350
It could possibly be too much for your electric pump to overcome

If I had the issue right after installing the filter I would agree, but it's been running fine for quite a while. I'm changing the coil, cap and IM this weekend, I also have a new mechanical pump coming along with the electric pump you suggested. I'll drive the hell out her and see if I can get it to repeat the problem afterwards.

It may end up being a carb issue, whenever I remove a fuel line, anywhere in the system, I have to manually prime it by taking the hose off the carb and running the pump until gas comes out.
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,742
Reaction score
11,320
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
If I had the issue right after installing the filter I would agree, but it's been running fine for quite a while. I'm changing the coil, cap and IM this weekend, I also have a new mechanical pump coming along with the electric pump you suggested. I'll drive the hell out her and see if I can get it to repeat the problem afterwards.

It may end up being a carb issue, whenever I remove a fuel line, anywhere in the system, I have to manually prime it by taking the hose off the carb and running the pump until gas comes out.
The priming thing that's a pump that has a hard time making enough flow / pressure not a carb issue.... Sounds like your pump is so weak it can't even purge air out with it attached to the carb...
 

sgrinavi

Supporting Member
Supporting Member
Joined
Feb 23, 2022
Posts
52
Reaction score
28
Location
Fort Myers, FL
First Name
Steve
Truck Year
1981
Truck Model
K20
Engine Size
350
The priming thing that's a pump that has a hard time making enough flow / pressure not a carb issue.... Sounds like your pump is so weak it can't even purge air out with it attached to the carb...
I'll slap the new one on there and see if that makes a difference. I'll probably put the mechanical on there too, I think I need bolts though
 

sgrinavi

Supporting Member
Supporting Member
Joined
Feb 23, 2022
Posts
52
Reaction score
28
Location
Fort Myers, FL
First Name
Steve
Truck Year
1981
Truck Model
K20
Engine Size
350
SO, after changing the fuel pump and most of the ignition components yesterday the same **** happened today. Fuel filter was empty, so I took the line off the carb and ran the pump until it gas came out. Put it together and it ran, took me another 7 miles and died again. I repeated and got within a couple blocks of home before it died again.

It's obvious that it's a fuel issue, thinking that that safety switch for the fuel pump had died I by passed it, she started and ran... for 100 feet. At this point I figured I could just get some gas in the line and get home. Remove the line from the carb, by pass the safety switch to run the pump and... nada, no fuel out of the line. Switch tanks, same thing.

Started bypassing the components, first thing to come off was the fuel pressure gauge. No help. Then I bypassed the fuel pressure regulator and boom! Fuel pouring out the line, connected the line to the carb and got home.

Could a pressure regulator fail intermittently? Seems odd to me.
 

Turbo4whl

Supporting Member
Supporting Member
Joined
Oct 30, 2019
Posts
2,896
Reaction score
6,512
Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
I'll slap the new one on there and see if that makes a difference. I'll probably put the mechanical on there too, I think I need bolts though
Save yourself headaches, put the mechanical pump back on. If it does not have a pump now, just a cover, make sure the push rod is there. There is also an inner cover that has two lower bols, then the pump bolts through it.

Put grease on the push rod to hold it up when you assemble the pump.

You must be registered for see images attach
You must be registered for see images attach


One of the less common mechanical pump failures is the cam lobe that pushes the pump push rod wipes.

That might be the only reason the previous owner went with an electric pump. This can be checked
 

Bextreme04

Full Access Member
Joined
May 13, 2019
Posts
4,192
Reaction score
5,096
Location
Oregon
First Name
Eric
Truck Year
1980
Truck Model
K25
Engine Size
350-4bbl
SO, after changing the fuel pump and most of the ignition components yesterday the same **** happened today. Fuel filter was empty, so I took the line off the carb and ran the pump until it gas came out. Put it together and it ran, took me another 7 miles and died again. I repeated and got within a couple blocks of home before it died again.

It's obvious that it's a fuel issue, thinking that that safety switch for the fuel pump had died I by passed it, she started and ran... for 100 feet. At this point I figured I could just get some gas in the line and get home. Remove the line from the carb, by pass the safety switch to run the pump and... nada, no fuel out of the line. Switch tanks, same thing.

Started bypassing the components, first thing to come off was the fuel pressure gauge. No help. Then I bypassed the fuel pressure regulator and boom! Fuel pouring out the line, connected the line to the carb and got home.

Could a pressure regulator fail intermittently? Seems odd to me.
Yes, they fail all the time. What electric pump are you running? What regulator? What carburetor? A stock mechanical pump and stock carburetor is all you need. The only legitimate reason I can think of for an electric pump to be installed is if an engine swap doesn't have a mechanical pump provision or the mechanical fuel pump lobe on the cam is worn off. You can check if that is the case on yours by putting your finger on the fuel pump pushrod and crank the engine. You should feel the pushrod moving in and out about 1/2" or so. If it doesn't move at all or very very little, you have a worn fuel pump lobe on the cam.

Edit: Fixed my mental lapse per turbo's post below
 
Last edited:

sgrinavi

Supporting Member
Supporting Member
Joined
Feb 23, 2022
Posts
52
Reaction score
28
Location
Fort Myers, FL
First Name
Steve
Truck Year
1981
Truck Model
K20
Engine Size
350
Save yourself headaches, put the mechanical pump back on. If it does not have a pump now, just a cover, make sure the push rod is there. There is also an inner cover that has two lower bols, then the pump bolts through it.

Put grease on the push rod to hold it up when you assemble the pump.

You must be registered for see images attach
You must be registered for see images attach


One of the less common mechanical pump failures is the cam lobe that pushes the pump push rod wipes.

That might be the only reason the previous owner went with an electric pump. This can be checked
I have a new mechanical pump and push rod, I need the inner cover, fittings for the fuel line to the carb and new bolts.
Yes, they fail all the time. What electric pump are you running? What regulator? What carburetor? A stock mechanical pump and stock carburetor is all you need. The only legitimate reason I can think of for an electric pump to be installed is if an engine swap doesn't have a mechanical pump provision or the mechanical fuel pump lobe on the cam is worn off. You can check if that is the case on yours by putting your finger on the fuel pump pushrod and crank the engine. You should feel the pushrod moving in and out about 1/2" or so. If it doesn't move at all or very very little, you have a worn fuel pump lobe on the cam.

Edit: Fixed my mental lapse per turbo's post below

This pump (Airtex E8016S Universal) and the, I assume, stock quadrajet. I have no issue with a mechanical pump, at this point I would certainly prefer it. I'll collect the parts and go from there. I'll probably swap the motor out at some point since I'm using 1 qt a month (400 miles) with no, apparent, leaks. My hang up right now is trying to figure out a good 5 speed for it without just throwing gobs of money at it.
 

Turbo4whl

Supporting Member
Supporting Member
Joined
Oct 30, 2019
Posts
2,896
Reaction score
6,512
Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
This pump (Airtex E8016S Universal) and the, I assume, stock quadrajet. I have no issue with a mechanical pump, at this point I would certainly prefer it.

Airtex are 1/3 the cost of another pump. And at work, only one in three Airtex pumps (intank) last more than a month.

Took awhile, but we (the mechanics) finally convinced the powers to be that it was cheaper to buy the factory pumps. Save two labor times and two tow jobs, on average, for every Airtex pump installed.
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
5,998
Reaction score
9,969
Location
Washington
First Name
Todd
Truck Year
1986
Truck Model
K20
Engine Size
454
Mechanical pumps are luck of the draw/junk sometimes from the box too, but I would still 100% have a mechanical pump if I had the option on my truck.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,228
Reaction score
6,209
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I have a new mechanical pump and push rod, I need the inner cover, fittings for the fuel line to the carb and new bolts.


This pump (Airtex E8016S Universal) and the, I assume, stock quadrajet. I have no issue with a mechanical pump, at this point I would certainly prefer it. I'll collect the parts and go from there. I'll probably swap the motor out at some point since I'm using 1 qt a month (400 miles) with no, apparent, leaks. My hang up right now is trying to figure out a good 5 speed for it without just throwing gobs of money at it.
did you just say 1 quart - 400 miles?????????????????????????????????????????????????????????????????????????????
Stall your truck again and then pull a spark plug or 3.
Thats a lot of oil. I would know my 2001 olds aurora did that. Blue smoke on every morning and you could get it to have slow-ness and dips while cranking if more than 1 day (valve seals, rings werent leaking that much)
How hot is the pump getting?
 

Latest posts

Forum statistics

Threads
42,156
Posts
910,226
Members
33,649
Latest member
MikeD
Top