fuel delivery issues ain't getting none

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.

DanMcG

Full Access Member
Joined
Jun 28, 2014
Posts
1,076
Reaction score
1,891
Location
Central NY
First Name
Dan
Truck Year
1978 1985
Truck Model
k10 k10
Engine Size
400 350
Well that worked, blew some some air in the tank, blew gas a few feet. I tried cranking it over after that figuring it was primed and nothing, not a drop pumped by the pump.

Thanks everyone, especially Snooks for the suggestions. I got a couple days before the new pump gets here from Rock auto so I should have plenty of time to get the old one off.
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,451
Reaction score
8,695
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
Sorry it was an e8090 airtex
 

DanMcG

Full Access Member
Joined
Jun 28, 2014
Posts
1,076
Reaction score
1,891
Location
Central NY
First Name
Dan
Truck Year
1978 1985
Truck Model
k10 k10
Engine Size
400 350
Well I'm sitting here waiting for the rain to stop before I get the new pump on, and was thinking.....If the old pump was weak, would that explain why the carb bowl is empty? Is it possible that it was only pumping enough to get it to run, then when it sits for any period of time what little is in the bowl evaporates. Hasn't been on the road in a while so it only idles in the yard and any attempt to give it gas it stumbles.
 

Snoots

Full Access Member
Joined
Jan 23, 2013
Posts
8,752
Reaction score
18,200
Location
Georgia
First Name
Roger
Truck Year
1973
Truck Model
Jimmy Sierra
Engine Size
350 w/203
I had a similar problem many years ago.

Fuel pump died.
Replaced fuel pump.
Didn't help.
Come to find the new fuel pump was for a 2-bbl carb.
Got one for a 4-bbl carb.
Problem solved.

Don't forget this:

You must be registered for see images attach


You'll need a longer bolt to hold the push rod up while installing the new pump.
 

DanMcG

Full Access Member
Joined
Jun 28, 2014
Posts
1,076
Reaction score
1,891
Location
Central NY
First Name
Dan
Truck Year
1978 1985
Truck Model
k10 k10
Engine Size
400 350
It funny but that boss for the bolt must not be drilled thru to the rod as there is no bolt in it and no oil seepage. Maybe because it's a 86 warranty block?


Well it's in and working great, but now the 5/16 return line is spraying gas out of cracks in the line. never saw them till now, so thats next on the list.
Thanks everyone who helped, I appreciate all the advice.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I had a similar problem many years ago.

Fuel pump died.
Replaced fuel pump.
Didn't help.
Come to find the new fuel pump was for a 2-bbl carb.
Got one for a 4-bbl carb.
Problem solved.

Don't forget this:

You must be registered for see images attach


You'll need a longer bolt to hold the push rod up while installing the new pump.
Say what now. There are different pumps for 2 barrels? Mine had a two barrel. It does keep up while running but still. Interesting
 

Snoots

Full Access Member
Joined
Jan 23, 2013
Posts
8,752
Reaction score
18,200
Location
Georgia
First Name
Roger
Truck Year
1973
Truck Model
Jimmy Sierra
Engine Size
350 w/203
Say what now. There are different pumps for 2 barrels? Mine had a two barrel. It does keep up while running but still. Interesting

I thought it was odd too but, the 4bbl pump was taller through the chamber than the 2bbl model.
I don't know :confused: but it works.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I thought it was odd too but, the 4bbl pump was taller through the chamber than the 2bbl model.
I don't know :confused: but it works.
What issues did it cause in yours? Was it a new 2 barrel pump that didnt seem to work right out the box and a new 4 barrel pump that did?
 

Snoots

Full Access Member
Joined
Jan 23, 2013
Posts
8,752
Reaction score
18,200
Location
Georgia
First Name
Roger
Truck Year
1973
Truck Model
Jimmy Sierra
Engine Size
350 w/203
It would start ok
It would idle ok
It would take off slowly
Then just acted like it ran (or was running) out of gas at about 20MPH.

The 4bbl pump I got just had a larger diaphram area.

Oddly, the new pump I recently installed (about 3 months ago) has a smaller diaphram area and so far, has posed no problems.

I've even punched it from 75MPH and it scoots. I'm running the same Q-Jet.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
It would start ok
It would idle ok
It would take off slowly
Then just acted like it ran (or was running) out of gas at about 20MPH.

The 4bbl pump I got just had a larger diaphram area.

Oddly, the new pump I recently installed (about 3 months ago) has a smaller diaphram area and so far, has posed no problems.

I've even punched it from 75MPH and it scoots. I'm running the same Q-Jet.
Curious. Thanks for the input and response to old thread
 

Snoots

Full Access Member
Joined
Jan 23, 2013
Posts
8,752
Reaction score
18,200
Location
Georgia
First Name
Roger
Truck Year
1973
Truck Model
Jimmy Sierra
Engine Size
350 w/203
Curious. Thanks for the input and response to old thread

I wish I had a more definitive answer for you but it baffled me. Even the original pump had a large diaphram but it sprang a leak in the casing so initially, I thought the small diaphram was better technology.

If it works, I ain't fixin' it.
 

DanMcG

Full Access Member
Joined
Jun 28, 2014
Posts
1,076
Reaction score
1,891
Location
Central NY
First Name
Dan
Truck Year
1978 1985
Truck Model
k10 k10
Engine Size
400 350
It would start ok
It would idle ok
It would take off slowly
Then just acted like it ran (or was running) out of gas at about 20MPH.

The 4bbl pump I got just had a larger diaphram area.

Oddly, the new pump I recently installed (about 3 months ago) has a smaller diaphram area and so far, has posed no problems.

I've even punched it from 75MPH and it scoots. I'm running the same Q-Jet.


You got me wondering about this 2bbl-4bbl thing so I looked around a little. the pump for a six cylinder looks the same but with less pressure and gpm. :shrug:
 

Forum statistics

Threads
44,167
Posts
950,749
Members
36,283
Latest member
Cantrell299
Top