The 1947 - Present Chevrolet & GMC Truck Message Board Network

Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board


Thread Tools Display Modes
Old 03-15-2019, 09:32 PM   #1
Senior Member
Join Date: Nov 2012
Posts: 740
Never assume anything...

Today I got my 67 GMC 3500 back from the muffler shop. It was dropped off there immediately after I got it back from a month-long stay at the brake shop. I was jones-ing to work on this truck after so long a separation, so I did work on it all day.
One of the first things that I did was replace the fuel sending unit with a brand new one that I bought several years ago, but never used.
When my son got home we got into the truck and drove towards the gas station, since I had noticed that the gas tank was a little low when replacing the sending unit.
We did not even make it five blocks and the truck just DIED. It would not start, so I popped the hood and checked the fuel filter. Half-empty. I figured that maybe the gas level was lower than I had initially thought, so I walked back home, got my 5-gallon jerry can, and drove in my car to the gas station that we were enroute to earlier.
After filling it up, then transferring most of the gas into the 67, I tried to start it again. Again, no gas was in the fuel filter. I tried priming the carb, thinking that maybe there was a big air bubble in the gas lines, but again, no gas. I then realized that there was a blockage in the gas line somewhere, so I drove my car back home and got my tool box. Upon returning, I unhooked the fuel line from the fuel pump and gas tank, then blew air into it. It went through with no issues, so I reattached it to the sending unit, then blew air into it from the disconnected fuel pump line. I could not get any air to go through it this time.
Even though that I knew that the sending unit was in new condition, I checked it anyway. With the fuel line detached from it I tried to blow air into the sending unit tube. It was totally BLOCKED, and I have no idea how this happened.
So I drove back home yet again, grabbed the old sending unit, and upon returning to the 67, installed it back into the gas tank. This time the truck started.
Today I learned never to assume that a new part is good, but I still have absolutely NO idea why it was clogged. I tried to unclog it with a piece of stiff wire, but only succeeded in getting a little air to hiss through it.
I was wondering if anyone else on here had even encountered a problem like this?
1981 Chevrolet C10 Deluxe Shortbed Stepside
1968 Chevrolet C10 Stepside Longbed
1967 GMC 3500 dually one-ton flatbed
HIGHWAY BY THE SEA is offline   Reply With Quote
Old 03-15-2019, 09:45 PM   #2
Senior Member
Join Date: Nov 2008
Location: Texarkana, TX
Posts: 444
Re: Never assume anything...

Any mud daubers in your area?
63 Biscayne
57 Chevy Truck (sold)
72 K20 Long bed stepside (wife's)
72 K20 Long bed 396 (flip or keep...?)
The latest build:
renegade6 is offline   Reply With Quote
Old 03-16-2019, 12:53 AM   #3
Senior Member
Join Date: Mar 2003
Location: Colfax-California
Posts: 5,666
Re: Never assume anything...

Length of pick-up tube connected to sender, leak in the tube?
kwmech is offline   Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -4. The time now is 10:31 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Copyright 1997-2013