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

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-21-2015, 02:58 PM   #1
jammer3096
Registered User
 
Join Date: Apr 2014
Location: republic, mo
Posts: 57
New fuel pump but gas

Hey guys I'm about done with a motor swap out and I've replaced all new parts including a fuel pump. I haven't turned over the motor yet but is it possible to get gas to the carburetor by pumping just the carb before turning over motor or does the motor have to be turning over to get the pressure. I'm just checking to see if everything's working before we turn it over and I'm not getting any fuel to the carburetor.Thanks.
jammer3096 is offline   Reply With Quote
Old 02-21-2015, 03:05 PM   #2
enaberif
Registered User
 
Join Date: Jan 2009
Location: Calgary, AB
Posts: 1,181
Re: New fuel pump but gas

When installing a mechanical fuel pump you need to make sure the rod sits against the fuel pump. I fought with this recently and it drove me NUTS.

The easiest thing I found was put a small amount of red grease on the end of the push rod and it would hold it up.

For the carb you can fill up the float bowl to help it kick over.
enaberif is offline   Reply With Quote
Old 02-21-2015, 03:10 PM   #3
jammer3096
Registered User
 
Join Date: Apr 2014
Location: republic, mo
Posts: 57
Re: New fuel pump but gas

Thanks but the question I have is can you manually pull the gas by pushing the accelerator on the carburetor or do you need to turn the motor over with the key.
jammer3096 is offline   Reply With Quote
Old 02-21-2015, 03:30 PM   #4
YourBuddy'sTruck
Registered User
 
YourBuddy'sTruck's Avatar
 
Join Date: May 2013
Location: Catawba Island, OH
Posts: 203
Re: New fuel pump but gas

I'm no expert, but your accelerator piston only pumps gas in little spurts and it gets its supply from the float bowl area.
So, no, you will not get fuel up there without cranking it over and thereby running the fuel pump.
As enaberif suggested, fill the bowl and then you can see the piston pump work with your accelerator arm.

I'd just crank it over if everything was hooked up and ready.
You Float Bowl will be full by the time half your pistons mad a revolution.

Last edited by YourBuddy'sTruck; 02-21-2015 at 03:31 PM. Reason: typos...grrr.
YourBuddy'sTruck is offline   Reply With Quote
Old 02-21-2015, 04:00 PM   #5
hamjet
Registered User
 
hamjet's Avatar
 
Join Date: Apr 2013
Location: South Westerlo, New York
Posts: 1,325
Re: New fuel pump but gas

If you're talking cam breakin, you could always unbolt the pump and pump it by hand to fill the carb, unless you get an electric pump theres not much you can do. loosen the line where it comes in the pump to get the gas that far first.
__________________
Thanks, Joe..
1969 C/10, 348 C.I., 3X2 bbl. V8, 2004r , LWB.
hamjet is offline   Reply With Quote
Old 02-21-2015, 09:43 PM   #6
70C10Toejam
Hellasick
 
70C10Toejam's Avatar
 
Join Date: Jul 2006
Location: Death Moans, IA
Posts: 876
Re: New fuel pump but gas

I'm guessing you want to prime the carb with fuel. You can fill it with gas through the breather tube. See arrow in pic for a qjet. Others have one too. If you have a qjet I would put in 1/4-1/2 cup. If yours has a sight glass , put in enough to see it. All you need is enough to last until the pump takes over.

Just use a squeeze bulb, old baster, bulb for sucking snot from kids nose, eye dropper whatever.
Attached Images
 
__________________
I keep two MAGNUMS in my desk. One's a gun, and I keep it loaded. The other's a bottle and it keeps ME loaded. I'm Tracer Bullet. (Calvin and Hobbes)

This life was a test. It was only a test. If this had been an actual life, you would have received instructions on where to go and what to do.

RED meat is not bad for you...FUZZY BLUE/GREEN MEAT is bad for you!!!!!!!!!!!!!

BUILT FORD TOUGH WITH CHEVY STUFF--sticker at Goodguys
70C10Toejam is offline   Reply With Quote
Old 02-21-2015, 10:18 PM   #7
haysonj
Registered User
 
haysonj's Avatar
 
Join Date: Dec 2007
Location: Santa Maria, Ca.
Posts: 1,423
Re: New fuel pump but gas

To answer your question the fuel pump only works when the engine is turning over.
__________________
69 Chevy 4x4 383 Power
haysonj is offline   Reply With Quote
Old 02-22-2015, 02:40 PM   #8
kxmotox247
Senior Member
 
kxmotox247's Avatar
 
Join Date: Jul 2002
Location: Champaign, IL
Posts: 1,396
Re: New fuel pump but gas

I've seen people take a blow gun and shoot a short blast of air in thru the gas filler neck (using their hand to seal it off around the blow gun). Almost instantly it pushes fuel all the way to the pump and maybe even the carb.
I would suggest turning down the air on the regulator to do this. Seems like it would be possible to do damage to the carb if you did it with too much pressure and for too long.
kxmotox247 is offline   Reply With Quote
Old 02-22-2015, 03:44 PM   #9
haysonj
Registered User
 
haysonj's Avatar
 
Join Date: Dec 2007
Location: Santa Maria, Ca.
Posts: 1,423
Re: New fuel pump but gas

Quote:
Originally Posted by kxmotox247 View Post
I've seen people take a blow gun and shoot a short blast of air in thru the gas filler neck (using their hand to seal it off around the blow gun). Almost instantly it pushes fuel all the way to the pump and maybe even the carb.
I would suggest turning down the air on the regulator to do this. Seems like it would be possible to do damage to the carb if you did it with too much pressure and for too long.
I once split a 55 gal drum with only 5 psi from a air compressor so I would be very careful doing that
__________________
69 Chevy 4x4 383 Power
haysonj is offline   Reply With Quote
Old 02-22-2015, 04:24 PM   #10
frankslagoon
Registered User
 
Join Date: Jan 2014
Location: Wasilla Alaska
Posts: 537
Re: New fuel pump but gas

Quote:
Originally Posted by haysonj View Post
I once split a 55 gal drum with only 5 psi from a air compressor so I would be very careful doing that
So true. nothen makes me happier than blowen a bunch of gas in my new cab job. I think I'd rather dump a little gas in the carb throat. put the air cleaner back on. I made that mistake before and the timing was off and back fired thru the carb. of course I got gas outside the carb while dumpen it in and fire in the hole. now I always take time to put the air cleaner back on. usually the trk will run for 5 or 10 seconds which should get fuel flowen from the tank. might have to do it twice?
frankslagoon is offline   Reply With Quote
Old 02-22-2015, 04:33 PM   #11
ssxty8
Registered User
 
Join Date: Apr 2014
Location: PR
Posts: 85
Re: New fuel pump but gas

I've used starting fluid with good results.
ssxty8 is offline   Reply With Quote
Old 02-22-2015, 11:31 PM   #12
mechanicalman
Registered User
 
Join Date: Jun 2014
Location: Glendale, Arizna
Posts: 1,642
Re: New fuel pump but gas

Quote:
Originally Posted by 70C10Toejam View Post
I'm guessing you want to prime the carb with fuel. You can fill it with gas through the breather tube. See arrow in pic for a qjet. Others have one too. If you have a qjet I would put in 1/4-1/2 cup. If yours has a sight glass , put in enough to see it. All you need is enough to last until the pump takes over.

Just use a squeeze bulb, old baster, bulb for sucking snot from kids nose, eye dropper whatever.
Good idea...I like your style!
mechanicalman is offline   Reply With Quote
Old 02-22-2015, 11:53 PM   #13
enaberif
Registered User
 
Join Date: Jan 2009
Location: Calgary, AB
Posts: 1,181
Re: New fuel pump but gas

You don't need to use a baster I just used the end of a pop can and made a spout.
enaberif is offline   Reply With Quote
Reply

Bookmarks


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 10:03 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com