carb problems - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**Stephen717** · 09-08-2019, 07:24 PM

Hello everyone. since my last posting I've done quite a bit more work to the frame to the point that I am nearly ready to swap the motor over and prepare to swap the body over. My current problem is that I went to start her the other day and noticed that the Monojet was leaking fuel. Not a big deal as I have 4 2 jets lying around. 2 of them are in pieces and need rebuilt. The other 2 came off a car with a running tri power setup (the guy was going a different direction and and someone snagged the middle carb before I could get to it so I bought the intake and 2 outer carbs). I have tried both and found that neither of them leak but when I try to start the truck (with either 2 jet on the 250) it sounds like it doesn't want to pick up fuel to stay running. I am a novice on carbs and have only ever rebuilt 1 with a friend (and he did most of the work) so I'm not sure exactly what's going on. Can anyone help with this?

**HO455** · 09-08-2019, 07:59 PM

If they are true tripower carbs they won't have a choke blade nor will they have idle circuits in them. Making them unusable for a single carburetor engine.
Tripower set ups used only the center carburetor for the idle circuit and the outboard carburetors were used like the secondarys on a 4 barrel carburetor. Post some pictures of them. And we will be able to ID them for you.

geezer#99 · 09-08-2019, 08:34 PM

And we’d like to see what you used for an adaptor to mount that carb.
Well, at least I would!

**Stephen717** · 09-08-2019, 11:19 PM

Thanks. I will get pics when I get to work in the morning. I used an adapter from summit. Part # SUM-200010. Thanks for the quick replies

**special-K** · 09-09-2019, 08:42 AM

If you end up needing a carb rebuild and don't feel confident about taking that on, K&K Automotive on 355 in Frederick is a great bench work shop for rebuilding components. And they are reasonable on price.

**Stephen717** · 09-10-2019, 08:45 AM

That's good to know. Here is the adapter I'm using and the pics of one of the 2 carburetors. I looked underneath them and sure enough there's nowhere for air to come through for proper idle. I had a 2 jet that had this provision and rebuilt it with all the best parts from 2 of the carbs (as I plan on rebuilding them all before I put them on the tri power setup) but now I don't have the right fuel fitting (that big but looking thing) for the 2 jet I have. The only one that fits it is for a 3/8 fitting instead of the smaller fuel line. Does anyone know where I can get this?

geezer#99 · 09-10-2019, 09:17 AM

That carb has mix screws and a choke so should work.
The inlet fitting was available at quadrajet parts.com but I see their web isn’t working.

But I see mikes might have them.

https://www.carburetor-parts.com/Car...rts_c_977.html

09-08-2019, 07:24 PM	#1
Stephen717 Senior Member Join Date: Aug 2016 Location: Loris South Carolina Posts: 429	carb problems Hello everyone. since my last posting I've done quite a bit more work to the frame to the point that I am nearly ready to swap the motor over and prepare to swap the body over. My current problem is that I went to start her the other day and noticed that the Monojet was leaking fuel. Not a big deal as I have 4 2 jets lying around. 2 of them are in pieces and need rebuilt. The other 2 came off a car with a running tri power setup (the guy was going a different direction and and someone snagged the middle carb before I could get to it so I bought the intake and 2 outer carbs). I have tried both and found that neither of them leak but when I try to start the truck (with either 2 jet on the 250) it sounds like it doesn't want to pick up fuel to stay running. I am a novice on carbs and have only ever rebuilt 1 with a friend (and he did most of the work) so I'm not sure exactly what's going on. Can anyone help with this?

09-08-2019, 07:59 PM	#2
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 11,393	Re: carb problems If they are true tripower carbs they won't have a choke blade nor will they have idle circuits in them. Making them unusable for a single carburetor engine. Tripower set ups used only the center carburetor for the idle circuit and the outboard carburetors were used like the secondarys on a 4 barrel carburetor. Post some pictures of them. And we will be able to ID them for you. __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban (the WMB),1988 S10 Blazer (the Stink10 II),1969 GTO (the Goat), 1970 Javelin, 1952 F2 Ford OHC six 4X4, 29 Model A, 72 Firebird (the DBP Bird). 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377

09-08-2019, 08:34 PM	#3
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,736	Re: carb problems And we’d like to see what you used for an adaptor to mount that carb. Well, at least I would!

09-08-2019, 11:19 PM	#4
Stephen717 Senior Member Join Date: Aug 2016 Location: Loris South Carolina Posts: 429	Re: carb problems Thanks. I will get pics when I get to work in the morning. I used an adapter from summit. Part # SUM-200010. Thanks for the quick replies

09-09-2019, 08:42 AM	#5
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,851	Re: carb problems If you end up needing a carb rebuild and don't feel confident about taking that on, K&K Automotive on 355 in Frederick is a great bench work shop for rebuilding components. And they are reasonable on price. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

09-10-2019, 08:45 AM	#6
Stephen717 Senior Member Join Date: Aug 2016 Location: Loris South Carolina Posts: 429	Re: carb problems That's good to know. Here is the adapter I'm using and the pics of one of the 2 carburetors. I looked underneath them and sure enough there's nowhere for air to come through for proper idle. I had a 2 jet that had this provision and rebuilt it with all the best parts from 2 of the carbs (as I plan on rebuilding them all before I put them on the tri power setup) but now I don't have the right fuel fitting (that big but looking thing) for the 2 jet I have. The only one that fits it is for a 3/8 fitting instead of the smaller fuel line. Does anyone know where I can get this? Attached Images

09-10-2019, 09:17 AM	#7
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,736	Re: carb problems That carb has mix screws and a choke so should work. The inlet fitting was available at quadrajet parts.com but I see their web isn’t working. But I see mikes might have them. https://www.carburetor-parts.com/Car...rts_c_977.html



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