Gmc 7000 fixed

Posted a week or so ago about the troubles with our gmc 7000 truck not running well. Got it back on the road last week, haven't had time to post about it lately. I went to the junkyard, got a 366 tall deck intake with a quadrajet carb, installed a fuel pressure regulator, used distributor from junkyard, now it runs like a top. That tbi was the biggest waste of money, temperamental thing. Carb and vacuum advance distributor simplified things a lot and I couldn't be happier with the results. Now......time to sell some of these sensors and the tbi and tbi intake manifold... Anyone need parts? I'll make you a package deal :)
 
Good for you! I had a 1984 F250 that had a computer controlled carburetor! Had no way to adjust idle-and it needed adjusting! LOL It had the 300 straight six in it, so went to 'u pull it' and found a Ford Granada with everything I needed to eliminate the computer! Best day of that truck's life!
 
About computers on cars these days: The day-to-day reliability is better, but long term reliability still belongs to a plain carb and distributor. Once a gremlin gets into the computer stuff it can get very expensive to try to get it out. Frustrating for you after all the dough spent on the tbi.

About that manifold, I've never seen a tall deck manifold for a Q-jet. I'll have to keep my eye open as I could use one.
 
I followed your problems from the beginning.
What I never figured out for certain ,is you old system a true TBI or a electric/electronic, feedback carburetor?
 
(quoted from post at 09:28:37 01/26/15) I followed your problems from the beginning.
What I never figured out for certain ,is you old system a true TBI or a electric/electronic, feedback carburetor?

It was a TBI system.

I've worked on a lot of them but they all had the injectors removed as an IMPCO LP mixer installed on the throttle body. On that system the PCM controls the LP regulator instead of the injectors.
 
Yes I agree the problems with the primitive computer can be a real bear as we found out. It is a true tbi, not a computer controlled carb that was on the truck. Also, it's a former schwans refer bed, but not a schwans truck frame, it wasn't an lp. Lastly, it cost about a hundred bucks to get the intake manifold, distributor, and carb from the junkyard. Oh yeah and we used a carb conversion plate, it was intended for a holly carb but we put on a q jet. I want to thank for all the replies, learned a lot!
 
Glad you got it to work. What type of choke did the carb you got have? Electric? Maybe you got a manual swap over. Not sure what area your in but if it gets cold you'll want a functioning choke. Hope you can make some money with it now.
 
On the choke I'm not sure, I'm pretty sure you would say it is vacuum actuated? I know there's no electric to it and we didn't hook up a choke cable.
 
(quoted from post at 11:22:51 01/26/15) On the choke I'm not sure, I'm pretty sure you would say it is vacuum actuated? I know there's no electric to it and we didn't hook up a choke cable.

Most likely the choke is automatic. The vacuum part is a vacuum actuated pull-off, which will open the choke under acceleration, when the engine is not yet warm enough for the choke to already be open. If the choke is working like it should, leave it alone.
 
Temperamental? Wait till you try to live day to day with a carbed 366, especially running a Q-jet through an adapter. I also hope the truck does not need to pass inspection, since the governor is now inoperable. You also went from the possibility of getting 5-6 mpg to 2mpg if you are lucky. TBI was light years ahead of the carb it replaced in starting and fuel mileage, from S10's to medium duty. Good luck with your setup.
 
Sprint 6 appreciate your opinion, but truck didn't get good gas mileage to begin with, and also it didn't run. Now it runs. The question of mileage remains to be seen. The truck also doesn't require any inspections. It's farm plated and falls below the weight limit for any inspections
 


Glad to hear you got it running good. I did the same. Edelbrock Intake and carburetor. Runs good now, and am not looking back. TBI system, was a PITA when it got old.
 

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