Any tri-power guys ?
Thread Starter
Burning Brakes
Joined: Jul 2004
Posts: 783
Likes: 38
From: Mankato Mn
Any tri-power guys ?
This Vette isn't mine but a friend of mine. It's a 69 427 tri-power with factory side exhaust, #s matching etc. He has had the carbs rebuilt twice. The problem is, it starts & runs fine when cold. Runs great on the road, but when he gets in town after driving, it kills at every light. It will not idle & its very hard to start after that. Has anyone got any ideas where to start looking for the problem ?
Racer
Joined: Nov 2001
Posts: 499
Likes: 4
From: Loxahatchee FL
Follow the link and go through the adjustments section. Just because the carbs have been rebuilt doen't mean they are adjusted correctly.
http://www.corvettefaq.com/c3/tripower/
Rick L.
http://www.corvettefaq.com/c3/tripower/
Rick L.
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
He will never get this running right.
Tell him that I will take the Vette of him for a lousy price of course so he is hassle free.
Seriously, the tripower is the best running carb system I had installed and I tried several carbs. The basic adjustment is what counts.
That it starts so hard, could this be a ignitioon issue, menaing, does the starter have problems to turn the hot engine over ?
Rgds. Günther
He will never get this running right.
Tell him that I will take the Vette of him for a lousy price of course so he is hassle free.
Seriously, the tripower is the best running carb system I had installed and I tried several carbs. The basic adjustment is what counts.
That it starts so hard, could this be a ignitioon issue, menaing, does the starter have problems to turn the hot engine over ?
Rgds. Günther
Burning Brakes
Joined: Mar 2006
Posts: 915
Likes: 2
From: Lima, OH -- 69 L71 427/435hp
I've had similar problems before after the restoration and rebuild.
I had a stripped carb stud on the center carb and didn't know it and it did the same thing, so double check all carb stud nuts are tight and the studs don't turn. The reason is as it heats up the metal expands and raises just enough to start sucking air. I used a heli-coil, tightened it back up and it ran fine. You can also spray some WD40 around the base of the center carb when it's warmed up and see if the RPM's go up and that will tell you if your sucking air also.
Recently it started doing it again, but not as dramatic. I hadn't tuned the carb since the above problem, but the motor has been more broken in since then. So I backed out the air/fuel screw and fed it a bit more air and now it will idle w/o wanting to die off and at stop lights I don't need to feather the gas to keep it from dying off.
Edit: Also you can try putting a wooden clothespin(s) on the fuel line in front of the block to help dissipate some of the heat to help prevent vapor locking.
I'll assume you have it hooked up correctly, here's pic of mine.
Hope this helps
I had a stripped carb stud on the center carb and didn't know it and it did the same thing, so double check all carb stud nuts are tight and the studs don't turn. The reason is as it heats up the metal expands and raises just enough to start sucking air. I used a heli-coil, tightened it back up and it ran fine. You can also spray some WD40 around the base of the center carb when it's warmed up and see if the RPM's go up and that will tell you if your sucking air also.
Recently it started doing it again, but not as dramatic. I hadn't tuned the carb since the above problem, but the motor has been more broken in since then. So I backed out the air/fuel screw and fed it a bit more air and now it will idle w/o wanting to die off and at stop lights I don't need to feather the gas to keep it from dying off.
Edit: Also you can try putting a wooden clothespin(s) on the fuel line in front of the block to help dissipate some of the heat to help prevent vapor locking.
I'll assume you have it hooked up correctly, here's pic of mine.
Hope this helps
Last edited by 1ARACE; Apr 30, 2010 at 10:04 AM.
Le Mans Master
Joined: Mar 1999
Posts: 5,399
Likes: 985
From: Itasca IL
First and foremost, check the adjustment of the secondary linkage to ensure the secondary carbs are fully closed at idle. Second, I would verify the float levels.
Contact Eric Jackson at www.vintagemusclecarparts.com. He restored my tripower and other Holleys for me with superb results. There is a tutorial for Holley set-up and adjustment on his website as well.
Contact Eric Jackson at www.vintagemusclecarparts.com. He restored my tripower and other Holleys for me with superb results. There is a tutorial for Holley set-up and adjustment on his website as well.
