Tri power idle
Thread Starter
Racer
Joined: Sep 2012
Posts: 459
Likes: 6
From: Fort Worth Texas
Tri power idle
My tripower starts up and idles at ~600 when cold. When fully warm (at about 210) it idles up at 850-900. Not sure if this is normal, thought maybe the secondary's weren't fully closing when it gets warm, or maybe something else?
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
Mine did until getting the fast idle cam working correctly. Which tri-power engine do you have the 400 or the 435? The 435's will have a higher hot idle due to the cam, lifter and compression differences between the 2 engines.
Mines a 435 and hot idles at 950. Cold idle is now 1000, before the cold idle speed was 650.
Mines a 435 and hot idles at 950. Cold idle is now 1000, before the cold idle speed was 650.
Thread Starter
Racer
Joined: Sep 2012
Posts: 459
Likes: 6
From: Fort Worth Texas
Mine did until getting the fast idle cam working correctly. Which tri-power engine do you have the 400 or the 435? The 435's will have a higher hot idle due to the cam, lifter and compression differences between the 2 engines.
Mines a 435 and hot idles at 950. Cold idle is now 1000, before the cold idle speed was 650.
Mines a 435 and hot idles at 950. Cold idle is now 1000, before the cold idle speed was 650.
Last edited by bellaireroad; Apr 10, 2014 at 03:39 PM.
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
Does your choke work properly and is the choke stove (heat coil) in the manifold working properly? They work with each other to get the correct cold idle speed.
The factory shop manual has the procedure for the correct adjustments and somewhere in my dealer days service bulletins is a great 4 page one for the tri-powers. If you need any of them, send me a PM with your snail mail address and they'll be in the mail to you.
Your hot idle speed is on the high side but that is set on the linkage side of the center carb with the choke fully open. Make sure the end carbs throttle blades are completely closed. Will require adjusting the links at each carb if not closing completely.
Last edited by 1Fordman; Apr 11, 2014 at 10:22 AM.
Thread Starter
Racer
Joined: Sep 2012
Posts: 459
Likes: 6
From: Fort Worth Texas
Yes, check the operation of your fast idle cam. Before you cold start note the position of the fast idle cam, then step on the accelerator to set the fast idle cam and choke. Both should change position ( cam should drop down to a different position and choke to a more closed position) which cracks the throttle blade open and sets up the cold idle speed. The fast idle cam has steps on it and an adjustable screw contacts the steps which adjusts the cold idle speed.
Does your choke work properly and is the choke stove (heat coil) in the manifold working properly? They work with each other to get the correct cold idle speed.
The factory shop manual has the procedure for the correct adjustments and somewhere in my dealer days service bulletins is a great 4 page one for the tri-powers. If you need any of them, send me a PM with your snail mail address and they'll be in the mail to you.
Your hot idle speed is on the high side but that is set on the linkage side of the center carb with the choke fully open. Make sure the end carbs throttle blades are completely closed. Will require adjusting the links at each carb if not closing completely.
Does your choke work properly and is the choke stove (heat coil) in the manifold working properly? They work with each other to get the correct cold idle speed.
The factory shop manual has the procedure for the correct adjustments and somewhere in my dealer days service bulletins is a great 4 page one for the tri-powers. If you need any of them, send me a PM with your snail mail address and they'll be in the mail to you.
Your hot idle speed is on the high side but that is set on the linkage side of the center carb with the choke fully open. Make sure the end carbs throttle blades are completely closed. Will require adjusting the links at each carb if not closing completely.
I sent you a PM with my address, would like to have those articles! Thanks!
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
I'll get them copied and in the mail, got your address in the PM.
Sounds like your choke and fast idle are fine, "drops RPM when accelerator tapped". I'm thinking curb idle speed adjustment needed for hot idle speed, that's done on the linkage side. Also while on that side, set the mixture screws as they also have an effect on idle speed.
I use a vacuum gauge to set the mixture screws. For me it works better than the RPM drop method. You can watch the gauge and easily hit the sweet spot!
Sounds like your choke and fast idle are fine, "drops RPM when accelerator tapped". I'm thinking curb idle speed adjustment needed for hot idle speed, that's done on the linkage side. Also while on that side, set the mixture screws as they also have an effect on idle speed.
I use a vacuum gauge to set the mixture screws. For me it works better than the RPM drop method. You can watch the gauge and easily hit the sweet spot!
