Fuel System: Why does heat do this???

[Hawklover]

For quite some time I find that after a run on the highway when the engine is hot (duh) and I come to a light or stop for slow moving local traffic the curb idle drops very low to the point of stalling many times. When cold the curb idle is spot on and will stay that way.....until the car is driven and the engine gets to operating temps.....and the car has to stop.

I can get a perfect 650 idle, but just do not want to adjust the curb idle up to an artificial point to over compensate for when the engine reaches operating temps.

Any ideas???

[TWChamp]

What year, model, and engine, and what gas are you using?
Ethanol gives me plenty of problems, which the better gas without corn usually doesn't. All gas boils much easier than the good gas of the 60's and 70's, so try to keep the fuel lines and carb as cool as possible. I made a heat shield for my 50 Champion, which helped a lot. I also added white plastic wire wrap over the fuel line from the pump to the carb. So far my 50 Land Cruiser is doing fine with no added shields.

[Hawklover]

Champ, R-1 engine, I use 93 Sunoco, to which I add TEL in qt containers (till the stocks are depleted) Candidly the car runs better in the cold winter than in the heat of the summer. I have several heat gaskets under my AFB carb, and removed the heat rise from the top of the exhaust manifold.

What year, model, and engine, and what gas are you using?
Ethanol gives me plenty of problems, which the better gas without corn usually doesn't. All gas boils much easier than the good gas of the 60's and 70's, so try to keep the fuel lines and carb as cool as possible. I made a heat shield for my 50 Champion, which helped a lot. I also added white plastic wire wrap over the fuel line from the pump to the carb. So far my 50 Land Cruiser is doing fine with no added shields.

[PackardV8]

Since the fuel system is plainly telling it doesn't like heat, but idles well when cold, consider blocking the intake manifold heat riser and removing the valve from the exhaust manifold.

For good measure, I add a cold air intake to the air filter.

jack vines

[DEEPNHOCK]

(For AFB equipped Stude and McKinnon engines)

Just installed one of these on an a/c equipped Avanti for a guy.
He loves the difference it made. (That and the gutted heat riser valve)

Edelbrock p/n# 8059

[Hawklover]

Jack I removed the heat riser, and inserted a block off spacer.

Since the fuel system is plainly telling it doesn't like heat, but idles well when cold, consider blocking the intake manifold heat riser and removing the valve from the exhaust manifold.

For good measure, I add a cold air intake to the air filter.

jack vines

[Hawklover]

Jeff me stupid.....when I swapped in a new Edelbrock 4103 (500 cfm) I not only cut off the bottom of the linkage to allow no interference with the intake runner, but I removed the top round hole portion of the linkage.....if I install this kit, I was told by the Edelbrock tech that the solenoid needs that portion (round hole portion) to hit up against.....now I have to figure how to fashion some kind of thin metal piece to allow the solenoid to hit up against.

(For AFB equipped Stude and McKinnon engines)

Just installed one of these on an a/c equipped Avanti for a guy.
He loves the difference it made. (That and the gutted heat riser valve)

Edelbrock p/n# 8059

[Hawklover]

Look here:

- - - Updated - - -

Look at this

[Jeffry Cassel]

Informative. This gadget appears to take the place of the dashpot. Bet it works.

[StudeRich]

So you removed the Choke heater Tube, but the exhaust is still heating the Carb. through the heat port.
Now the Choke and fast idle cam do not work without Choke heat.

Do you have A/C on your Truck?

[Hawklover]

Yes the tube is gone, but the carb has electric choke The heat riser has been removed and in it's place is a hollow spacer. I put several anti heat spacers under the carb. Yes the car has a/c

So you removed the Choke heater Tube, but the exhaust is still heating the Carb. through the heat port.
Now the Choke and fast idle cam do not work without Choke heat.

Do you have A/C on your Truck?

[TWChamp]

Informative. This gadget appears to take the place of the dashpot. Bet it works.

I only think of a dashpot as the device that slows the closing of the throttle for the last 1/4" or so of the arm.
There is also the vacuum diaphram used to raise the idle speed of an engine.

[64V-K7]

WOW....$165..

Two points to offer...
A) http://www.studebaker-info.org/64v24.../20090526.html - This dashpot was similar to the original / Bought it from Jon Myers in 2008 for around $50.00 / Works fine. / The car has an original A/C unit

b) That large round hole in the linkage was where this forum stated somewhere a while back, that was the preferred place to install the throttle rod. Summit has an insert that makes this easy... / I have no issues with my cars driveability

[Hawklover]

This was not the a/c speed-up assembly idle kit that Studebaker came out with for Avantis, (p/n 1563542) I had that and tossed it in the garbage because it never worked properly, and would never have worked with the Edelbrock clone carb.

WOW....$165..

Two points to offer...
A) http://www.studebaker-info.org/64v24.../20090526.html - This dashpot was similar to the original / Bought it from Jon Myers in 2008 for around $50.00 / Works fine. / The car has an original A/C unit

b) That large round hole in the linkage was where this forum stated somewhere a while back, that was the preferred place to install the throttle rod. Summit has an insert that makes this easy... / I have no issues with my cars driveability

[studebakerkid]

I would add a fuel return line. I have doen this wqhen needed and it makes a big difference.