Carb Problems

[55 Fargo]

Today went for a cruise today, went about 6 miles, but its cold around 5 above, the engine ran great, the temp gauge went up to about 165 during this run, but at 160 on this gauge is actually about 150 to 155 in the top of the rad, so it wasn't overly warm inside, a 180 t/stat would probably heat things up better, but my car isn't meant for winter driving, but the road is dry so why not go for a spin.

Here is another thing going on, after a bit of a run, where I am going about 40 mph or faster, and when I come to a stop, the engine idle is higher than what is normal for a warm idle. I just set the idle, and mixture a few weeks ago. When I turn off the car, it starts a bit hard, and seems slightly flooded, but clears it self quickly enough.

Throughout my ride the engine is running great, no hesitation, accelerates well, runs nice, but the darn idle is up when I come to a stop.

Is the float sticking, is it the accelarator circuit sticking or acting up, not sure what the problem is.

Checked the coil, it was slightly warm from the engine, but not hot, the starter motor was cold, the top of the head was slightly warm, but I could touch the engine all over with my bare hand, this is after driving 6 miles, goes to tell you how long it takes these engines to warm up in the cold.

I was having this problem last year, I want to correct this, and determine what the problem is...........Thanx guys Fred

[Merle Coggins]

Is there a fast idle cam connected to your choke like on later model carbs? It may be stuck on the high side.

I'm not familure with the automatic chokes on the cars. My truck has a good old fashion manual choke and throttle cable.

Merle

[55 Fargo]

I looked at the fast idle cam, seems to be in the normal position, the idle speed is up, but not like when it is in the fast idle position.........Fred

[Jim Yergin]

Fred,

Is there a return spring on the throttle linkage? Could it be weak and not bringing the throttle back all the way?

Jim Yergin

[Don Coatney]

If the ambient tempertature is five above zero, and your car delivered you back home after a short drive, what is the problem?

[55 Fargo]

No kidding Don, can you picture me pushing this boat down the gravel road, it is actually 2 above, thought it was warmer.Good thing there is winter here, I am sure if I lived in your climate I would drive the car just about year round, I can see this thing being driven daily, I am hooked on it..........

[55 Fargo]

Hi Jim, it is new, in fact almost brand new, just came in, had a look at the linkage, the fast idle cam and linkage, all is in nice clean shape, if there is a problem, it is possibly inside of the carb.

The carb was rebuilt by an experienced old car guy, about a year or so ago, but this problem happens all summer long also..................Fred

[48mirage]

Is there a leak in the intake somewhere. Maybe at the carb base, all of the screws tight on the carb, an air leak at the manifold to block area. Just reaching. I found the screws loose on my old Stromberg carb one time under with similar conditions. Tightened everything up and it worked much better.

[55 Fargo]

The carb screws are tight, but a leaking intake manifold migh cause this problem I suppose. After the block warms up, it might start leaking, you might not notice it when the engine is cooler.

I plan to take the intake off, and repair the heater riser, so maybe that will help..................Thanx Fred

[billwillard]

Adjust you r choke a little leaner. If it idled well a week ago when it was warm it should do so now. Adjust choke.

bill

[Rodney Bullock]

Fred, I applaud you for driving your car in -0 temps however you know that the car is going to compensate for the temp. If it needs a higher idle in the cold it's going to do it. Do you have that heat flap that's on the manifold? you know that flap and spring are controled by temp. If it is cold to the touch(motor) then it's not warm enough for that system to open. Even my cars idle is higher right now and when it gets warm..hot that flap is open 2 min after start up.

[Lou Earle]

Just to eliminate one source- attach another return spring and test again

Also when you stop can you pull the pedal back and stop the high idle? I sure sounds like weak return spring or a binding somewhere to prevent full return

Lou

[Rodney Bullock]

Fred, I applaud you for driving your car in -0 temps however you know that the car is going to compensate for the temp. If it needs a higher idle in the cold it's going to do it. Do you have that heat flap that's on the manifold? you know that flap and spring are controled by temp. If it is cold to the touch(motor) then it's not warm enough for that system to open. Even my cars idle is higher right now and when it gets warm..hot that flap is open 2 min after start up.

I went back and reread your post and you said it happens in the summer as well, That eliminates the heat riser. Do you have a thottle cable? some of our cas have a choke and thottle ( my 40 has both) if you have one look at it's cable to make sure the cable is not pulled back a little, it has to be an adjustment.