47 Roadmaster cutting-out uphill

[Guest sherlok]

Hi Guys,

I'm experiencing a problem when climbing rather steep hills of the engine trying to cut-out or stumble and almost quit until I get to the top. Runs great straight and level. I thought it was water in the gas, but I drained the tank and it still does it.

I'm now wondering if it might have something to do with the carburetor float. Anybody experience this?

Also who is a good carb rebuilder on the southeast side of the world.

Thanks,

Sherlok

Chattanooga, TN

[Pete Phillips]

This could be a lot of different things: weak fuel pump; dirty fuel filter; dirty or partly clogged pick-up tube inside the gas tank, or a small hole somewhere in the fuel line which prevents the fuel pump from pumping at its full strength. I think the key would be whether the car does this at any other time when the engine is working hard or near full throttle, and on level ground. Is the pick-up tube in the tank long enough to reach the fuel when the car is on an incline? Have the sending unit/float/pick-up tube been changed? If you are having to use this new gas with ethanol, the rubber fuel lines tend to break down if they have not been replaced since the mid-1990s. That could cause a small hole in the fuel line and decrease the strength of the fuel pump.

Pete Phillips, BCA #7338

[Guest sherlok]

Hi Pete,

Good points, but I have not used ethenol and nothing has been changed except the fuel filter in an attempt to correct the problem. Seems to just happen going uphill, but did not do this last year. I had not thought of a weakening fuel pump.

Thanks,

Sherlok

[Dave@Moon]

One quick thing to check is whether the nuts holding the carb to the manifold are tight. Often a hesitation during a specific motion can be traced to loose nuts that allow the carb to rock (due to the weight of the air filter) in one direction, in this case the carb would be leaning back towards the firewall. When that happens the vacuum leak caused by the seperation of carb and manifold/gasket would cause the "cutting out".

If it is loose, be sure to replace the gasket before you tighten the carb down for good. The rocking motion may well have damaged it.

This is more likely the cause if the car really does run well on level ground. If you can't reproduce the results by flooring the car on level ground for a long (but safe) distance, than this could well be your problem. Good luck! <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />