Ye Old Vapor Lock vs Percolation

[greg g]

What is the condition of your heat riser.  If it is stuck? Operating correctly?

[mlozier76]

I seem to have these problems with the fuel boiling in the bowl after pulling a long grade in 90+ heat.  Unfortunately for me all roads to my house are up a fairly long grade, one with many stoplights.  I am going to try to address this issue with fuel tubing wrap, but I am planning to put a dual exhaust on my engine in the next few weeks, which may only compound my problems.  Last August had to sit at the top of  a hill for almost an hour after leaving a friends house at midnight because the fuel boiled to the point the car died.  I think it was still above 85 Degrees at midnight then.

[meadowbrook]

Thanks for all the responses!. By the way, my heat riser works fine and I do have the original pump shield.

I will lower the float to see what effect that has. Would it also cause my car to run leaner?

 

However, nobody really touched on the fact that it did start with a shot of starting fluid.

 

Would folks say that if the issue was percolation flooding the engine, then starting fluid would just worsen the situation?

 

If so then it sounds like the issue is indeed vapor lock, i.e. lack of fuel?

[Jeff Balazs]

Maybe? It has been my experience though that you can start almost anything with ether....as long as it is getting a spark.

Flooded or not it will usually fire and run for a while. Probably enough to get it past the flooded stage.....or for a iffy fuel pump to catch up with demand at idle.

Lowering the float level slightly....a couple of 64ths should not cause starvation or make it run any leaner. I would think that you should test this carefully to be certain all is safe after making this adjustment.

Jeff

[James_Douglas]

Anyone try running a fuel return back to the tank? Like use a Mopar fuel filter that has the return line connection on it. That would push the hot gas back to the tank. Would be best to install an electric pump with the fuel return. Install the return fuel filter right at the carb. Just pondering out load.

Earl

I did this on the '49 since I have the thing off the frame.  I am using a stock pump and have a boost pump by the tank.  I used a "T" at the carb that we welded the return side up then drilled a small hole in it for the bleed back to the tank.

 

James