Loss of power while driving

[John Terrill]

I was driving my 1949 Dodge Wayfarer business coupe at 55 mph when the speed slowed to 35 mph. Stepping on the accelerator didn't increase the speed. But after 30 seconds the car resumed at a highway speed. It has happened twice. The carburetor has been rebuilt and the glass bowl in the fuel pump is clean. The car's odometer shows only 19,000 miles, but I'm sure it isn't 119,000 miles. The car runs fine, otherwise, all the gauges work as does the fluid drive. The car usually runs fine. I drove it home 100 miles the day before a snowstorm in November and it ran like a top.

[bobus8]

This is just a guess but the first thing that comes to mind is vapor lock since it seems to be ok in cold weather driving.  If it is this, make sure your fuel lines are not routed too close to exhaust pipe and not too close to engine.  If so, a simple fix is to wrap several layers of tin foil around the line in hot areas.  I don't know how old your fuel pump is but that might be the next thing to check.  Put a pressure gauge on it to see how much pressure it is producing.  

[soth122003]

Hey john,

 

You might do a visual on the tank and see if you have any small particulate floating around, then clean the lines, fuel pump, filter and carb. The ethanol in the gas can do a number with brown dust type residue if the car has been sitting for a while. (1-3 months).

 

Joe Lee

[pflaming]

On a drive with Don Johnson we had that problem. His problem was loose bolts on the carb bowl, four of them. Once tight all was normal. I constantly check those bolts. Will get new lock washers should help. 

[Bbdakota]

I've had similar experiences (with other cars) turned out to be restricted fuel flow. In my case the engine would die, tow it home and it would fire right back up,idle forever, 1 mile down the road it would die again. There was enough flow for idle and light loads on the engine but not enough flow to keep up at higher loads or speed. 

Some things to check if suspect fuel flow. 

Fuel filter clogged, on backward. 

Fuel lines for blockages or a pinhole on the suction side. 

Something in the fuel tank blocking the pickup. 

[1949 Wraith]

If you have one of those ceramic filters in a glass fuel bowl, I have heard that they can sometimes look clean, but actually be resticting fuel flow. If you have one remove it and see if that improves your issue.

[greg g]

Do you have the heat shield in place between the exhaust manifold and fuel pump??  What condition is your gas tank in??  There is a filter on the pick up that can get fouled with rust and restrict fuel flow especially at highway speeds.

Edited August 25, 2019 by greg g

[Don Coatney]

12 minutes ago, greg g said:

Do you have the heat shield in place between the exhaust manifold and fuel pump??  What condition is your gas tank in??  There is a fire on the pick up that can get foued with rust and restrict fuel flow especially at highway speeds.

 

 

FIRE?? Filter

[greg g]

Filter....  Heard the guy who invented auto correct died last week.  May he rust in pi$$.