1935 Ford coupe driveabilty problem

[Firepower flyer]

Hello fellow Barners
I need some suggestions on what could be causing a problem with my coupe,only under load. If you drive very easy and slow it's fine but as soon as you load or give it some rpm the engine it starts to run very rough and shake and surges and feels like it's missing, but it's only under load. If it's in neutral and revved up it's fine. The car is a original paint survivor that for the most part has always ran and drove fairly nice. The condition of the engine is unknown, as I said it's always ran fine but it is tired. This is a new problem the car used to run decent. I rebuild the carb and fuel pump with parts from Charlie and the condition is still there. The distributer was rebuilt years ago and I have not looked into that yet. I will say it's always started ok when cold but is pretty dam stubborn when it's warm. Any thoughts would be appreciated.

[Jembow]

Electrical breakdown under load. Coil? Points? Condenser? Dirty connections? Frayed wire? Cracked cap? You need to check through all these. Do you know anyone can loan a known good distributor to swap?

[ford38v8]

The rebuilding of a carburetor with known good parts is incomplete until it is adjusted and tuned to the engine it is installed on.

[Planojc]

I would start with a new condenser.

[Firepower flyer]

Originally Posted by ford38v8

The rebuilding of a carburetor with known good parts is incomplete until it is adjusted and tuned to the engine it is installed on.

The carb has been tuned and adjusted, not that there's a whole lot to do to them. The problem was there before and after so I fairly certain it's not the carb but more of a electrical issue.

Originally Posted by Jembow

Electrical breakdown under load. Coil? Points? Condenser? Dirty connections? Frayed wire? Cracked cap? You need to check through all these. Do you know anyone can loan a known good distributor to swap?

I don't has access to a spare distributer but I will pull it off and have to look it over, if not I'll sent it off to Bubba.

[rotorwrench]

Sponsored Links (Register now to hide all advertisements)

Do the easiest thing first in troubleshooting and go from there. Easiest thing to check is always the condenser. The more load on an engine, the more the engine compression load changes. This has an effect on ignition spark. The condenser has an important control over how the ignition coil induction process happens as well as prolonging the life of the breaker points. If its capacity drops off or it leaks then the ignition function will deteriorate. Same thing goes with a questionable coil or other high tension transfer components already mentioned.

Another possibility is if something is plugging off flow inside the gas tank or if the venting isn't working for the tank. If the tank is clean inside and properly venting then there should be no issues.

[blucar]

Originally Posted by rotorwrench

Another possibility is if something is plugging off flow inside the gas tank or if the venting isn't working for the tank. If the tank is clean inside and properly venting then there should be no issues.

An un-vented fuel cap is a very common problem on vintage vehicles, causing a lot of problems. That would be the first thing I would check before I started to RR parts from the ignition.
If the fuel cap is an old one the vent in the cap might be compromised from age.

[richard crow]

what carb are you using does it have a power valve