VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt 28 burning way too Rich

28 is burning way to rich. Have checked the valves and clearances...all good. Any ideas?

skayhebert@aol.com

Sure...It.s your carburator

Cleaned the carb, reset the timing, cleaned the plugs started her up and every plug is fouled. Missing something fierce...Think the valve clearance may be the problem?

How is your float level?

I am 90% sure it is corrosion damage to the carburetor. I estimate that 9 out of 10 '28 carburetors have some damage. Some can be repaired and others not. I have rebuilt over 100 '28 Chevy carburetors in the past 10+ years. Many can be made to run adequately and a few very well. All depends on the condition of the main casting and the amount of money one wants to spend on a rebuild.

Float is 3/4 from the rim of the carb. The carb was rebuilt about 5 years ago. Funny thing is it ran great on Memorial Day. The Tuesday following memorial Day is when all the mess began..

The float should be 31/64" from the casting without the gasket in place.

Given that it ran well on Memorial Day, I suspect the condenser, points or coil in that order. I would first check the wiring to make sure nothing is loose or shorted. Then the points by open and closing them manually then shorting across them with a screwdriver. If you get a stronger spark by shorting, clean or replace the points. If there is no change, check to be sure that the condenser case is grounded and if so then change the condenser. If the case is not grounded then ground it and check the spark again. If nothing improves then consider the coil to be the problem.

Thanks Chipper will do..I shorted the plugs with a screwdriver as it ran today and had good spark at the plugs. will follow your advice and check the coil. I want to say that the condenser is the one that came with the car.

What spark plugs are you using? If not long reach Autolite 3077 or Champion W89D or similar then you will get incompete combustion. Also if you timing is too retarded you will get incomplete combustion. Exhaust restriction is another. You need to find what happened after Memorial Day.

Using 3777 plugs and have reset the timing dead on. I runs but it is missing with blue smoke at the exhaust because of too rich a mixture. Plugs foul easily because of too much gas in the cylinder. Timing is set dead on with points about to open on number one.

Are you running a vacuum tank or electric fuel pump?

If vacuum tank, take off vacuum line from pump to manifold and plug the hole at the manifold. Piece of duct tape will do. After running a minute or so does the smoke disappear and begin to run better? You should be able to run the equivalent of 4-6 miles on the fuel in the vacuum tank.

If electric fuel pump, shut off pump and see if the engine begins to run better after a really short while.

Generally "blue" smoke indicates a lot of oil in the combustion process. Black smoke indicates excess fuel and white (steam) in warm weather is generally a head gasket or cracked head. Steam in cold weather doesnt neccessarily mean any problem as cold moist air intake can be enough water to cause steam out the exhaust.
Tony