Idle drop

[M2116x6]

Our '28 has an issue with the idle that I have not been able to figure out. While driving, when you come to a stop it occasionally drops to a very low idle speed which will stall the car unless I move the column lever down quickly. Normally the lever is about 3 notches down for a nice idle. Most of the time this is fine but not always.

Yesterday I took it to a club show about 10 miles away. Ran great at 7am going to the show. On the way home mid afternoon it was well in to 90s and humid. About half way home the idle issue became worse. Coming to a stop it would want to shut off when I pushed in the clutch. By dropping the idle lever down there would be a delay and then the engine would rev up. It didn't want to idle slow and was difficult to keep running but I made it home. The temp on the radiator gauge during the ride home was right on the black horizontal line. Once home I let it cool down and changed the inline fuel filter which was dirty but not the sole cause of the problem. With time to cool down and the new filter, it ran better but still had the occasional idle issue. Could this be something with the float level?

 

[skip]

Interesting...Float level? Is what I read from many other posts on this subject. I'll wait for the answers to come in.

Checking the Les Andrews manual it says this about that..."Most carburetor problems are related to either dirt or rust in the jets and passageways, incorrect float level [relates to fuel level in the jets], or leaking gaskets."

skip.

 

[hardtimes]

I have a similar situation/problem. My '29 sport coupe (stock)will actually stall, but this happens ONLY when I have to jam on the brakes for a quick stop(otherwise runs great). Will be interested in comments, suggestions, ideas and possible solutions.

 

[Chris in CT]

Hi M2116X6, Your Idle mixture is too lean. Don't get this mixed up with the Gas Adjustment Valve on the choke rod. This is the needle valve located on the throttle tube just above the fuel bowl on the carburetor. With the engine standing at idle, screw the Idle Adjustment INWARD until the engine falters. Then back it off just enough so that the engine sounds OK again. If everything else is OK with the carb, i.e. no clogged passages or leaks, etc. your problem should disappear. Try this first, because it is very easy and may immediately fix your problem. Other solutions are going to require more time-consuming proceedures. Happy Motoring!

 

[Patrick L.]

It seems to me that the idle speed should be set at the throttle stop on the carburetor, not at the steering column.. I too would set the idle mixture before looking at too much else[ cuz its easy].. With the engine warm and at a proper idle speed turn the mixture adjusting screw in [CW] until the engine just starts to falter, then out[CC, and the engine will speed and smooth up] until it again falters, then split the difference and the engine speed will pick up and run fairly smoothly..It you're going to err, I'd err on the rich side..The spark lever should be at full retard, but, I don't think it makes a whole lot of difference..