Manual plus auto advance:what to do?

[John Gelfer]

I'm used to manual advance from driving a Model T. My '28 Gardner has manual advance, but also has centrifugal advance that kicks in at 650 RPM.

I normally start and run it with the manual advance fully retarded and leave it alone. Should I be advancing it after starting?

[Rusty_OToole]

You know how to use the manual advance on cars that had only manual advance. On cars that also have automatic advance the manual advance is used to adjust for different grades of gas and different road conditions.

Today's cheapest regular is higher in octane than 1928's best hi test. Once the engine is started you could probably advance it all the way and leave it there.

You can experiment and see what happens, if you notice spark knock on hills back off the advance until it disappears.

[John Gelfer]

I've never had overheating problems, like Model T's are prone to when running with a retarded spark, but I have had a lot of carbon on my spark plugs, and low fuel economy. Can running without sufficient advance cause these problems?

[nickelroadster]

You should play with the manual advance and try to set it where it seems to run the best. Yes, it is possible for these conditions to cause poor fuel economy and sooty plugs. To run fully retarded for the worst grade of gas is probably not where you want to be. If you still have sooty spark plugs then try the next range hotter plug, assuming that you are getting the car up to normal operating temperatures.

Edited September 26, 2010 by nickelroadster (see edit history)

[Rusty_OToole]

I'm no Model T expert but I thought you retarded the spark fully for starting, then advanced it fully for running.

[John Gelfer]

Yes, that's what we were saying...retard it for starting. The question was should I advance it after starting, since it has automatic advance anyway. I see the logic in what Nickelroadster was saying, and will try pushing the advance after starting.

[olympic]

My 27 Franklin has the centrifugal advance and the manual lever on the dash. I start it with the manual lever fully retarded and then advance it fully.

[John Gelfer]

Thanks for the help everyone. I originally thought I had carburetor problems, but it seems that "operator error" was causing the trouble. I will advance the spark after starting and see how it runs.