Sometimes, when I get ready to start our '27 and turn the key to batt, it will kinda chuff (like it want's to start) and turn the engine over a little but not enough to start. Any ideas what causes this?

(Message edited by Ken_Todd on August 03, 2015)

that sounds like it is a little too advanced and is firing BTDC and the engine is actually rotating backwards a bit...this will make a "chuff" sound...otherwise it's a normal firing of residual fuel...if it's a new engine, this is normal...if it's an old tired engine, it's compression and fit will be such that it would carry over and continue to run...newer engines are more prone to "chuffing" and old engines are more prone to starting.

A "free start" occurs when there's enough fuel/air in a cylinder to start the engine when spark is introduced and the engine stopped in firing position on that cylinder. When the key is turned to battery position the plug fires and off you go.

Sounds like you have all the ingredients present, maybe just not quite enough fuel/air to do the job.

Ken,
this is called a free start. It means you have gas in one cylinder, the piston is just over TDC and your ignition is set right to that point.
The chuff, like it want's to start and turn the engine over a little, means there if not enough gas in the cylinder to keep it running.
Just try this: prime your engine a few rounds, with choke pulled as the engine is cold without when the engine is warm, set the ignition lever all the way down, set on the contact and move the ignition lever slowly up. Now you should find a point where your engine start up without using the starter or the crank.
Works for me every other time I try.

good luck

andre
belgium

Watch the video of the start of the " Beast of Turin"
One man turn the engine till a certain point and stop, an other man set on the contact and the engine start right up. Set your computer load and you will enjoy.

http://theoldmotor.com/?p=133946

Andre
belgium

Holy #@$%!!! _Cranking that looks as scary as hand-propping an R-2800.

WOW! Now that is a beast! I love how the car kind of jumps in the air when the engine starts up.

just try this one too
https://vimeo.com/122644105?from=outro-embed

andre
Belgium

My 27 does the same and I put it down to the Vaporizer carby. I've found mine very hard to get a free start no matter what I try at best that chuff.
My 26 on the other hand running a NH Holley is the opposite.

Free starts are cool

The beast does seem to have a bit of an oil consumption issue.

At a fast idle retard the spark,count to 5 and turn off switch.It's hard to be exact because the speed needs to be right,the mixture/fuel charge needs to be right,you need a free clutch,you can wiggle the spark if needed to get a buzz,the engine has to stop in the right place,and if your trying to demonstrate a free one Lizzie will make you look bad!!! Bud in Wheeler,Mi.