What is the issue with your auto choke Briggs. What is the engine model, type, and code?

Nothing fatal. Just a bit hard to start. Plus I was just thinking that things might be a whole lot simpler if I didn't have to worry with an air vane, spring tension on the vane, thermostat, etc.; in other words, more moving parts that can fail. Thusit is appealing just to be able to give the engine a few squirts from the primer and mow. I realize that the concept of "Ready Start" is an enticing homeowner marketing feature ... but how difficult is it to prime the engine once a week? T answer your question on the particulars, it is a '09 Toro Personal Pace with a Briggs as follows:

Quantum Model 120000

675 Series

126T02-0256-B1

Btw, my opinion so far is that a carb that is installed on primer engines, such as 799868 would likely work. Just exploring options.

http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=799868&_sacat=0

The auto choke system is not as forgiving if you are using older, untreated fuel. That is a given. The carb and the air box base is different. Or maybe one could update the old box w/ a primer, I dunno.

The auto choke briggs quantum usually has very good starting characteristics when the engine is cold. The carburetor is equipped with a smaller venture to improve fuel flow at slow rpm when the rope is pulled. Additionally, the ignition coil is designed to deliver a spark at slower rpm when the rope is pulled. These details are from the briggs update training a few years ago.

Starting problems usually occur when a cold engine is started and operated for about one minute and shut off. A few seconds later the engine is difficult to restart. The engine now requires the choke to be partially open or fully open. The thermostat has not sensed enough heat to react and the choke is spring loaded close. Pulling and pulling the rope continues to flood the engine with excess fuel.

If the cold engine is operated for 4 - 5 minutes and then shut down for a few seconds, the thermostat holds the choke fully open and the engine restarts easily. Briggs issued a bulletin a few years ago. On a cold engine, adjust the lever on the thermostat so that it is almost making contact with the air vane. This will improve thermostat response but unfortunately, the system is not perfect. Mowers operated at high altitude should be treated to the high altitude jet.

Some of the Honda auto choke engines with the thermo wax system experienced similar problems. The comment about old fuel applies. Fuel in your spare gas can deteriorate in as little as 30 days.

Great info, thanks. I can't help but think, however, that Briggs and the mower makers are utilizing Ready Start as more of a sales gimmick than a true technological breakthrough. As I have said before, how hard is it REALLY to push a primer bulb? Instead, there are a bunch of moving parts issues ... air vane position, thermostat, spring tension ... that have to be "just so" or problems creep in. In my case ,for example, the mower tends to lose RPM's sometimes. I set the idle speed with a tach to 3200 but before I am through mowing, I notice from the sound that the engine has slowed. So I stop and stretch the (new) gov. spring a little more by bending the tang ... a hassle. Could this be related to the vane not doing its job ... I dunno?