Timing question
 

I'm converting my ST G2300 to gas and was wondering about timing the EI. Does the magnet go top dead center? I understand that after determining TDC you rotate the crank to 28 degree BTDC (clockwise while standing in front of engine). This is where the hall sensor should be fixed, right? I've read numerous posts about timing but I was a little confused about the starting point of the magnet. It's mounted on the prop hub which can be rotated 360 degrees before I tighten it down.

RE: Timing question
 

If you can move the hub anywhere before tightening it down your all set.
Set the hall sensor at 28 degrees BTDC.
Then put the magnet on the left side of the hall sensor so you can see the whole magnet.
Just the outside edge of the magnet should be next to the hall sensor.[right side of magnet against left side of hall sensor.
Then check with a degree wheel and see for sure when the plug fires.
The hall sensor triggers after the magnet has gone past the sensor.
Go to chignitions for a downloadable degree wheel and instructions.Thats the man to see.

RE: Timing question
 

Where the magnet is located is not important. What is important is that the magnet moves past the sensor at 28 degrees BTDC. I kind of work backwards when I set my engines up. I find the most convenient spot to mount the sensor then find where the crank is at 28 degrees BTDC and mount the magnet at that point. Finding a good place to mount the sensor is sometimes more important than where the magnet is located on the hub as you can mount the magnet anywhere on the hub. Hope this makes sense.

Jim

RE: Timing question
 

Once the magnet and sensor are set, then how do I know when I have the ideal timing? Do I tach it until I get max rpm's or what? This is all new to me and sometimes the simplest questions are the hardest to find in these forums. I wish there was someone close that has some know how on electronic ignitions.

RE: Timing question
 

Go to[chignitions.com] and download the degree and instructions.
After everything is setup,you use the degree wheel with the plug installed in the boot,not the engine.
Then make sure the plug is grounded to the engine,then hook up your battery.
Then using a pointer,the degree wheel,you turn the engine over and notice at what degrees the spark plug fires.
First thing to do is go to chignitions website and look there.
Once yo read the directions,ect,youll have that AaaaaHAaa. moment.

RE: Timing question
 

I've read their instructions. That is why I asked the initial question about the magnet placement when the engine is TDC, it wasn't explained. But I do understand about the spark needing to be at 28 degrees BTDC. I'll just play with it until I'm the one answering questions instead of asking them. I've yet to install the magnet or the ignition. I'm waiting until I have plenty of time to engage the project without interruption. I may start on it this weekend. This is the same engine I posted over in the glow forum about flooding and running like crap, I got disgusted and gave up on glow fuel and decided to convert it to gas. I hope to have better luck this time.

RE: Timing question
 

Im going to send you a pm with the instructions from rcexcl.same as ch sells.Maybe that will help.

RE: Timing question
 

The bottom line is that it doesn't matter where the magnet or the sensor are placed, so long as they cross one another, and the spark occurs, at about 28 degrees before top dead center. The sensor can be placed any where convenient, and the spot on the hub for the magnet then chosen so that the timing will be right. Most sensor mounts then provide for a degree of fine adjustment to get the timing fine tuned just right to 28 degrees. Check your system to find out exactly when the spark occurs when the magnet crosses the sensor. Usually it happens just as the magnet is leaving the sensor after having crossed it.

AV8TOR

RE: Timing question
 

That makes sense to me, thanks.

RE: Timing question
 

Got my engine running today on the test stand. I played with the timing and got it pretty close. The problem I have now is with the carb. It's a walbro 414 I believe is a 13mm. It's flooding the engine and the only way to get it started is with an electric starter. I have to disconnect the pressure line to get it to run and as soon as I hook it back up it dies immediately. I think I need a different carb, maybe a smaller one. Any suggestions?
Also the engine is inverted and gas steady drips when its not running.

RE: Timing question
 

"pressure" line with a walbro carb? Is that correct? Do you mean your using a pressurized fuel tank with a walbro carb?

RE: Timing question
 

Simple sulution...un-hook the pressure line!!! :D

RE: Timing question
 

I bought a carb adapter from Ken Lambert which has a fuel line nipple on it. In the pics on his website the line is hooked up to crank case pressure to work the diaphram. My fuel tank is back on the CG so I need the carb pump. I know I'm doing something wrong, I just don't know what.

Since I have got off the subject, Ill stop here and do a search about troubleshooting walbro carbs.

RE: Timing question
 

Your plumbings riht in the pic.
\Crankcase line goes to the adaptor with supplies a pulse to the carb.
Tank line should go to black nipple.
If theres another nipple,block it off.
Vent from tank goes to where ever its not in the way.
In a plane i make one coll on top of tank,starp it down.Then i run the line out the bottom of cowl towards ground.
The only time a carb will drip fuel on its own is whe the needle and seat are stuck open or wrn out.
There under the cover with the 4 screws in it.
The pump is on the other side with 1 screw.
Get a different carb or reset the needle.Or take it to a repair shop.Or buy a new one.[from here on RCU or ebay].

RE: Timing question
 

There are a number of things that can cause a walbro to "flood". Buck mentioned a couple of items above that will cause the problem and also the rocker arm that moves the needle can get bent up too far and cause the needle to stay off the seat when the diaphragm and cover are installed. Like you said, do some research on the walbros and you will find a wealth of information. Also, the kit for these little fellows comes with a new needle, rocker, rocker shaft and many other parts including new diaphragms and they can generally be found for less than 10 or 12 bucks. My friendly neighborhood lawn mower shop sold me mine for $7.95. Good luck with the Tigre.

RE: Timing question
 

I solved the problem. Gas was dripping from the carb due to the needle not seating properly. I took it to a saw shop and got a kit, installed it and it did the same thing. You could set it in a cup of gas and blow air through the fuel line and the needle leaked like crazy. It must have had a bur on it because after pressing the needle hard and twisting a little it finally sealed up. The dripping stopped and it cranks and runs even with the crank case pressure line hooked up. It runs great now.