Hi, iam 16 yrs old an iam a aspring small engine builder and iam working on a 18 HP Biriggs V-Twin Vanguard for the family lawnmower. The problem is that when u start it up and mow for about 30 min. and if u stop it, it will never start up. So i went to the local B&S dealer i got a new magneto and a carb overhaul kit. Since i put the new magneto on it it will not turn over now? I charged the battery and did wat i thought was good. I dont know if taking the engine out of the frame was needed? So i herd of a (coil air gap) thing, and i dont know wat that is, so any suggestions is greatly appreciated.

Thanks alot

Hey im 14 lol, anyhow your coil air gap should be about .10-.14 inches, a simple way to set it is to put 2 peices of computer paper inbetween the coil and flywheel and then tighten down the coil bolts. You probably just have the coil jamming up the flywheel because the cap is to close.

yes, make sure that the coil is not sticking to the flywheel, you cacn se the card trick, or dollar trick. if this is a points/condenser magnetor check those too. and carb overhaul, did you adjust the fuel/air mixture right?

Thanks for the coil air gap information. And iam have not yet overhauled the carb yet, that is 2nites project. And for the points/condenser, could that prevent the engine from turning over? And when i tried to start it up the coil was not in contact with the flywheel, i put it as for away as i could cause the magnet on the flywheel was pulling the coil to it.

Thanks alot

yes, you definetely need the points, but you can take the condensers off, but then the points wont last that long. put the points on and look for a spark. if its pulling the coil toward it , turn it to a spot thats not magnetic and then do it. can of compressed air and carb cleaner will do =-)

Give me the engine numbers Model # and Code#

Being B&S Vanguard There should be no points and Condenser

true, but he doesnt know for sure :) :rolleyes:

Well i got the the coil gap set right and the top end of the carb overhauled, and supprisinly (sorry for spelling) the motor started up ever time and it sounds cool with no exhaust. The problem now is that i have to choke it out to shut it off??. And the #'s are CODE= 9410175A MODEL= 422707. The new coil instructions say that "if the engine is equipped to operate with an ingition breaker point and condender system, discard those parts" so my guess is that it does not have points and a condenser. And it helps that the engine to be grounded to start up?


Thanks Alot everyone!!!

And also when i give it gas it shuts off. I can keep it running if i press the choke in for about a second. I think that when i give it gas it runs out of fuel. Does it have to do with the air/fuel mixture or what? Any suggestions on how to fix it would be greatly appreciated.

Thanks alot!!!

Sounds like you didn't hook the kill wire back up, or it is broken..
That and the carb wasn't cleaned well... (code starts off 94, its a 1994 so no it has no points)
On the carb... was it torn apart and soaked well in a bath type carb cleaner? all the holes blown out well? Was there any screws on the carb.... it probably has no fuel adjustments except idle... all 1.5 turns out from all the way in snug then fine tune.

This has a Low Emmission carberator with oly idle speed adjustment. Did you install a new intake gasket under carberator? If not you may have an air leak. Hook the wire coming off the coil to the kill switch.

I still would like a code # its the number that follows the model #. It will be four digits like this XXXX-. Thanks for the model and serial #s

Without the engine numbers everthing is just a quess as to what parts were uses on your engine.

If you are going to learn small engine repair, look at engine numbers before you do anything. Those numbers are there for a reason and they will give you wealth of information when you learn where to look.