Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

10hp Cast Iron Briggs has me stumped.


Orange

Recommended Posts

I'd appreciate any advice on my current project. Here are the facts. * I am trying to get a 10hp engine running in an old Landlord * I really don't know anything about the history of the engine other than it was supposed to have run well in the past. * It was given its last serious use about 4 years ago. * I installed it and it ran fine for about 5 minutes, shut it off. * Tried to start it a few weeks later and it was a bear to get going. * Ran very unevenly and sent out puffs of black smoke, tried to adjust the carb and got it going OK, ran it a few minutes. * Next time ran it and was hard to start, puffs of smoke, seemed to finally smooth out after fiddling with the carb. * Ran it yesterday, would crank it over and would fire, but wouldn't start right away, sent out generous amounts of black puffs. Finally got it going. Ran for about 10 minutes and sounded great then quit as I pulled into garage. * I checked the spark - none * Cleaned the points, spark again, started up fine and then ran for about 2 minutes before it started to run real rough, wouldn't run at full throttle, just barely chugged. * It then seemed to smooth out and ran strong for a minute, but then would chug again, fiddled with the carb some more, not help. * I've also changed the condensor with another, cleaned out two carbs &(installed), ,tried many plugs,checked to see if it was getting gas (it was) same result. * My questions and guesses are: Flywheel key is off a little Magneto is not working properly Points just aren't working I really am getting frustrated. If you have anything to try before I pull the engine, let me know. Thanks a lot and sorry about the long post. Please ask me any other questions if you need more info.
Link to comment
Share on other sites

thedaddycat
Have you cleaned out the gas tank to make sure there isn't any rust or something plugging up the fine screen as it draws fuel? Is the tank cap properly vented so that it doesn't pull a vacuum on the tank? If you have a spare gas tank from something else, try hooking that up and see what happens. I've heard it put that when looking at a smoking engine it's Black smoke fuel, White smoke valves, Blue smoke rings...
Link to comment
Share on other sites

It is more than likely a carburetor issue but I've found with old engines that have been parked a long time that the head gasket bolts are invariably loose leading to poor economy and issues with compression to get it started and running properly. Lots of times I've found some to be just off hand tight.
Link to comment
Share on other sites

You can throw out all that you "know" about the engine and start from scratch. First off, clean the carb. Make sure the jets and stuff in the carb are clean and flowing fuel unless you just kit it and replace the guts. Besides, that's the best bet. The crap in the gas they sell nowadays is a joke. Full of stuff that left sitting, will gum up or ruin small parts in these carbs. As they mentioned above, make sure you are getting a good flow of gas from the tank. make sure it's clean and that no trash is floating around the tank that would block the flow. This will give you great flow one minuet, and completely stop it the next. As for the ignition. It's hard to say what all might be wrong, but it's important to me to elliminate each thing one at a time. Start with the most obvious, Replace the points AND condenser. There are pages of documented problems from falty condensers. If your cam bearings are worn, then you may have to gap the points less than the orriginal specs. Worn bearings will let the cam push a larger gap than usual and keep the points open when running. If .20 don't run good, then back it down to .15 and retry. I wouldn't go below .10 Check all the wires that may be in contact with the secondary wire that controls spark kill. Disconnect the wires from the points goint to the switch and try. If vibration has caused some small short, simply removeing it from the engine will isolate it. A bad coil is not at all unheard of, but not very common. I wouldn't change it till last thing. Don't let the simple things that you "KNOW" shouldn't be wrong send you on a spending spree. Start with the most common thing and get deeper. Most of the time it's the little cheap things that we miss that cause the most aggrevating problems. Good luck, and if I've missed something I'm sure someone will jump in, Dave.
Link to comment
Share on other sites

Dave, You are probably correct. It sure gets frustrating though when the obvious doesn't seem so. I think the best thing would be to take a few days off and get back to it later this week. I will go through a checklist as you mentioned. I'll keep you posted. Thanks, John
Link to comment
Share on other sites

John, If all else fails, try checking the clearance on the valves. An exhaust valve with almost no clearance will present itself in the same way. I had a push mower that would start, make one pass across the back yard, then stop. I could re-start it and make one pass and again it would stop. I went through all of the usual things several times to no avail. Finally checked valve clearances, had none on the exhaust. A few strokes with a file and it ran beautifully. No more trouble.
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...