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New question submitted on 2008-12-05 by pa:
B&S lawnmover. Oil over filled, then mover would not start. Drained oil, removed sp plug and turned over engine. Cylinder pushed out oil. Dried plug and replaced. Still no start. What do I do next? tks, pa

Joe Says:
PA, Sometimes when an engine is overfilled with oil to the extent that it filled the cylinder, it takes a couple of times to clear out the cylinder before it will start(keep checking the spark plug). The other problem that could happen is that the oil could have filled the carb as well. If the carb is a diaphragm operated carb with an automatic choke, the the choke well vacuum chamber can fill with oil making the choke inoperative. The bowl on a float style carb can fill as well. You may want to try to prime the unit thru the intake to get it to run and then "nurse it along until it clears itself out. Remember when using anything flammable, to take appropriate precautions as not to start a fire. When you do get it running, it will smoke extensively for a time, in addition to filling the cylinder you also filled the muffler. This will take a while to burn out. Don't be alarmed at the amount of smoke that you will see, if you now have the engine filled to the correct level, it will quit after a while. Joe

New question submitted on 2008-09-22 by anonymous:
What would cause my lawn tractor to backfire when I shut it off. Does not do it all the time, but when it does it scares the heck out of me....

Joe Says:
Try letting it idle for a minute before you shut it off. When you shut it off the only thing you take away from the running process is the spark. When it is shut off the engine has a coast down time before it quit turning. It still intakes the air/ fuel mixture, compresses it, it doesn't burn it because the spark is turned off, then it exhausts it. This unburned fuel mixture is pushed into the muffler, if the muffler is hot enough it ignites it and thats where you get your "backfire". By idling it down before shutting it off you accomplish two things. First the engine coast time is less because its not running as fast, second the throttle plate is closed so we can't get in as much fuel. Hope this helps, Joe

New question submitted on 2008-09-22 by anonymous:
I have an old (1984) MTD with an 18hp b&s I/C. When changing the air cleaner I noticed it was wet. I ran the engine with the air cleaner off and watched gas spray up in the air from the carb at every rpm except W.O.T. What causes this? Thanks.

Joe Says:
With out knowing your model number, I can only assume that it is an opposed twin cylinder. There is a couple of thing that could cause this. The carb is not gravity fed, is uses a fuel pump incorporated in to the carb, so if the inlet needle and/or the float is not working, it will flood when running. The most common problem that we see that causes this is that the valve clearance is not correct. The correct clearance for an opposed twin is: intake .004 - .006, exhaust .007 - .009, cold, with the opposing cylinders valve springs installed. The possibility of valve leakage could also be an issue. A check and repair of these items should solve your problem. Thanks, Joe

New question submitted on 2008-09-22 by anonymous:
I HAVE A KOHLER CV186-61533 THAT HAS SUFFICIENT FIRE AND HAVE CLEANED CARB, IT IS GETTING GAS IN FUEL BOWL BUT THAT SEEMS TO BE AS FAR AS IT GETS. I PUT A LITTLE GAS IN CARB THROAT MANUALLY AND IT RAN A LITTLE, SOMETHING IS WRONG WITH CARB BUT I DON'T KNOW WHAT. HOW IMPORTANT IS THE SOLENOID THAT ATTACHES TO A JET IN THE BOTTOM OF FUEL BOWL.

Joe Says:
The following is based on the assumption that your carb has been cleaned and installed correctly. Your problem is definitely a lack of fuel issue. The solenoid in the bottom of the carb is to shut off fuel flow to the main jet. If it is not working correctly, you will have a problem such as you have described. An easy check would to be to listen for a "click" noise from it when the ignition switch is turned to the run position. If no noise is heard then either the solenoid is bad, the solenoid is sticky[can be cleaned], there is not power present at the solenoid when the switch is turned on or a bad gound preventing the solenoid from energizing. If your solenoid is working, and the fuel bowl is full as you stated, then the main jet has a restriction, it's the only thing between the fuel bowl and the carb throat. The fact that it runs when you prime it tells us that the compression and timing are sufficient. Hope this helped Joe

New question submitted on 2008-09-22 by anonymous:
I have a 72 model 8hp Briggs on a tiller. I replaced the points/condenser/spark plug and put a carb kit in that I got from you folks. I have a hard time starting it and then it quits before I can start to adjust the carb. It has good compression based on the fact is is hard to pull it over. I check the armature and it pegs on the ohmeter. I have all the gaps set according to specs. If I grab the plug and turn the flywheel I get a tingle so I think I have adequate spark. I even put a squirt of gas into the cylinder and tried to start it with no luck, it doesn't even offer. Any suggestions beside the BMFH treatment.

Joe Says:
Sorry for the delay, we were having some site problem. It doesn't sound like a hard starting problem, it sounds like a no start problem. An engine requires 3 things to run: adequate compression, ignition at the correct time and a correct fuel mixture. Compression should be checked with a compression guage, many things can make an engine turn over hard. A check with a guage will give you an accurate measure. Use an ignition tester to check for spark, if you dont have one, insert a screw driver into the plug wire. With the spark plug removed from the engine, spin the engine over with the rewind starter while holding the screw driver 1/4" away from the head. If the spark is good it will jump this gap. REMEMBER to use caution as not to ignite anything with the spark. If it doesn't jump this gap something is wrong with the ignition system. You can use an Ohm meter to check the coil if you know what your checking. You said it pegged the meter. What pegged the meter, the primary or secondary winding. When you say "pegged", is the circut pegged open or closed. Another thing is that if the flywheel mounting is not properly torqued, the flywheel key will shear putting the magnets in the flywheel out of time with the operation of the points, resulting in a no spark condition. If you check these first two items and have them functioning correctly, then you should be able to start the unit and set your carb. Hope this helps, Joe

New question submitted on 2008-09-22 by anonymous:
My snowblower starts fine and appears to run OK at lower RPM's but as soon as I set it to maximum speed the engine fluctuates from high RPM to midrange and back again. When it is under high load condition it levels out but doesn't seem to be at maximum power. I notice a link rod from the carburetor to a point on the engine block that has a pivot. This rod is fluctuating with the same rhythm as the engine.. is this a governor of some sort? .. and is this where my problem is at? I think I will be seeing you soon!

Joe Says:
I believe your problem is carburation. A lack of fuel issue exists. The Governor is looking for more fuel, thus the surging and lack of power under load. A good cleaning and kitting of the carb should do the trick. Thanks, Joe P.S. - We don't take in snowblowers until the end of September.