# Tecumseh engine



## danjb (Aug 3, 2010)

I have a Tecumseh engine. I use it for forest fire protection so it gets used almost zero. When firing it up this summer it took considerable work to get it started. Now it started runs several minutes (3 to 10 minutes). Then quits. Befor it quits it suddenly begins to struggle but you can rally it by playing with the choke, but eventually it quits. The spark plug is black, dry and suitty. I have gapped and cleaned it. I have cleaned the carburator several times. I noticed fine particles of gas sputtering out the air filter hole (when air filter was removed). Any suggestions?


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## K-B (Oct 24, 2005)

Hi, welcome to TSF.

It sounds like its starving for gas. If it has a fuel filter, you could try replacing that. If possible, try to look inside the tank with a flashlight and check the fuel outlet for any debris possibly plugging it. This can be difficult or impossible depending on the fuel tank configuration. Another possibility is the fuel cap, that would be a vented cap and if the vent is not working properly it will cause vacuum in the tank and will quit running. Try removing the cap after a few minutes and see if it continues running.


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## danjb (Aug 3, 2010)

Thanks for your response. There is no fuel filter. I've now taken the gas tank off and cleaned thoroughly. The vented gas cap seems to work... same result if I take the cap off when it is running. I'll get a new spark plug today and try that, though I don't think that is the problem. Just running out of ideas of what else to try.


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## TheAlSmith (Aug 4, 2010)

In venacular terms, it sounds like your unit just needs a tuneup but there may be more to it. What is the compression of your engine? Can you see the valves moving freely? If it is spitting fuel out of the intake it is getting too much fuel. So why then is it not going into the cylinder and burning efficiently? :4-dontkno

Since your spark plug is black, dry, and sooty, you obviously have a great deal of carbon in the cylinder. In this case, it would be advisable to remove the head and clean the head and pistion top. Carbon may be holding a valve open or be built up on the valve stem causing it to stick from time to time. :idea:

Another thing I would do prior to this is put an inline spark tester on your spark plug and watch it while the unit runs. Maybe your Ignition Module is overheating and cutting out on you and that is why you have so much carbon and the unit is stalling out no matter what you do. Cleaning the fuel system and setting up your carb properly is definately a good idea but it may not be the solution. I have seen many times where even an experienced technician chases a fuel problem and doesn't notice that it is the Ignition Module at fault. :sigh:

Checking the fuel cap was a great idea but since you now know that isn't the problem continue searching for other possible issues. We know the unit will run so now we need to know why it stops even with the choke on. Leave the fuel system for now and check the spark. I would definately put a new plug in it but since that didn't solve your problem (are you sure you didn't get a bum plug? I happens.) look to the module and see if that solves your issues. :wave:

Al


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## danjb (Aug 3, 2010)

Al,
Thank you for the input. You gave me a lot of info and stuff to do. I am going to pursue your directions.
Dan


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## tg3234 (Dec 23, 2010)

Tecumseh engine: I'm trying find out if this 5 hp engine has a alternator. It's a older engine which is used on a AMF Husky snow blower. It runs great. What I have is one black wire that runs behind the gas tank and is attaches to a metal clip that is attached to the engine located along side the head. Don't know if this is some type of ground. Any help thanks. I have pictures and will try to attach.


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## K-B (Oct 24, 2005)

That is the kill wire.


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## tg3234 (Dec 23, 2010)

Thanks for the response. I'm guessing a kill switch could be attached to this wire.


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## K-B (Oct 24, 2005)

Yes it was usually used for a remote safety key or on/off switch.


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## tg3234 (Dec 23, 2010)

Do you think it would be possible to run a light of this wire?


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## K-B (Oct 24, 2005)

tg3234 said:


> Do you think it would be possible to run a light of this wire?


No. There is no power in that wire. The only way you could run a light is if the engine is equipped with an alternator. If you remove the engine cover, you can see if there are any wires running under the flywheel (the alternator would be under the flywheel).


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## tg3234 (Dec 23, 2010)

thanks for the response and info, happy holidays.


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