# Tecumseh 5 HP Snowking Snowblower



## Bob DiGiacomo (Jan 15, 2009)

Hi guys I have a 5 HP snowblower Craftsman 143.975001 that is dying under load. I cleaned the carb, then bought a new carb, still the same problem. Compression is 140psi, I can adust the bowl needle until there is too much fuel and also not enough fuel, but it still dies under load. I adjusted the tension on the springs not much difference. I replaced all the fuel lines, switched the fuel cap, cleaned the fuel tank screen, changed spark plug, cleaned coil contacts. When I got the unit it was overfilled with oil and once I tested it out the extra oil came out the valve cover reed. I don't know what else to look at. Maybe the governor is stripped? Thanks for any help.


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## Sir Thomas (Dec 7, 2013)

Bob DiGiacomo said:


> Hi guys I have a 5 HP snowblower Craftsman 143.975001 that is dying under load. I cleaned the carb, then bought a new carb, still the same problem. Compression is 140psi, I can adust the bowl needle until there is too much fuel and also not enough fuel, but it still dies under load. I adjusted the tension on the springs not much difference. I replaced all the fuel lines, switched the fuel cap, cleaned the fuel tank screen, changed spark plug, cleaned coil contacts. When I got the unit it was overfilled with oil and once I tested it out the extra oil came out the valve cover reed. I don't know what else to look at. Maybe the governor is stripped? Thanks for any help.


The Govenor adjusts the throttle thus the engine speed according to load. A weak spring usually causes a surging in the motor. If you can, watch the governor links when the motor is under load to see if it moves. Usually is will throttle up to adjust for the load or it could be over compensating and flooding the motor. If it doesn't move at all there either something wrong with the arm or the linkage or worse yet internally.

Go to this link, about half way down the page on the link it talks about the governor.

http://www.scribd.com/doc/26830208/Tecumseh-Service-Manual


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## Bob DiGiacomo (Jan 15, 2009)

Thanks for the help. Thanks for the manual link. I see the gov arm trying to throttle up, but it is dying like not enough fuel or too much fuel? I read in the manual to look for proper valve lash, but I'm thinking how can the valve lash be off if the compression is 140psi, but I'm not sure? I'm thinking maybe the valves are not opening far enough? Not sure what exact engine I have so, could you tell me the valve lash? Muffler may be blocked (I can check this easily). Should I investigate the valve lash?


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## geogrubb (Jul 28, 2006)

Bob DiGiacomo said:


> Thanks for the help. Thanks for the manual link. I see the gov arm trying to throttle up, but it is dying like not enough fuel or too much fuel? I read in the manual to look for proper valve lash, but I'm thinking how can the valve lash be off if the compression is 140psi, but I'm not sure? I'm thinking maybe the valves are not opening far enough? Not sure what exact engine I have so, could you tell me the valve lash? Muffler may be blocked (I can check this easily). Should I investigate the valve lash?


I would suggest adjusting the governor setting before doing anything, the procedure for setting it is on page 27 of the link Thomas provided. Have a good one. Geo


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## Bob DiGiacomo (Jan 15, 2009)

I preformed a static gov. adjustment as well. It was set correctly, but thanks for the suggestion.


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## dehrhardt (Apr 1, 2009)

First check to make sure the snowblower mechanism isn't bound up. The engine can't move it if its resistance is more than the power output of the engine.

If it isn't bound up, I would check the governor linkage. I know you did a static adjustment. Did the throttle go from fully closed to fully open smoothly, with no binding? With the throttle lever set to fast, and the engine off, the throttle should be wide open and the throttle spring holding it there pretty firmly.

140 seems high for a small engine with a compression release. Though I don't see it often, it couldn't hurt to make sure the muffler isn't plugged or restricted.


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## Bob DiGiacomo (Jan 15, 2009)

Thanks I will check those few things out. But quick question. Can Hi compression be caused by the wrong size valve clearance?


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## dehrhardt (Apr 1, 2009)

A high compression reading can be caused by improper valve lash. Having said that, I must further add that small engine companies don't publish compression figures because most of their engines have a compression release. At low speeds, the compression release relieves some of the pressure developed during the compression stroke of the engine to allow for easier starting.

A "normal" compression reading for a small engine with compression release would be anywhere from 50-80 psi depending on the design and wear. Normally with L-head engines, (such as your Tecumseh), the lash decreases over time as the valve wears into its seat. If you could do a compression test with the engine at operating speed 140 wouldn't be high. I said 140 was high because with a functioning compression release, you would not see a reading that high.


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## Bob DiGiacomo (Jan 15, 2009)

Thanks for the info. I got the compression reading using the electric starter that may be why it is so high. I checked the flywheel key it is good, and I ran it with the muffler off and it had the same symptoms. I pulled the head and everything looks good there, I guess I will check the valve lash at this point. The snowblower is not binding or anything like that, in fact it throws the snow really far. Where should I look from here?


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## dehrhardt (Apr 1, 2009)

The only other things I can recommend would be to use a spark tester to check for spark. Spark testers have a wider gap than plugs so that any weaknesses with the ignition system show up.

If your valve lash is below spec, as the engine heats that valve won't be able to close fully.

After you check valve lash, note whether both valves are being lifted about the same. A wiped cam lobe will also cause a low power condition. Good luck and let us know what you find!


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## Bob DiGiacomo (Jan 15, 2009)

I tore the whole thing apart and found the valve clearance was zero, so I ground the valves and put everything back together. When I tried to start it kept stalling like it was starving for fuel. I played with the carb adjustment screws for about 5 minutes then I noticed a fuel leak at the tank side of the blower. The brand new fuel shutoff valve was leaking fuel at the red valve, but it was also letting in air and screwing up the fuel mixture. I replaced it and it worked excellently. I think the new fuel valve was the main problem, but if I would have left the valves the way they were they would not be closing properly in a year or so.

I have another question. I have a similar Murray 5hp tecumseh that only throws the snow 8 feet. It looks identical to the craftsman as far as auger, chute, and engine. The craftsman throws the snow 25'. The belt on the Murray looks like it fits nicely, but maybe it is slipping? I gave my Dad a murray 7hp and we replaced his belt and it did nothing as far as making it throw snow further. So I don't know if buying a new belt will help. What should I do? Thanks again. Bob


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## dehrhardt (Apr 1, 2009)

Congratulations on your success!

On the other blower i would suggest checking the belts to see if they are the right type, (could be the wrong width). Also possible the pulleys are worn if this is an old unit. Make sure the deflector at the end of the chute isn't closed down too far. The direction of the chute will often affect hoe far the snow is thrown. Beyond that, I can't help you.


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