trouble getting full power: B/S 6.75hp lawnmower engine


Old 04-16-07, 08:40 AM
tzz is offline
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trouble getting full power: B/S 6.75hp lawnmower engine

last year it would only give about 30% engine power. let it sit. this spring i bought sparkplug and air filter.

now i get maybe 45% power.

i know nothing abt engines but i know i could clean some line out or carburator if i knew where to look or what to look for.

trying to save $ on a tune-up! only 2 years old. troy built self propelling mower from lowe's with briggs/s engine.

thank you if you have time to direct me.
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Old 04-16-07, 09:58 AM
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What did the old spark plug look like?
Have you tried new fresh fuel?
Old 04-16-07, 11:26 AM
tzz is offline
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this is what i did to fix problem but is it safe?

the old plug was blackened but not gunked up.

what i found was this:

took off the cover and discovered that the lever to give full gas-located on the opposite side of the engine as the cable that comes down from the pushhandlebar that cuts power when released-was not opening up.

this lever is directly behind the airfilter manifold and it has a tiny .02 cent spring that i guess should keep it open ...whatever reason it was not opeing to give power

i juryrigged it with a piece of wire and it stays open and cuts off safely when i release the powerhandlebar.

does this seem like a safe solution or am i harming the engine or possibly me>

Old 04-16-07, 08:59 PM
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This is unsafe as you suspected, since it basically disables governor operation. to fix you problem, remove the wire you put on it. Then, look at that small spring. One end connects to the carburetor linkage. The other connects to a hole in a tab-like piece of stamped out metal towards the front of the engine. This tab has been bent (probably by pushing the mower under some bushes or something). Bend this tab out towards the front of the engine a bit (increasing tension on the spring). The engine speed will increase more as you bend that tab out. The engine speed should be set around 3500-3600 rpm.
Old 04-17-07, 08:05 AM
tzz is offline
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thank you cheese. i will try that now. i knew it was unsafe but man i needed to cut the mini-baseball diamond in our yard!

thank you very much for the instruction. i will let you know how it turns out.

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