Small engine experience

I know this is a little OT, but there seem to be a lot of
knowledgeable small engine people in the group. My riding mower with
a Tecumsah engine has been giving me a lot of problems, quiting, rough
running and loss of power. I cleaned air filter, changed plug, and
checked fuel filter. I found I could get it to run by using choke,
increasing the choke level as fuel level in tank went down. So it
seemed to be running very lean.
Day before yesterday, I was mowing when I smelled smoke. I looked
around at my and neighboring houses- no smoke. I looked over to a
nearby wetland- no smoke. After awhile a light dawned in my brain and
I looked behind me at back of mower- smoke pouring out. It was coming
from around rear axle. I got out garden hose and wet down rear axle
area. There was a lot of grass piled up on top of rear axle, and also
mower deck, but not around engine. I had been keeping that area pretty
clean.
After cleaning away all the old grass around rear and mower deck I
restarted engine. I apparently overchoked it and it was hard to start,
but got it started with only slight choke. Then I found I could put
choke all the way in, and it runs fine. Good power is back. Glad to
have it running well, but the problem puzzles me.
So, what could happen in rear axle area or on motor deck with
collection of grass that would cause a front mounted engine to run
lean? Sure, the grass clippings could have put more drag on mower
deck or axle drive, but why would richening the mixture greatly
improve power. I would think that any mixture change away from the
normal mixture setting, when the engine was at operating temp, would
REDUCE power, not increase it.
BTW, I had previously ran two tankfuls through with a carb cleaner.
Reply to
Don Stauffer in Minnesota
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Yep, not a small engine, but my single-cylinder carburated dual-sport bike needed to be rejetted to run E10.
Dave
Reply to
spamTHISbrp
"Don Stauffer in Minnesota" wrote: (clip) So, what could happen in rear axle area or on motor deck with
^^^^^^^^^^^^^^^^^^^^^ Is it possible that grass was plugging up the exhaust?
Reply to
Leo Lichtman
My Tecumseh on my log splitter has the exact same issue. I thinks it varnish and crap in the carb. I richen it up by adjusting jets after its sat for a year. Then, after a few tanks of hard running, I lean it back out. Running the machine clear dry of fuel at shutdown seems to help. I've also used carb cleaner on it many times. Both in the fuel and down the throat.
My guess is you ran it extra hard with that bind up and burnt the cobs out.
Karl
Reply to
Karl Townsend
I recently helped my neighbor get an old push mower running. It would start, run a few minutes and then die. Nearly impossible to re-start then.
Problem turned out to be slightly loose head bolts. When I did have it running I had noticed the blow-by, but assumed it was coming from the muffler. Later on when I was scratching my head I noticed the muffler was good, no visible leaks where I had been seeing smoky exhaust.
Just an thought, something to check...
Reply to
Leon Fisk
Carb circuits are clogged. Pull the carb, get a kit for it and go though it. Use carb clean and compressed air on all the ports. JR Dweller in the cellar
D> I know this is a little OT, but there seem to be a lot of > knowledgeable small engine people in the group. My riding mower with > a Tecumsah engine has been giving me a lot of problems, quiting, rough > running and loss of power. I cleaned air filter, changed plug, and > checked fuel filter. I found I could get it to run by using choke, > increasing the choke level as fuel level in tank went down. So it > seemed to be running very lean. > > Day before yesterday, I was mowing when I smelled smoke. I looked > around at my and neighboring houses- no smoke. I looked over to a > nearby wetland- no smoke. After awhile a light dawned in my brain and > I looked behind me at back of mower- smoke pouring out. It was coming > from around rear axle. I got out garden hose and wet down rear axle > area. There was a lot of grass piled up on top of rear axle, and also > mower deck, but not around engine. I had been keeping that area pretty > clean. > > After cleaning away all the old grass around rear and mower deck I > restarted engine. I apparently overchoked it and it was hard to start, > but got it started with only slight choke. Then I found I could put > choke all the way in, and it runs fine. Good power is back. Glad to > have it running well, but the problem puzzles me. > > So, what could happen in rear axle area or on motor deck with > collection of grass that would cause a front mounted engine to run > lean? Sure, the grass clippings could have put more drag on mower > deck or axle drive, but why would richening the mixture greatly > improve power. I would think that any mixture change away from the > normal mixture setting, when the engine was at operating temp, would > REDUCE power, not increase it. > > BTW, I had previously ran two tankfuls through with a carb cleaner.
Reply to
JR North
Be aware that some of the carburetors used on Tecumseh engines have a neoprene seat in the inlet valve to the float chamber.
If you have removed the float and needle and then blow shop air through the fuel inlet port it I can practically guaranteed that the neoprene seat will disappear into the third dimension within milliseconds.
Don't ask me how I know this
Carla From the ashes of today's planning rises the Phoenix of tomorrow's fiasco.
Reply to
Carla Fong
The only Tecumseh I have (8HP) is on my '85 snow blower. I have had to take the bowl off the carb. on occasion and wipe moisture out of it. Now I add de-icer to every can of gas and run the engine every week, snow or no, during the season. In the spring, I run it dry, change the oil, put a couple squirts of oil in the cylinder and park it under cover. Come fall, I put in fresh gas and it starts on the second pull. Gerry :-)} London, Canada
Reply to
Gerald Miller
Greetings Carla, You have probably been asked this before but are you familiar with a bit done in a W.C. Fields movie involving Carl La Fong? Cheers, Eric
Reply to
etpm
But it runs FINE now. As someone else said, it might indeed be coincidence. I had been using carb cleaner in tank. Maybe just at the time of the fire the gunk just got dissolved :-) But since it runs fine now, I'll let it be for awhile.
Reply to
Don Stauffer in Minnesota

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