what's up w my non-starting lawnmower?

my push-type 6 hp craftsman mower won't start. last year i had the same problem and took it to be repaired; it worked fine for a few sessions then wouldn't start as per usual. sadly, in the meantime, the repair man passed away ...
anyway: i've put in a new spark plug and tested that it gets a spark, which it does. the fuel tube is unobstructeed. put in new gas. air filter looks good. took the carb bowl off -- it looked very clean -- and cleaned the holes in the nut (which were clean to begin with).
before taking the carb apart, i could spray starting fuel into the carb and get the mower running -- and it'd continue to run until i stopped it but wouldn't start again after that. after cleaning the carb, the fuel spray only succeeds in getting the engine to run for a second or two.
any thoughts? i suppose it's about time to take it to another repair person but i'd hate to admit defeat after doing so much.
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wrote:

The carb may have clogged jets. I've used a small wire plucked from a "wire brush" to clear the jets before. With the carb off you have to look for them. BTW don't break the wire off in the jet, be careful.
Oren
"My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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are you refering to the jets in the nut? if so, i've clean them. are there other jets that i don't know about and, if so, where might i find them? thanks!
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wrote:

Can't think of how to describe them other than them being "tiny holes" (look in the "tube"). I think they allow air in to mix with fuel. It is not the jet in the nut.
(The face is familiar, but I can't remember my name)
Oren "My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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Clear as mud. In the carb body, look adjacent/beside/behind the choke/throttle valves ("baffles"). There should be the holes I'm talking about. The only way I've found to clean/clear them out is with the wire from a wire brush. I use "stainless", not a rusted old brush. With a pair of needle nose pliers, grabbing the wire and cleaning out those holes. Do not break the wire off in there.
I wanna call them "air/fuel mixture" holes for some reason, just don't know the proper name.
Keep us posted.
Oren
"My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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I like compressed air to blow clear any jets. It wont enlarge the bore. Could also be a stuck float. This is a good time to get a carb rebuild kit and follow the directions carefully.
Charlie
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You stated that "before taking the carb apart, i could spray starting fuel into the carb and get the mower running -- and it'd continue to run until i stopped it but wouldn't start again after that. after cleaning the carb, the fuel spray only succeeds in getting the engine to run for a second or two." My old daddy used to say "If it doesn't work always check the last thing you did". Maybe you disturbed something, like the needle valve or float setting, when you had the bowl off. Recheck.

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John Lawrence wrote:

Or as my college electronics lab instructor was fond of saying 30 years ago, "If something smells, look where you cr@pped last."
Still applicable today, debugging hardware and software.
Jerry
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okay, i went to where i last crapped and redid everything and then it still wouldn't start. so i shot some fueling spray into the carp and opened the throttle and shot in more fuel and gave her a yank. up she started!
and she sounded pretty good, too. so i took her around the yard and back. i'm now letting her cool off and see if she'll restart. (I have my doubts.)
meanwhile, while running i'm getting a good number of popping sounds. what's that indicate? does that mean i should screw that little visible jet screw (right above the primer bulb) in or out?
thanks, all, for the help!
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wrote:

If your doubts are wrong and she cranks - tune it by ear. I rev the RPM and adjust the screw that way. I think the standard is to open the screw between 1 1/4 to 1 3/4 turns and adjust from there.
BTW what did you crap on?
Oren "My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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oren: well, i'm assuming i crapped on everything, so it's difficult to know which single crap was the culprit. but it does seem to be starting now, even when cold. huh. go figure! actually, the screw doesn't seem to make that much of a difference. sure, if i screw it all the way in, she revs up high, but once i back off about a quarter turn or so, there's this intermitant popping that stays at about the same level until i get the screw way out. my current plan is to just open the screw about a turn and a half and call it a day. what do you think? thanks again!
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wrote:

Adjust the screw "with" the engine rev-ed up. Your ear will help you tune the engine. The adjustment - IMO is a little different when the engine is under higher RPM. The best way is to see how she runs under a heavy cutting of grass. Good luck.
Oren "My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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Oren, I personally don't think you had a jet problem to start with. On a car this would be a fuel pump problem---same on the B&S engine.
If you took the carb apart you probably noticed a thin black rubber part that looked like a gasket. This part has two small flaps on the side that cover two holes on the carb. This is B&S's fuel pump. When they get old and harden they don't pump fuel through the carb like they should. When they saturate with fuel they get a little flexible to start, maybe, and cause the problems you have. This part is about $2 and I would surely replace it.
J
Oren wrote:

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actually, i'm not sure, but i think the engine is a tecumpsah. would it have the same flat as the briggs?
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wrote:

So you are going to take it to another repair guy and kill another guy. Have you no heart? Save the guys life and buy a new mower !!!!
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