Smoking muffler with gas and oil leaking out.

[Chris P]

Hello all.
I have a 42 inch deck poulan pro mower with a 19 HP Briggs 33r877-0009 engine. The tractor was starting hard to the point where I really couldn't get it going. I figured it was probably a bad carb so decided to replace rather than rebuilding it. I installed the new carb (aftermarket from Amazon) and i still couldn’t start it. It seemed like it wasn’t getting great compression. So I installed a new head gasket. I Torqued it down to spec. This definitely improved the compression. I Set the valves to their specs and changed the spark plug with an oem one and replaced the oil filter and did oil change. I got it started but the muffler is smoke badly and getting hot. Adjusted the carb.. no change. I checked the valves again. They were still in range but I gave them a slight adjustment. same situation. I then put the old carb on. It ran great for a minute. Stalled out. And I noticed smoke coming from the muffler and a slight bit of gas dripping. I pulled the flywheel cover off and removed the nut thinking it might be a timing issue. the key was in line. Running out of ideas. Any suggestions would be appreciated greatly.

 

[DaveTN]

Hello and Welcome to the LMF! Sounds like you know quite a lot about mowers having
done all those things. Wondering how it ran before it started giving trouble? With the old
carb on it you say it ran for a minute then stalled? Could possibly be fuel getting into the
oil and causing a very hard start as well as bogging down. What is the oil level like? Does
the oil have fuel in it? Fuel in the oil would cause smoking all the time. Just something to check.

 

[hlw49]

You have said a lot of stuff like a politician and not said what it was doing. Or better yet what if wasn't doing. Won't start why? Not spinning the engine over spinning over but would not start? Muffler running hot compared to what? Mufflers do get hot because of the heat of combustion. Saw smoke coming from the muffler and a small bit of gas dripping from where? Carb or muffler? Or is the valve cover leaking oil onto the muffler and the oil smoking when it drips on the hot muffler? If it will not crank over and kicks back on the starter it is probably the compression release. Or cam lobes slipped on the cam shaft.

 

[Rivets]

I’m guessing the carb needle valve is not closing the and you are getting an extremely rich running condition, plus if you pull the dipstick you will smell fuel which will indicate contamination in the oil. Solution, clean and rebuild the carb, plus change the oil.

 

[Chris P]

Hello and Welcome to the LMF! Sounds like you know quite a lot about mowers having
done all those things. Wondering how it ran before it started giving trouble? With the old
carb on it you say it ran for a minute then stalled? Could possibly be fuel getting into the
oil and causing a very hard start as well as bogging down. What is the oil level like? Does
the oil have fuel in it? Fuel in the oil would cause smoking all the time. Just something to check.

Hey Dave! thanks for responding. I do suspect there is some fuel getting in the oil. The oil level hasn’t increased from what I can see. I do get a faint smell of gas from the dipstick. Previously it ran great once it got started. What puzzles me is that with both carbs I’m getting the same result which makes me think the problem is deeper.

 

[Rivets]

Personally I have learned to never trust the aftermarket carbs on Amazon. Most times they are advertised to fit many engines, which they do, but because they are made to fit multiple engines the jetting doesn’t match the OEM carbs. I’m still inclined to go back to clean and rebuild the original carb.

 

[Chris P]

You have said a lot of stuff like a politician and not said what it was doing. Or better yet what if wasn't doing. Won't start why? Not spinning the engine over spinning over but would not start? Muffler running hot compared to what? Mufflers do get hot because of the heat of combustion. Saw smoke coming from the muffler and a small bit of gas dripping from where? Carb or muffler? Or is the valve cover leaking oil onto the muffler and the oil smoking when it drips on the hot muffler? If it will not crank over and kicks back on the starter it is probably the compression release. Or cam lobes slipped on the cam shaft.

Let’s dissect your response.

You have said a lot of stuff like a politician and not said what it was doing. (This one just puzzles me) Or better yet what if wasn't doing. Won't start why?(I stated initially I thought the carb was bad and that’s why it was starting hard. And if I knew definitely why would I bother with this question) Not spinning the engine over spinning over but would not start? Muffler running hot compared to what?( obviously the point of reference would be the normal temp it ran at previously.. I think it’s clear this isn’t a new tractor)Mufflers do get hot because of the heat of combustion.(duh) Saw smoke coming from the muffler and a small bit of gas dripping from where? (Think it’s pretty obvious I was referring to the muffler from the context. If you couldn’t put those dots together maybe my title which was “Smoking muffler with gas and oil leaking out” could help you out) carb or muffler? Or is the valve cover leaking oil onto the muffler (really. In a matter of 1 minute I wouldn’t notice that when I mentioned twice I adjusted valves) and the oil smoking when it drips on the hot muffler? If it will not crank over and kicks back on the starter it is probably the compression release. Or cam lobes slipped on the cam shaft. (Ok these last ones are possible solutions which was the purpose of my question.. and I do thank you for that)
Seems to me you’re the politician by spending more effort on personal attacks and your agenda than trying to help with the solution. FYI

 

[bertsmobile1]

Well I will put it this way
Rivets & Myself make our living from fixing mowers
Like him I only fit carburettors that come from certified wholesalers and should have been subject to some quality control so 99.99% of the time they will be good .
OTOH I repair or replace at least 20 carbs that owners had bought from ebay & amazon.
There is a good reason why they are so cheap & it is not price gouging from dealers .
Your symptoms co-relate to those attributed to a failing carburettor float, a problem I see every day at the beginning of the season.

Some one else put forward an idea I had not thought of but was good
Loosen the carburettor mounts and slide the carburettor back 1/16"
If the float is failing fuel will drip from the gap .
The volume of the drip will be determined from the magnitude of failure .

Chronic leaks will end up diluting the oil

Similar symptoms can occur with a failing head gasket between the cylinder & pushrod tubes
A stuck or failing breather valve can also cause similar symptoms .

Then your description of your symptoms will not necessarily be my description of the same symptoms .
We are here to help
Attacking those here offering good advice will do nothing more than cause others to ignore you

 

[VegetiveSteam]

Hello all.
I have a 42 inch deck poulan pro mower with a 19 HP Briggs 33r877-0009 engine. The tractor was starting hard to the point where I really couldn't get it going. I figured it was probably a bad carb so decided to replace rather than rebuilding it. I installed the new carb (aftermarket from Amazon) and i still couldn’t start it. It seemed like it wasn’t getting great compression. So I installed a new head gasket. I Torqued it down to spec. This definitely improved the compression. I Set the valves to their specs and changed the spark plug with an oem one and replaced the oil filter and did oil change. I got it started but the muffler is smoke badly and getting hot. Adjusted the carb.. no change. I checked the valves again. They were still in range but I gave them a slight adjustment. same situation. I then put the old carb on. It ran great for a minute. Stalled out. And I noticed smoke coming from the muffler and a slight bit of gas dripping. I pulled the flywheel cover off and removed the nut thinking it might be a timing issue. the key was in line. Running out of ideas. Any suggestions would be appreciated greatly.

I've pretty much only worked with Kohler and Tecumseh engines for the last 26 years so I have to plead a bit ignorant on Briggs but, for the flywheel does Briggs use a straight key or a woodruff key? If it's a woodruff key then to be sure the key is not sheared the flywheel will have to come off. Also, if this engine has a pulse style fuel pump check the pulse line for fuel. If there is fuel there, you need a new pump.

 

[hlw49]

I've pretty much only worked with Kohler and Tecumseh engines for the last 26 years so I have to plead a bit ignorant on Briggs but, for the flywheel does Briggs use a straight key or a woodruff key? If it's a woodruff key then to be sure the key is not sheared the flywheel will have to come off. Also, if this engine has a pulse style fuel pump check the pulse line for fuel. If there is fuel there, you need a new pump.

Straight key.