Briggs engine was smoking bad....

mark abby

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27hp Twin B&S #446777 2441

i read some posts in here about engines smoking on a hill, and mine was doing that...so i thought. The suggestions given were that thee head gaskets were probably bad. So, I began the %$#@%$@# of removing one of them, and thee head gasket was great. However, i brought the piston up to the top of the cylinder and i could jiggle it back and forth. I wasn't sure if that was normal or if I just have bad rings. (ugh) So, is the side to side movement normal for a piston?

This Poulan garden tractor was bought back in 2006 and it's been a great mower. I'd hate to throw it out because it's still in great shape. Last year I did a compression test and it was just over 100# if i remember right. Other than smoking real bad, it ran great and really didn't lose power cutting.

Like i said, i only removed one head, should i check the other as well before i scrap the motor? I don't have the tools or time for rings.

Opinions? Suggestions?
 

SeniorCitizen

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The oil use problem can be connected to the good compression reading . There may be mower mechanics here with tolerances of wear .
 

Rivets

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There are multiple things that can contribute to smoking from a small engine. Blown head gasket, worn cylinder and/or bad rings, oil level too high, due too fuel filling the crankcase, breather not working properly, rich running engine, etc. The color of smoke can give you a starting point where to look first. Blue smoke is normally an indication of oil consumption. Black smoke an indication of a rich ruling condition. White smoke is normally water in the fuel, but on a small engine I’ve seen white smoke when a unit is run on a slope where excess fuel and oil get sucked in together.

You need to do some more research and get back to us for more help. Check the plugs, what do they look like. Black sooty plugs indicate a rich running condition. Oily plugs mean oil getting into the cylinder. May be one or both cylinders. Causes may be blown gaskets, worn cylinder or rings, high oil level. After you are able to do more research let us know what you find.
 

mark abby

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I pulled the left side head off. it was loaded with thick carbon and the exhaust valve appeared to not be seating fully. I did a compression test on the opposite cylinder and my gage showed a steady 120 psi and held it there.

so, i cleaned the head of all carbon and i want to replace the valve seals....however, looking at B&S parts diagrams they don't show the exhaust seal that was in mine, the one i pulled out had a rubber tip on it, whereas the intake one is just a cap with a rubber seal. Looking on line, they show exhaust guides some have the rubber ring while other don't. Whats up with that? I'm not sure if they are the right ones for my engine.
 

bertsmobile1

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Exhaust blows and inlet sucks
So most mower engines just have a seal on the inlet valve as that will suck oil into the cylinder & blow smoke .
 

Tiger Small Engine

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Exhaust blows and inlet sucks
So most mower engines just have a seal on the inlet valve as that will suck oil into the cylinder & blow smoke .

The play in the piston (slight back and forth when pushing it with fingers), is most likely worn connecting rod bearings. We are talking about an 18 year old Poulan riding mower that is smoking. Check color, amount, and when it is smoking while running. Keep an eye on the oil level every time you use it, top off as needed, and run it. You say it is smoking a lot. Is it smoking like a freight train constantly? If so, it is just a matter of time before she gives up the ghost.
 

mark abby

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Exhaust blows and inlet sucks
So most mower engines just have a seal on the inlet valve as that will suck oil into the cylinder & blow smoke .

ok, but my question is the exhaust guide I removed had a rubber insert in it, and all the ones I have found don't seem to have that. I understand what you're saying, but, was this a design change for that motor? I even emailed B&S and asked, but they were of no help. The intake seal was easy to find. The parts diagram doesn't show that damn guide...at least the ones i'm looking at.
 

StarTech

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Not able the model/type number you posted please double check.

But normally nothing is insert in the exhaust valve guide other the the exhaust valve stem. Kawasaki is about the only one that uses seals on the exhaust.

Now as for the piston movement that is not normal. And it is probably the #2 cylinder which I have seen worn ovaled on several Briggs V-twins.
 

mark abby

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Not able the model/type number you posted please double check.

But normally nothing is insert in the exhaust valve guide other the the exhaust valve stem. Kawasaki is about the only one that uses seals on the exhaust.

Now as for the piston movement that is not normal. And it is probably the #2 cylinder which I have seen worn ovaled on several Briggs V-twins.
that makes sense, i guess. So, the guides i've been looking at (without the rubber O ring) should be the correct ones. As for the piston movement, you're right. I read that when it's at the top of the cylinder it will move back and forth slightly. thanks for the feed back!! I really appreciate it.

I don't normally get into engines like this but, the mower was a gift from my wife and it's in perfect shape except for the smoking.

motor:
446777-0244-E1
030425YG

it's on an Electrolux Poulan Pro Garden tractor....bought back in 2006
 

StarTech

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With that already being three years old (2003 engine per the above date code) by the time you got the mower anything could have been done to it. But the manuals showing that Intek without o-rings is what I normally see here in the shop. I don't where the o-rings came from but they not normally there.
 
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