i did a top end rebuid on my rancher. new piston, new rings, new sleve, cleaned valves and new valve seal and new gaskets. it doesnt smoke until i rev it up or us it for a while. when i turn it off, it it still has smoke escaping out the pipe. the pip is a glass pipe with a welded snorkel like 3 ft tall. it was coated in black powder on the inside. never cared to clean it. could that be it?? i plan on selling it soon but need to get the smoking to stop. please help

 

Some times if the engine smoked excessive the muffler can store oily deposits inside of it... try running engine for a little bit sometimes 30 to 45 mins. to get heated up enough to burn out....Good Luck...

 

Also, has the engine been broken in since the rebuild? A touch of smoke isn't unusual until the rings have seated.

You could probably tell by smell if the smoke is from the coating cooking on the muffler, or if it is oil.

 

When I fist put it together it didn't smoke. Iv put around 25 miles on it

 

Depends on how hard the 25 miles was put on... I always do in stages 1st idle and rev up some for bout 10 mins, then let cool, ride up to half throttle bout 15 mins., let cool for 10 mins or so, crank and run again bout 20 mins. and let cool. then ready to go riding. This works great for me.IMO.Sometimes engines gets run to hard to quick and ring gets soft and oil bypass them and smokes IMO.

 

This pipe/exhaust, how long has it been on there? If it is new it could be baking stuff off.

It generally takes around 10 hours to break one of these in.

Also, what was the reason for the first rebuild?

 

I don't exactly know how long it's been on the bike. I got it used. It was a mud racing bike. I took the old engine out ( it was ragged) I got an older one from a guy who rolled his bike off a cliff. It could have done ok how it was but the piston had some wear on the sides and the rings were seized in it. The sleeve was also worn so I decided to start new.

 

That's kind of new advice there. Iv always been able to start up any atv, rev it enough to get it to idle well then take off. I'll deffinaintly try it though.

 

I was wondering if the engine could have been dunked in mud and got it inside the crankcase.

I've seen a lot of folks put in new piston/rings only to have muck still in the nooks and crannies of the engine flow in the oil to ruin it again.

A slightly bent rod can also take out a new piston/rings.

Are you experienced in rebuilding engines? Any chance a ring could have been put in upside down, piston/cylinder clearance wrong, or anything like that?

 

This is actually my first project bike. I inspected the rods before I put them in. The engine from what I was told was never sunk. The piston clearance or rings could be the problem though. I installed them how the clymer repair book said to. One real quick question, how would I clean the exhaust. I don't think there is anything left in the glass pack. I would rather do that before pulling the top end off.... Again