1991 25 hp Evinrude help...

[Airslot]

Hey guys. *Looking for a little input on my 91' 25 Rude for the skiff. *She runs great but won't idle just right. *I'm thinking something along the lines of a bad crankcase seal because at idle she'll sneeze, but not through the carb. *The sneeze comes from under the flywheel. *The usually happens when it stalls, or casues it to stall. *Runs like a raped ape above idle. *Any ideas? *Think I'm on the right track? *Skools....?

Edited to add...she's got a fresh rebuild on the carb and fresh gas.

Airslot

[reelapeelin]

Gasket/seal good on the carb reinstall after rebuild?...

[macojoe]

well its eaither gas air or eletric??

Gas should be fine if rebuilt right, Air if you have bad gasket and did you tune and replace spulgs wires coil or the points??

[Airslot]

I guess the specific question is why is the sneeze coming from under the flywheel. When it sneezes (like a lean idle sneeze) the little puff of smoke comes from up under the flywheel. Plugs are new top plug is cleaner than the bottom plug after an hours use.

Airslot

[macojoe]

well the points are under the fly wheel, ck them out!

[Airslot]

Something is allowing combustuion gasses to escape under the flywheel. I'm just wondering if it could be anything other than the top seal around the crank. Come on skools, you the omc man...

Airslot

[reelapeelin]

Good time to try this guy out...bet he can tell ya ZACKLY what's goin' on under that flywheel ;)...let us know...

http://www.wellcraftv20.com/cgi-bin/yabb/YaBB.cgi?board=Links;action=display;num=1145285408

[Geekie1]

Hi Airslot,

Try this website:

http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi

Whenever I have a problem with my Yammie or Rude I go to this site. They have people on this site that are professional outboard techs (mostly retired) and I can say without hesitation that they know their stuff. I had an ignition problem with my 150 Yammie that would have cost me $1000+ to repair by a Yammie shop. I replaced the CDI unit myself after troubleshooting the problem (no spark) with Iboats forum help and saved me over $500!!! You need to register and then you can start asking questions. Make sure you have the make, year, model #, in your post up front. I hope this helps!!

Ed G.

[Skools Out]

there's a ring seal for each cylinder on the crank if you are getting exhaust look for a crack in the block. how is the compression on the motor?

[Airslot]

Thanks Skools. I haven't done a compression check because the thing runs great once it's above idle. Actually, runs as good as new. She stumbles at idle and will "sneeze" like it was lean, but not through the carb. The sneeze comes from under the flywheel. I guess I'll just pull it and take a look. I'm thinking that there is a seal along the lines of a "rear main" at the top of the block. I think this is where the sneeze is coming from. Just wondering if I'm headed in the right direction or if I'm nuts.

Thanks,

Airslot

[pikfish]

I have not seen your motor but let me make a general statement; On any motor and especially a small one, the idle jet is very small! This means that any gum or other contamination will clog it first. If you have left the motor sitting for any length of time, the fuel will clog the idle jet and cause it to not idle but may run at higher RMP’s OK (on the other larger jets). The fix is to drop the float bowl and unscrew the idle jet and either clean it or replace it.

[Skools Out]

take off the flywheel and show us pics. there is a seal in the top and bottom main bearing holder.