http://www.snowmobileforum.com
Go Back   Snowmobile Forum: Your #1 Snowmobile Forum > Specific Snowmobile Forums > Vintage Snowmobiles

Please Visit our Site Sponsors


» Sponsors
» Our Partners
» Sponsors
Reply
 
LinkBack Thread Tools Display Modes
Old 03-27-2008, 12:29 PM   #1 (permalink)
P Bradley
Registered User
 
Join Date: Feb 2008
Posts: 15
Engine revving up and down during idle

First of all - thanks to everyone that has helped me get my Yamaha ET250 almost running! Here is the latest twist....After running pretty well over the past two weeks (with full tank), I started it so my son could ride around the yard. Although it would start, I could not get it to move - kept bogging down with throttle. Not only that, but while "idling", the damn thing kept revving up and then back down again. It will do this for 5 minutes and then stall. I sprayed the clutch-side seal with ether, but it didn't alter the revving pattern. Eventually I got it going after a lot of feathering of the throttle, and then it ran pretty well, idled OK too. No change in idle speed with ether sprayed at seal. Why is it doing this?
P Bradley is offline   Reply With Quote
Sponsored Links
Advertisement
 

Old 03-27-2008, 03:06 PM   #2 (permalink)
RJ Gleason
Moderator
 
RJ Gleason's Avatar
 
Join Date: Feb 2005
Location: Groton NY
Posts: 10,195
Possible moisture in gas........
Put a couple of oz. of fuel drier in it with the next tankful.
__________________
Old Cat Rider


w/ Comet 108 Pro-4 clutch


80 PANTERA 500 F/C w/ Comet 102 clutch

'90 Wildcat Project in progress.

Trail Boss; Dryden to Summerhill trail.
http://www.dcdrifters.net/

Senior Deacon; F&AM Lodge# 472

RJ Gleason is offline   Reply With Quote
Old 03-27-2008, 07:32 PM   #3 (permalink)
smallengineguy
I am Spartacus
 
smallengineguy's Avatar
 
Join Date: Feb 2004
Location: Milton Mills, NH
Posts: 15,393
Drain the carb bowl, probably water in there.
__________________
1992 Ski Doo Mach 1 (SC-10/2 suspended) March '07 SF.com Sled of the Month!
1993 Ski Doo Mach Z 780 triple
2001 Ski Doo Mini Z



Evergreen Valley Snowmobile Club Webmaster

If I'm not home, CHECK THE TRAILS!
smallengineguy is offline   Reply With Quote
Reply



Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Powered by vBadvanced CMPS v3.0 RC2
Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.0.0 RC8
Copyright SnowmobileForum.com