Register free!

The Green Industry's Resource Center


Reply
 
Thread Tools   Display Modes
  #1  
Old 06-22-2012, 12:21 AM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
Scag Rough Idle

I just bought a 48" Scag hydro W/B. It has Velocity deck which makes it at least an '06 if my info is correct. It ran great first few times I ran it, but I started it the other day and the idle has turned rough. Almost a repeating "surge", not a steady idle. When I throttle up the pattern happens faster. I changed plugs, fuel filter and hose.... No change. I'm seeing some black smoke puffing out on start up also. Plugs were dry, but obviously old. Could you guys help me out?
Reply With Quote
  #2  
Old 06-22-2012, 08:39 PM
weldondl weldondl is offline
LawnSite Member
 
Join Date: Jun 2007
Location: Granbury,TX 76087
Posts: 33
more info please

When posting a thread about the problems you are having with your equipment:

Please give a full and accurate description of the problem you are having and what you have already done to correct the problem. It will also benefit you to post all model and specification numbers off your equipment.
Machine problem - machine numbers.
Engine problem - engine numbers.
This will aid in letting everyone know exactly what equipment you have and to give you a quicker and more accurate response to the problem at hand. We do have some Service Technicians here on Lawnsite and some have Technical Support at their fingertips but need model numbers to access proper information.
Thanks For Reading.
Good Luck
Reply With Quote
  #3  
Old 06-22-2012, 09:00 PM
Patriot Services's Avatar
Patriot Services Patriot Services is online now
LawnSite Fanatic
 
Join Date: Jul 2006
Location: Tampa FL
Posts: 8,678
Not knowing how long it sat around, I would bet a thorough carb cleaning will fix your problems. Check the mounting gaskets and intake block too for possible vacuum leak. Black puff on startup is normal especially if you have the choke on.
Reply With Quote
  #4  
Old 06-22-2012, 10:39 PM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
Copy that! Thanks for the input. I'm just getting started with a commercial mower and the deal turned out to be a little shady. I just don't want to get it out mowing and make a potentially small problem into a big (expensive) one. I appreciate the feedback very much. I will provide serials next time.
Reply With Quote
  #5  
Old 06-22-2012, 10:46 PM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
I don't have serials for the engine unfortunately. Mower is SWZ - 48V17KAI. Serial is C1000... . I bought the mower from a private seller, and it showed signs of having sat... Hydraulic filter had flaked paint and rust, tires slightly dry rotted, etc. What confuses me is that it started, idled and ran nice and smooth. I ran it at idle twice on and off for thirty minutes during the week to adjust the tracking, neutral, etc. and the following week the rough idling started.
Reply With Quote
  #6  
Old 06-22-2012, 10:48 PM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
Could you go into a little more detail on what you mean by "carb cleaning", Patriot Services?
Reply With Quote
  #7  
Old 06-23-2012, 02:35 PM
Patriot Services's Avatar
Patriot Services Patriot Services is online now
LawnSite Fanatic
 
Join Date: Jul 2006
Location: Tampa FL
Posts: 8,678
Quote:
Originally Posted by GreenWillowLandscapes View Post
Could you go into a little more detail on what you mean by "carb cleaning", Patriot Services?
Sure. I have the 19hp version of that engine on a Cub. Just unbolt the carb and disassemble it. Chances are the float bowl will be full of a sandy grit. Use spray carb cleaner to flush out every passage. Replace the float, needle and seat. Reassemble and reinstall. Should run like new. Carbs really dont like to sit with todays fuels for extended periods of time.
Reply With Quote
  #8  
Old 06-23-2012, 10:51 PM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
Great! That helps a lot. Thank you very much!
Reply With Quote
  #9  
Old 06-24-2012, 12:24 AM
The Lawn Ranger CT.'s Avatar
The Lawn Ranger CT. The Lawn Ranger CT. is offline
LawnSite Member
 
Join Date: May 2010
Location: westhaven Ct
Posts: 194
I agree with Patriot on checking the "mounting gaskets and intake block too for possible vacuum leak".~ While the engine is running on idle and surging spray some carb cleaner around the intakes where they enter the head , if the idle increases then its the intake mounting gasket... I had a few of these go and cause the same issue~
Reply With Quote
  #10  
Old 06-24-2012, 12:59 AM
Green_Will Green_Will is offline
LawnSite Member
 
Join Date: Feb 2012
Location: Pennsylvania
Posts: 63
Copy that. Thanks Lawn Ranger.
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

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump





Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Moose River Media
All times are GMT -4. The time now is 01:59 AM.

Page generated in 0.08203 seconds with 7 queries