I have a Husqvarna 1848 lawn tractor. It has 23 hours on it and is very well maintained. It has a 18hp Twin, air cooled, OHV Kawasaki engine. I am having a problem with the idle, it goes up and down when the PTO is off, when the PTO is on it idles and mows with no problem. It will never stall just irratic up and down, its worse when you lower the throttle, it sounds like it will stall then catches itself and goes back up, then repeats up then down. Choke seems to working properly. I put new plugs, fuel filter, air filter in it, carb is very clean, fuel is fresh and clean, new oil and filter at beginning of season. Any ideas why this could be happening?? Need valve tuning??

Thanks for your help

I'm guessing it didn't do this when you purchased it? How cold is it there, did it just get colder? Usually epa carbs (which can't be tuned) will make these engines (any really with a epa carb on) surge in the colder weather.

It never did this since I purchased it, even in colder temps. I live in Charlotte, NC, It was 85 the other day and the idle was up and down. The manual does say it is a non adjustable carb. Any other thoughts? Thanks for the help

About the other only thing might be some trash in the carb (looking at it tells nothing) But it could be a clogged passage... before you do anything (which may void the warranty) see if the warranty will cover it.

I am out of warranty, I looked at the carb and it looks good. I pulled it off and checked the float, gasket seal to motor, internals... everything is very clean. I think the govenor might need adjustment... can these come out of adjustment?

I'm not familiar with kawi's governors... but yes they can...

Just looking at the carb tells you nothing really.. wouldn't hurt to take it off and blow every and all holes out with carb cleaner a few good times... compressed air too if you have it.

When I looked at the carb I cleaned it using B&S carb cleaner and I blew it clean with my compressor... can you refer me to anyone who knows Kawasaki engines?

I don't know about the policy on linking to other websites...
But these guys might be able to help you.
http://www.opeonthenet.com/phpBB2/index.php

Thanks for all your help, I appreciate it :o