View Full Version : 48" scag tiger cub 19hp kaw problems

05-07-2010, 05:50 PM
After a long day of mowing the mower was allowed to rest a while. My wife started it back up to mow a little more and every time you try to move it loses power and when you engage the blades it does the same. If you try to move it while the blades are engaged it'll almost cut off. This has been over a week now and I still haven't been able to figure it out. It runs normally unless you try to move or engage the blades.

05-07-2010, 08:01 PM
Sounds like you have a bad operator presence switch (seat safety switch). It can be tested with a multimeter set on ohm's scale to see if it's opening and closing when activated.

You could also unplug it and add a jumper wire for test purposes ONLY to see if that's the problem.

The Lawn Ranger CT.
05-07-2010, 09:33 PM
That a V twin~!~? try checking the coils and plugs to see if your firing on both....I found out once (when I had a bad coil) that it sounded and ran great , firing on one cyl., until I engaged the blades or put a load on it., and it would almost cut right out on me .

05-08-2010, 12:19 PM
Thank you for your responses. I'm going to try both suggestions before I take it to the shop.

05-08-2010, 01:11 PM
I just found that it's only running on one cylinder. It's only getting a weak spark from the coil wire to the spark plug and the spark plug looks fine. I reckon that I better take it to the shop since it's under warranty. Thanks again Lawn Ranger.

The Lawn Ranger CT.
05-08-2010, 10:09 PM
No problem and glad to help.... hope the dealer can make it a quick fix for you, coils are easy to replace and set if that is the problem, and should still be covered under the warranty.
Now if I could only get mine fixed and running right~!

05-23-2011, 12:19 PM
I have a 48" Scag Turf Tiger the 25 hp V-twin engine. It sounds to be the exact same problem you were having, but mine is not under warranty. It has been at the mechanics for over 3 weeks and he is totally stumped.

First of all, we know the head and rocker arm were mutilated, so we replaced those. It still had the original problem, so he moved to other things. He has replaced the coil, cleaned out the carburator, new air filter & oil change, new spark plugs, checked fuses. He also says it looks to be getting intermittent fire on the left side of the engine, where the head was replaced (left side, if you're looking at the mower from the rear).

Any other suggestions? Do you recall what the problem was with your mower? I'm thinking it could even be a problem with the PTO because it does it when the blades are engaged...but then again, I also doubt that because it also happens if you put a load on it (i.e. giving it full throttle speed).

ANY IDEAS?? Thanks in advance!

07-31-2011, 11:39 PM
My problem ended up being bad gas fouling everything up, according to my shop. They fixed it and covered it though because they had agreed with me on the phone that the coil was probably the culprit. Now I use Sta-Bil Marine Formula as they suggested.

08-02-2011, 05:45 PM
I'm assuming that he replaced the coil on the side with intermittent spark. With the head work that was done, has he measured the compression afterwards? Poor compression can also cause one cylinder to misfire. With it being on one cylinder only, that would seem to rule out the ignitor, if your module has one. Does it have two different pulser coils on the flywheel? Maybe the one for cylinder one is bad. Has he ohmed out those?

08-02-2011, 05:55 PM
We finally got it fixed and figured out what was going on. He had replaced the coil, as well as traced all components, checked the gas, gas lines, carburator, EVERYTHING. It had GREAT compression on both sides of the engine. Finally, after being on the phone with Scag for the 3rd time, they told him that possibly, since he replaced the #1 coil, that possibly it no longer matched up with the older coil. So he replaced the "good" coil #2 and, VOILA! It was fixed!

Thanks for all your help!

08-02-2011, 06:08 PM
So what you are saying is that it was firing on cylinder one and not two after doing all that work to one? That's wierd.