Export thread

Scag wildcat fuse heating

#1

M

Mstrate

I have a scag wildcat 11 years old, been garage kept, worked great until 2 weeks ago when it started blowing the lower"yellow wired" fuse. Tracing wiring and Looking at connections...all good. Clean and no corrosion. Replaced ignition switch, voltage regulator and stator. The two yellow wires are heating up rapidly with throttle fwd and blades disengaged after about 10 seconds. Voltage to battery is 13.6. Plus yellow singe wire on ignition switch gets extremely hot as well. Other than replace fuse holder I'm running out of options. Also, If I remove connector on voltage regulator the wiring does NOT heat up but battery not charging. Open for suggestions.
Engine number CV7 40S. S/N 3502731241.


#2

BlazNT

BlazNT

What does not work when the fuse blows?


#3

M

Mstrate

Engine will stop once fuse blows. Mower will turn over and start for about a second and immediately die. Replace fuse and it will start and run for a short time until it blows again. However the wiring going to fuse is too hot to touch and so is ignition switch


#4

BlazNT

BlazNT

To me, that sounds like a bad connection in the key start switch. When it cools down check the fuse wire both directions for it touching metal. If you do not find short to metal test the key switch.


#5

M

Mstrate

Changed fuse holder and that seem to fix it. Still gets hot but does not blow fuse


#6

M

Mstrate

Here's the latest. New stator, voltage regulator, fuse holder, starter switch and battery. Mowed for two hours and PTO switch and connector melted. Guess I will replace clutch, wire harness and PTO switch unless anyone has other suggestions. Thanks in advance


#7

jekjr

jekjr

I have a Tiger Cat that will blow about 2 fuses a day. Always the bottom one. It will run but if you turn it off it won't start back unless you jump it off. If you run it long enough without catching it then the PTO clutch will not work....... Until a new fuse is installed.....


#8

M

Mstrate

Mine was similar but now connector is melted for PTO. Hate to replace clutch but if I put new harness on it and don't replace clutch then I could be doing another harness. I put new fuse holders and that fixed the original problem


#9

jekjr

jekjr

We replaced the fuse holders on my Tiger Cat Thursday and ran it a long time Friday and did not blow any fuses. The Jury is still out if that is the problem though.


#10

EngineMan

EngineMan

Try disconnecting the clutch wire(s) and then see if fuse gets hot.


#11

NorthBama

NorthBama

check the ohn resistance on the clutch coil with vom meter


#12

S

Scottyboy

Fuses melted in the holder with out blowing. Changed the fuse holders. No problems with fuses getting hot.


#13

M

motoman

People here have briefly touched on the expected running current of an engaged clutch, but not a lot of detail. Perhaps a tricky setup,but worthwhile to set up the DVM for current and insert it in series with the clutch while running. This may not be so easy as typical DVMs only tolerate about 10 Amps before the internal DVM fuse blows (it can be replaced). I have seen DVMs with 20 amp capacity, but it was on a lower end H Frt unit which was made me doubtful. Before such a test the mfgr's spec should be available or the pro's here should chime in. I believe the brief conversation before was around 15 amps. I ran a similar test on an Audi fuel pump and it was effective. Audi had published the current spec. A resistance check is another approach as noted above if expected value is available.

Perhaps there a factory notice on such a pattern problem? :2cents:


#14

H

Honda Tech

motoman said:
People here have briefly touched on the expected running current of an engaged clutch, but not a lot of detail. Perhaps a tricky setup,but worthwhile to set up the DVM for current and insert it in series with the clutch while running. This may not be so easy as typical DVMs only tolerate about 10 Amps before the internal DVM fuse blows (it can be replaced). I have seen DVMs with 20 amp capacity, but it was on a lower end H Frt unit which was made me doubtful. Before such a test the mfgr's spec should be available or the pro's here should chime in. I believe the brief conversation before was around 15 amps. I ran a similar test on an Audi fuel pump and it was effective. Audi had published the current spec. A resistance check is another approach as noted above if expected value is available.

Perhaps there a factory notice on such a pattern problem? :2cents:
Click to expand...

First, this unit should have an Ogura adjustable clutch. With feeler gauge, you want .015" airgap at all three inspection ports. Excessive airgap will create excessive resistance and 'melt' fuses. Resistance @ 70 degrees should be 2.8~3.2 Ohms. If you can perform an Amp Draw test, it should be 5.67 Amps.
Don't overlook loose or poor Ground connections!!!


Footer Links 1

Top