15 amp fuse blows

rich0587

Forum Newbie
Joined
Aug 22, 2025
Threads
1
Messages
3
Hello, I'm new to this forum. I have a Hustler Raptor SD #934778 with a Koehler 26hp engine. The 15 amp fuse started blowing yesterday. It will restart and now for a few minutes then blow again. Went thru about 5 fuses this way. No apparent shorts in wiring harness. Can not find a wiring diagram that even shows the orange fuse holder wire or where it runs and attaches. Any help?
 

clubairth

Well-Known Member
Joined
Apr 6, 2015
Threads
4
Messages
173
How did you determine there are no shorts?
Use a meter? You will need to follow the wires and using your meter to figure out what is bad.
Sometimes I remove a connection or two to eliminate sections of the wiring harness.
.
.
.
 

Auto Doc's

Lawn Addict
Top Poster Of Month
Joined
Sep 7, 2024
Threads
15
Messages
1,207
What does that 15A fuse power? If it for the crank circuit, the starter solenoid is likely breaking down the pull in windings.
 

Auto Doc's

Lawn Addict
Top Poster Of Month
Joined
Sep 7, 2024
Threads
15
Messages
1,207
I have not dealt with any riders or zero turn mowers with an electric PTO that have a 15A main fuse. All the ones I have dealt with have a 20A fuse. Could the diagram be lying?

I also have to question the quality of the fuse(s) being used. Cheap online bulk fuses are garbage and have lots of problems.
 

sgkent

Lawn Addict
Joined
Sep 27, 2017
Threads
35
Messages
1,894
James Condon just did a video this week where the 15 amp fuse on a standby generator engine was blowing randomly and it was a combination of the starter solenoid pulling too much current due less than a perfect battery voltage, combined with a problem connector in the charging circuit, which was keeping the battery from charging to full capacity. The problem is that when the solenoid pulls in, which closes the buss bar inside it so the starter draws directly from the battery, if that connection inside the solenoid has any resistance in it, or if it does not pull all the way in due to a slightly less than optimum battery voltage, the fuse ends up carrying the extra current.
 

StarTech

Lawn Royalty
Joined
Feb 19, 2020
Threads
114
Messages
12,300
Ever thought about a carburetor fuel solenoid starting to short out? I had several over the years to develop shorts. Btw the electric PTO clutch should never be pulling more than 7 amps which is why some OEMs actually fused them at 7.5 amps. Also solenoids and relays coils can partially short and draw more. Note this mower does use both a fuel solenoid and a kill relay that are powered anytime the keyswitch is on. Even the hour meter can partially short.

Only lower overall resistance in the circuit causes higher current not higher resistance; higher resistance equals lower current. Study Ohms law. But some have never believe in laws.
 

Forest#2

Well-Known Member
Joined
Apr 17, 2022
Threads
0
Messages
579
might think about getting some fuse holders and fuse each individual circuit,
for example place a 10 amp fuse in the PTO clutch circuit, a 5 amp fuse in the carb solenoid circuit and a 15- 20 amp fuse in the existing fuse holder.
At first just unplug the connector at the electric clutch and test.
The lower amp fuse when in the circuit that is overloaded should open BEFORE the 15-20 amp fuse blows.
Also you can find circuit breakers to replace the fuses which saves wasting fuses until you find the overloaded circuit.

Do you have any kind of electrical tester?
 

rich0587

Forum Newbie
Joined
Aug 22, 2025
Threads
1
Messages
3
Hello, I'm new to this forum. I have a Hustler Raptor SD #934778 with a Koehler 26hp engine. The 15 amp fuse started blowing yesterday. It will restart and now for a few minutes then blow again. Went thru about 5 fuses this way. No apparent shorts in wiring harness. Can not find a wiring diagram that even shows the orange fuse holder wire or where it runs and attaches. Any help?
Update time, I was looking thru the circuit again. Noticed that there was a buildup of dirt/grass on the connector to the key switch that looked like it was crossing multiple terminals. Took connector off switch and blew all off with air compressor and reattached. Mower now starts and seems to be fixed. Seems that the dirt was causing a short that caused the 15 amp fuse to blow. Thanks all!
 
Top