L45 front 3rd Function Fuse Blowing Intermittently - HELP!

akgsaab

New member

Equipment
Kubota L45
Aug 10, 2020
8
2
3
Nevada City, CA
Hi all. I have a 2013 L45 with the factory third function valves on the FEL. The fuse, which enables the press button switch, blows intermittently when the switch is enabled. I have replaced the switch and wiring but it continues to blow without any discernible specific thing that I do that causes it. I am not even sure that it blows when the valve control is in use.

Has anyone experienced this or any ideas on where to start tracing? It is very frustrating, especially when using the 3rd function valve for snow plow angling.
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,853
113
Sandpoint, ID
Sounds like you have a coil that is shorting out.

Replace the fuse with a resettable circuit breaker of the same size, will make it easier to find the part that is failing.
 
  • Like
Reactions: 1 users

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,853
113
Sandpoint, ID
Great idea. How would I be able to test the coil? Any ideas for me?
Measure the coils with a multimeter on beeper or ohms, one lead to either coil wire and one lead to metal on the valve or the tractor.
You could also measure between the two terminals on the coil, and compare the two coils.
They should be between 10 and 100 ohms.
Look at the coil body for cracks or swollen areas.
 
  • Like
Reactions: 1 user

akgsaab

New member

Equipment
Kubota L45
Aug 10, 2020
8
2
3
Nevada City, CA
Measure the coils with a multimeter on beeper or ohms, one lead to either coil wire and one lead to metal on the valve or the tractor.
You could also measure between the two terminals on the coil, and compare the two coils.
They should be between 10 and 100 ohms.
Look at the coil body for cracks or swollen areas.
Thank you. I will investigate further tomorrow. For now both are reading 4.8ohms across the terminal connections.
Any thoughts on that reading?
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,853
113
Sandpoint, ID
Thank you. I will investigate further tomorrow. For now both are reading 4.8ohms across the terminal connections.
Any thoughts on that reading?
That sounds good, but they could still short to ground.
 
  • Like
Reactions: 1 user

555

Member

Equipment
B2601
Sep 15, 2022
45
87
18
Ontario
Hi I just put a Kubota third function valve on my B2601, it went good. But when I tested the switch I heard a klick from the 3rd function valve. Upon investigation, Kubota had put a 5 amp fuse in for the accessory wire which is not much good for anything. According to the service manual it can take up to 35amp fuse. After putting a heavier fuse in it works fine. Food for thought.
 

fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
6,312
4,001
113
Eastham, Ma
Hi I just put a Kubota third function valve on my B2601, it went good. But when I tested the switch I heard a klick from the 3rd function valve. Upon investigation, Kubota had put a 5 amp fuse in for the accessory wire which is not much good for anything. According to the service manual it can take up to 35amp fuse. After putting a heavier fuse in it works fine. Food for thought.
Kubota obviously had a LARGE supply of 5A fuses,.... and no other use for them? ;)
 

mikester

Well-known member

Equipment
M59 TLB
Oct 21, 2017
3,125
1,609
113
Canada
www.divergentstuff.ca
Hi I just put a Kubota third function valve on my B2601, it went good. But when I tested the switch I heard a klick from the 3rd function valve. Upon investigation, Kubota had put a 5 amp fuse in for the accessory wire which is not much good for anything. According to the service manual it can take up to 35amp fuse. After putting a heavier fuse in it works fine. Food for thought.
A 35A fuse to replace a 5A is a great way to locate your bad connections...just follow the smell and look for burnt wires. You might even hear some buzzing initially.
 
  • Haha
Reactions: 1 user

555

Member

Equipment
B2601
Sep 15, 2022
45
87
18
Ontario
I should have clarified that I put a 10 amp fuse in place of the 5 amp to start with. I will see if it is heavy enough once I get my homemade grapple hooked up. THKS
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
9,672
3,921
113
Greensville,Ontario,Canada
both coils read 4.8 ohms. nominal battery voltage is 13.2
current is v/r, 13.2/4.8 = 2.75 amps, so round up to 3 amps
This means the 5 amp fuse is a 'good' choice,7.5 would be the max though.
Coils are 'inductive' loads and can draw 10x their holding current, but only for a brief time. All fuses can withstand this 'inrush' current.
While the manual says that fuse position can have a 35A fuse, you would need 8 gauge wire to power the 'device'. 8 ga wire is 'fat', like on a car alternator. I suspect the 3rd function wires might be 18 gauge, like the E-pto on riding mowers.

Somewhere between the switch and the coil there is a 'grounding' issue though I'd have to see the wiring diagram and some pictures to better diagnose. Though rare it could be the coil where part of the winding is connecting to the plunger,so perhaps remove the coil and inspect very.very carefully.
 
  • Like
Reactions: 1 user

TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
6,668
3,214
113
Myersville, MD
windyridgefarm.us
I should have clarified that I put a 10 amp fuse in place of the 5 amp to start with. I will see if it is heavy enough once I get my homemade grapple hooked up. THKS
Disconnect the coils and operate the switch. If there is a short to ground in the wiring harness the fuse will still blow. If it dors not bloe the probkem is in the valve.

Dan
 

akgsaab

New member

Equipment
Kubota L45
Aug 10, 2020
8
2
3
Nevada City, CA
Disconnect the coils and operate the switch. If there is a short to ground in the wiring harness the fuse will still blow. If it dors not bloe the probkem is in the valve.

Dan
I may have found my culprit thanks to all the advice here. I started pulling on parts of the harness and exposed an area that doesn’t have a protective sheathing and runs near a relatively sharp sheet metal a the bottom of the loader stick housing.

When it’s light I will evaluate further. The harness is $110 or I may be able to just repair and heat shrink. 🤞

More to follow!
 

Attachments

Last edited:
  • Like
Reactions: 1 user

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
9,672
3,921
113
Greensville,Ontario,Canada
hmm.. wht/red wire randomly hits sharp orange steel = POOF !
sounds like you FOUND it !!
while you're 'in the neighbourhood', plug the ends of that connector with yellow wire, to minimize corrosion and THAT failing in the future....