• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

Komatsu d39-21a issue

Dyson excavating

New Member
Joined
Aug 25, 2024
Messages
1
Location
West ky
Hello I’m new to the komatsu world and have a 2008 d39-21a dozer.
great little finish dozer but sometimes when running (usually in reverse) it was kinda jump like you went to neutral or hit the brake just a split second. Does it in forward but not nearly as often. Have also noticed that mainly only does it when the ac is on?
I’m thinking it is electrical but wondering where to start? Battery’s? Altenator? Hst issue?
Any help or advice great appricate!
 

Jlyons

New Member
Joined
Aug 15, 2023
Messages
2
Location
Texas
Go to service screen and watch your hat pump epc currents. The coils could be getting hot and dropping out.
 
Top