we just bought this dozer at an auction. Before we got it home the hydraulics stopped working and the auction company replaced the hydraulic pump. We drove it in high gear about 1/2 mile to get it to our place and smoke starting coming out after using deceleration pedal. Hydraulic fluid seemed extremely hot. White smoke was coming out from hydraulic compartment and near the front of the machine. When I stopped the machine the blade had a hard time tilting. It was working just fine before. Thanks in advance.
Just a guess but it sounds like you have a hydraulic oil leak that is spraying on something hot on the engine. Fill the hydraulic tank, open all the compartment enclosure doors, and start the machine at an idle...….see if you notice any leaks. If not, start operating functions one at a time......if there is a leak you should see it quickly.
Thanks for the response. Not seeing any leaks. The smoke is coming from two different places. And it started after I used deceleration clutch. Could the deceleration pedal have something to do with the hydraulic fluid overheating? Thanks
You really need to narrow down as to what areas specifically you have smoke coming from. A machine serial number may help with someone who has Komatsu tech support.
Not familar with the machine but a couple of random questions. Is there any hydraulic temperature readout on the dash..? If there is one does it work..?
Ive got a d41P serial B20203 doing the exact same thing. Smoke will come from hydrualic pump itself if you let it get hot enough. opening the hydraulic tank will get a bunch of smoke. these machines are not equiped with temp of work circuit, just trans temps.
Might be copious amounts if that fresh auction paint they cost everything with, burning off.
Possibly on the original poster's machine but not on mine. Its done it on 2 different control valve sets about 6 months apart.
That’s strange.
sounds like there is a valve stuck does it have a 3rd valve could be engaged and going over relief can you put a gauge on the pump to see if if under load
It has to be underload because it is creating enough pressure to overheat the unload valve at just idle rpm.
My brother is a crane mechanic in Houston. I sent him my schematic and he found a pilot bypass valve that could be causing my symptoms. I cleaned that valve and it seems back to normal. It will be on a job Tuesday and he said I should go prepared to clean it several times because it only takes one small grain of contamination to cause that issue and until the oil has been throughly filtered, its likely it will happen some more. He also said it might be more common on dozer, but he said having a gear pump pushing a load sense system is not seen in his field. He wasn't to impressed by the design. He feels that its prone to failing more often than the piston pump counterparts.
I am trying to just find a place to buy an unload valve from and have not had any luck. What ever happened with your situation? did you get the machine back up and running?