DieselTalk

DieselEngineTrader's FREE Diesel Engine Forums

new topic search Categories login View Kubota Engines

CATEGORY LISTINGS > KUBOTA > Kubota Loss of Power [ REFRESH ]
Thread Title:

Kubota Loss of Power


Created On Sunday May 09, 2010 21:03 Diesel Talk
Diesel Talk Forum

petersonnate
Diesel Talk Forum
Posts: 1
Joined: May 2010

Note Sunday May 09, 2010 21:03 View thread in raw text format
Diesel Talk
I have Bobcat excavator 337 with a 4 cylinder Kubota Diesel. The problem has been going on for a year or more when it slowly started loosing power. Here are the items I’ve completed.

1) Put on a new cam run lift pump mounted to engine
2) Added an electric lift pump in place of the primer ball (pull through pump so I can leave it off if I want) just to see if the cam itself was worn out operating the cam lift pump (process of elimination).
3) Took injection pump off, with all injectors, had them rebuilt.
4) Installed new rings (over 400psi in all cylinders now +/- 20psi)
5) At this point brought is the the Bobcat dealer who said “you need a new pump”. OK….$5600 later I get it back. Still looses power.
6) YES…..replaced all the filters


Took it back to the dealer who ran every hydraulic test on it that they could, took the pump back apart again, (found a faulty pump controller), put it all back together and they (and I am too) are confident the pump side of the system is right.


So right now this is how it acts. I can start it up and runs great. I have about 4 to 8 minutes of full power at which time it starts to bog down, slowly at first, then the engine starts a light knock (more like a tap…growing to a knock), if I stop digging/driving the RPM immediately goes right back up. Then if I touch one of the hydraulics is pulls back down just as fast. (in this state if I were to push the drive levers full forward it would kill the engine in about 2 ft of travel). I can limp around at this state (very very slow crawl, basically the engine cannot take any torque). The machine does have a temp gage which does show movement but not hot, the oil pressure alarm is not functional, and when its running I can grab the hydraulic return line before it goes into the hydraulic radiator with my bare hand so it is not that hot. I took the thermostat out the other day (just in case it was stuck shut…no difference). At this point I’m thinking it might be overheating (It would not surprise me if the gage is not functioning) but the radiator does not overflow when running (YES..its full), or maybe the oil pump is out (but if it was I think I would have had something real bad happen a long time ago)…… These are my current guesses…but I’ve been guessing for close to a year and $8000!!.... I’m hoping someone has a few thoughts that I might be overlooking. HELP PLEASE!!


-------------------------
Horecky
Diesel Talk Forum
Reply Diesel Talk Forum Quote Diesel Talk Top Diesel Talk Forum Bottom Diesel Talk
Diesel Talk Forum
CATEGORY LISTINGS > KUBOTA [ REFRESH ]
Adelman's Truck Parts Corp.
Adelman's Truck Parts Corp.
Luoyang Diron Parts Trading Co.,Ltd
Big Bear Engine Company
Diesel Sales
Young & Sons Inc.
Advertize on Diesel Engine Trader

Customer Testimonials

Newsletter

Subscribe to our mailing list to get all the latest DET news.as well as daily or weekly notifications of new engines, gensets and spare parts listings.

'We bought a new John Deere engine via DieselEngineTrader.com for a great price and were able to sell it locally for $1000 less than our competition. We really appreciate the website - it's great!'

Ben Kauffman, Quaker Machine, PA, USA

'Sold one of my Detroit engines via DieselEngineTtrader.com and it was to a local guy!'

Wil Tiefenbacher, United Lock-Block , British Columbia, Canada

'Been using DieselEngineTrader.com since 2010, it's much better value than eBay and works pretty good for us!'

Lius, R & L Diesel Service Inc, Stockton, USA