2008 DK 55 Injection pump problems at 500 hours

[walkerj]

I'm new to the forum world so forgive me if I mess up.

A few weeks back my tractor started to crank longer and longer to get started until it wouldn't start. I found that the lift pump had gone bad. After replacing said pump and bleeding the system the tractor started right up. Even with the lift pump corrected, it still had to crank much longer than usual (I have been looking for air leaking into the system with no luck) to start until just this week it would not start at all. Lift pump is operational and I have fuel to the injection pump. I haven't tried to bleed injector 1 but injector 2 has good fuel, injector 3 has a little less and I can not get any fuel out of inject 4 no matter how long I crank. I'm assuming it's an injector pump problem but certainly don't feel comfortable diving in on my own. Any thoughts? Could the IP just have an air lock?

 

[carpenter383]

I have read about problems with many of kioti's injection pumps, but I thought the 2008 and newer models were supposed to be "fixed" If I remember right it was something about a spring loaded plunger that would snap back too fast and break at the no 4 fuel outlet area (inside the pump). The IP has to be torn apart to be fixed, not sure if it's a diy job or not.

 

[DK35vince]

I have read about problems with many of kioti's injection pumps, but I thought the 2008 and newer models were supposed to be "fixed" If I remember right it was something about a spring loaded plunger that would snap back too fast and break at the no 4 fuel outlet area (inside the pump).

If I remember right, it was the 2006-2008 models that were having the injector pump issues.

 

[Coyote machine]

It was a run on at full throttle condition that was caused by the rack jamming and not allowing for shut down of the tractor. IPs can fail in either direction, causing no start or no stop conditions. Don't blame the pump until you have ruled out other possible causes. Fixing is NOT possible- NO parts are available for rebuilding or re-manufacture. Kioti, or possibly Bobcat are only viable sources.
Welcome to TBN.:confused3:
Good luck. Post back results.

 

[BethelHntr]

:welcome: to TBN Lots of good info here, Come on in and stay a while.

 

[ritcheyvs]

This is a link to the data I compiled on IP failures based on posts on TBN:

http://kittrellcommunitywatch.dyndns.org/Kioti_IP_Data

I'd check the glow system just to be sure, but zero flow from one injector while you get flow from others points strongly to the IP.

 

[BethelHntr]

This is a link to the data I compiled on IP failures based on posts on TBN:

http://kittrellcommunitywatch.dyndns.org/Kioti_IP_Data

I'd check the glow system just to be sure, but zero flow from one injector while you get flow from others points strongly to the IP.

Excellent compilation ritcheyvs.

 

[walkerj]

I was told by my injection service that they had a Kioti IP 3 cylinder on their desk. Also the dealer said they could send it off to be re built in Indiana. I keep hearing that after the 2008 models the IP's are fixed. If so I'm hoping they can upgrade it so it won't leave me stranded again.

 

[carpenter383]

If I remember right, it was the 2006-2008 models that were having the injector pump issues.

That sounds right, I have a 2008, hopefully it has the "fixed" IP

 

[ritcheyvs]

I was told by my injection service that they had a Kioti IP 3 cylinder on their desk. Also the dealer said they could send it off to be re built in Indiana. I keep hearing that after the 2008 models the IP's are fixed. If so I'm hoping they can upgrade it so it won't leave me stranded again.

These things are definitely rebuildable if you can get the parts and have a test stand to recalibrate the IP. The issue seems to be some contractual crap between Bosch (now Zexel) and Doowan who licensed the design from Zexel. The reported failure modes where were broken teeth on the rack and/or gears and also broken springs in the delivery valves (one case in a DK55). Speculation is that the new style shutoff solenoid (beginning in 06) delivered higher loads to the gear teeth, sometimes breaking them (see the top link in the spreadsheet for teardown photos).

Some Diesel shops will fix these IPs while other Bosch/Zexel certified shops will not touch a Doowan IP. Most folks here ended up buying a new IP from Kioti or from Bobcat (who sold white Kioti tractors for a time). There were (maybe are) dealers on this board who may make you a deal below list. It's a shame because a new IP lists for $800-1600 (roughly) depending on model and they can be easily repaired for a few hundred bucks (given parts, tech data, and contractual approval). If you have a willing Diesel shop, I'd definitely try repairing your IP before sending the $$$ to Kioti. Personally, I think it's a disgrace that Kioti doesn't stand behind these. They could repair them for little money and buy a LOT of good will.

If you isolate the exact problem with your IP, it's possible other TBN posters might have the needed part from their failed IP.

The basic mechanical IP concept is very similar to the old Mercedes Diesels, which were famous for going well over 500K miles on the original engine and IP. At one time, used Mercedes IPs were very cheap on Ebay because there was no market --they (almost) never failed. The Kioti IP is just the top half of the Mercedes/Bosch design because the cam part is internal to the Kioti engine block (vs being part of a separate IP unit in the Mercedes design). This is a lot of rambling but my point is that the basic design was extremely robust to the point failure was almost non-existent when quality metallurgy and machining processes were used. However, Mercedes did use a vacuum motor to shut off the engine where Kioti uses a stop solenoid so perhaps that created excessive shock load on the gears. The broken delivery valve springs (which could also be your problem) have got to be defective original parts.