RTV900W6 Injection pump stuck

K

knobe

New member
Hi all... Maybe someone with experience can help me out. My RTV900 won't start. Problem has been diagnosed by a dealer but cost to repair was $2500. Evidently, the injector pump's fuel control rack is stuck and the fuel shut off solenoid lever is not moving properly. They also stated that they couldn't remove the pump from the block without the possibility of damage to the engine block or pump. So, I am now thinking of tinkering with it.
What would make the pump not be able to be taken off? Maybe if I was able to remove it, is it possible to free up the rack? Would retiming be necessary if the same pump and shims are reinstalled? How can the solenoid lever movement be diagnosed? Any information would be appreciated. Engine is a D902 and the pump is a part number 16006-51010 .
 
I would confirm that the primary pump is picking up fuel and delivering it to the injection pump before i took anything apart. I think there is a fuel rack return spring that can malfunction also"i am not sure though"
 
aurthuritis has given some excellent advice. I fought a non-start issue on the diesel generator on my boat last summer for longer than I care to admit. Finally hooked up a clean outboard tank with diesel so I could pressurize the system and found a hairline crack in a vacuum gauge fitting on the top of the Racor fuel filter. This was after the local boatyard had spent several hours (at $90/hr!) changing out filters, lift pump, etc.
 
And you might want to manually see if the stop solenoid lever is moveable . There are threads on here about it. It is what makes the "tink" noise about 5 seconds after turning off the key. if it does'nt go tink, it may not start next time the key is turned. When mine went out on the '05 RTV 900, I crawled under, reached up and moved the lever manually and she would crank right up..I will try to bump that thread, but if memory is good, there is some red paint near the stop solenoid lever . It 's not too far from the oil filler cap but towards the cab.
It would sure be nice if it wasn't the fuel pump at all and just the stop solenoid. Yea, I am probably dreaming but wish it were an easy fix for you.. I start with the easy stuff first. Good Luck !! !! collie

edit: http://www.nettractortalk.com/forums/showthread.php?t=14088&highlight=stop+solenoid
 
Last edited:
That's a lot of good information. Thanks! My problem is that the rack's pin is stuck in a position where it won't clear the notch in the block. I don't want to force the rack over as that might really ruin the pump.
 
AdamsRepair Thank You for your contribution to the forums

I have searched this forum and read many of your older post about the toughness of these Kubotas that you service for the mining industries. could you remark just in your opinion how many hours i could expect out of one with normal service and usage?
 
Injection pump problems

album.php
picture.php
Gummed up from running 70% Biodiesel, then letting it sit without running it for a long time. They run very well on that high concentration of Bio. But it will do this if left for long periods, also is hell on rubber lines.
We have had to clean many of these that were so stuck you swear you would never even get them apart.
 
picture.php


Everything must go back in the hole they came out of. The hard part is making sure the plungers get put back in timing with the rack and each other.
 
aurthuritis said:
AdamsRepair Thank You for your contribution to the forums

I have searched this forum and read many of your older post about the toughness of these Kubotas that you service for the mining industries. could you remark just in your opinion how many hours i could expect out of one with normal service and usage?
Click to expand...
I really don't know!!! I have no reference to one that has not been beat and abused. All I can tell you is some of the problem area's. Like U joints, rear wheel bearing, Shifting and tranny performance problems, cracked heads,, these things are all on top of the list.
 
are the tranny performance problems related to improper adjustment or wear? also what causes the heads to crack?

Thanks
 
aurthuritis said:
are the tranny performance problems related to improper adjustment or wear? also what causes the heads to crack?

Thanks
Click to expand...
Some adjustment issues. But the tranny problems ultimately come from pulling the ramp system (Steep Hills)while over loaded in to high of a gear. Secondly brakes dragging, due to mud and cement building up around the brake lever shaft where it enters the case, and brake cylinders getting sticky from mud sand and cement. They appear to be clean but small amounts of mud works it way past the seals hanging them up. Then the operators continue to run them until they overheat, and stop moving, they pull out of the way let it idle to cool down, them go some more. Pretty much smokes the oil and brass slipper plates, and cylinder faces. Like working for a demolition derby. The water down there eats holes right through the tranny cases. Unbelievable some of the chit we see. Heads cracking due to overheating.
 
knobe said:
Thanks for the photo of the gummed up D902 pump with biodiesel. Is that photo with the delivery valves removed showing the tops of the plungers or is that gummed up area still part of the delivery valve? I never had one of these apart. If the center gummed up area is indeed the top of the plungers, would spraying something like "pb blaster" in there and working the plungers up and down with something like a golf tee help? Or, do I also need to remove those plates (each held on with the torx security screws) to get to the plungers? I would like to see if I can get them to move and possibly then be able to get the rack over to allow the pump to be removed. Those used pumps you have... are they good and how much would one be?
Click to expand...
knobe
In the gummy picture those are the delivery valve needles showing. I found that brake clean is the only thing to work very well on the biodiesel gum. But it takes alot of rubbing also. Just soaking it in cleaner only softens the goo. Under the delivery valve needles are the seats. if you get the seats out you are looking down at the plunger with the slot in it. Those plungers need to rotate with the rack so the slot will line up with the inlet hole for varying the amount of fuel. They are a precision fit and just a little gum won't let the rack rotate them. I use a small magnet to get the delivery valve and seat out. But be warned with the pump still in the block the fuel cam is pushing up still on one or more of those plungers, and by taking the delivery valve nuts loose you take the chance of the plunger cylinder coming up and off of it's locating pin in the body. If it does and you screw everything back down it could shear off the pin then your really boned. So if you have the pump loose in the block but can't get it out of said block, and there is no spring pressure felt against the fuel cam then you should be OK take the delivery valve nuts loose to spray some cleaner in there to try to get the rack to move. DON"T mess with those tamper proof torx they set the fuel delivery for each plunger and have to (should) be set on a pump stand. I can check one of my pumps out if I find a clean one You can have it for $15 plus freight.
 
Thanks again for all your help / advice! I will loosen the pump to relieve the spring pressure and take the delivery valve nuts off and try the brake clean. If I am successful in getting the rack to move and getting the pump out of the block, I will be contacting you about a used pump, if you have one. I do hope I have luck doing this.
 
You must log in or register to reply here.
Top