Rtv excessive black smoke and loss if speed

aurthuritis

Well-known member
Site Supporter
before you tear into it you should confirm as you have partially done.
1.there is no obstruction to the air intake or filters.
2.correct valve setting.
3.there isn't a condition of parasitic load causing lugging.
4. that the smoke is indeed unburnt fuel and not a re circulation and burning of engine oil through the crank case vent system.
 

Ngwarrington

New member
I checked transmission fluid levels and it doesn’t even read on the dipstick but I can see it in there. Is there a good chance this has something to do with it. It blows Black smoke while in neutral on starts and just reving it. I tried turning the screw in and out it didn’t change the black smoke at all.
 

bordercollie

Gold Site Supporter
Gold Site Supporter
How much sudt did you put in the transmission when you changed the 2 filters? My 2011 rtv 900 called for- I think- 2.6 gallons or thereabouts. What year model is this machine because some year models had a weird transmission fill port location . Yellow filter is on the passenger side .
 

aurthuritis

Well-known member
Site Supporter
there are two dipsticks. one in the tank reservoir for the HVT part of the drive and another in the gear case/differential case.

as far as the fuel delivery there is something i forgot to mention. part of the fuel delivery amount is also controlled by a number of shims between the pump and engine block. more shims = less fuel and less shims = more fuel. this will also affect timing but mostly negligible. there is also a very very remote possibility the injection timing is out but like i said that would be a very very very remote possibility. the fact that turning the fuel screw has no affect and has been tampered with leads me in the direction that is a good place to start.

i would care fully remove the injection pump and see if the delivery screw is even connected. look for the spring. and confirm the amount thickness and presence of shims. after you confirm there isn't any parasitic load. you need a dependable tach???
 

Ngwarrington

New member
I pulled IP and all spring and hardware are intact and good pressure on all pistons. There are 6 shims there. I checked all valves (intake valves had play while exhaust valves were beginning to rise).
 

hondajoe

Member
Black smoke

Well from what I have read all good advice.I think the old Kubota got a load of gas.The pump is probably stuck that's why the adjustment screw don't work. I would think it has a advance also stuck in advanced state not sure about that though.That might be why its loud.JOE
 

aurthuritis

Well-known member
Site Supporter
place the machine in a stall with engine rpm max. you may need to put some weight in the back and place on a good tractive surface or use the brakes. don't do a stall test with engine and transmission cold. warm up the transmission oil first. you will need a dependable tach. i don't have a book for your model so you will have to ask for the stall speed for your engine and model.
 

v10rick

Active member
Site Supporter
My RTV was overheating when climbing hills. After performing the necessary repairs (replaced the head) I butt the RTV against a tree and mashed the accelerator in high gear.

Old head=full scale temp reading and loosing coolant, new head=1/3 scale reading and no coolant loss.
 

Ngwarrington

New member
Having a mechanic check valve clearances and a compression test. Will report results. I think I’ve done everything I trust myself doing without wasting money and time.
 

Ngwarrington

New member
Sorry been awhile i ended up getting new injectors but im still experiencing the same issues . Entire fuel system has been gone through. Having a mechanic take a look now.
 

Ngwarrington

New member
Ok long time since i touched the machine. Finally pulled the head and no visible problems with gasket or head. BUT i did just now see that there is a new valve train hold down piece where the bolts goes through, then realized that there is 1 out of 6 valve caps which the rocker arm rides on top of. This has got to be part of the issue???
 

California

Super Moderator
Staff member
Site Supporter
...just now realized that there is 1 out of 6 valve caps which the rocker arm rides on top of. This has got to be part of the issue???
Like an umbrella over the top of each valve spring, and 5 of 6 are missing? That might account for oil running down the valve stems.
 

Ngwarrington

New member
Like an umbrella over the top of each valve spring, and 5 of 6 are missing? That might account for oil running down the valve stems.

The seals under the the springs were still there and intact, it was the cap on very top of the valve that the rocker arm rides on to open and close valves. Im just waiting on kubota to call when parts come in. In the mean time is there any literature about setting the fuel adjustment back to factory?
 
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