New Owner! Bought cheap RTVx1100c, have to deal with engine issue.

[gimbal]

Hi All,

Thought I'd share my developing story.
I bought a 2020 RTV 1100, it's smokey and underpowered. I'm not too surprised by this, I knew the risk buying low at auction. Disappointed, but that was the risk I took.
I checked the basics, filters, etc, still very smokey. Less smoke at start than after running a while.
It has 900 hours, and it has a turbo installed. Unit looks good other than the engine issue, everything else works, not too rusty.
The fluids are all at correct levels.
No bubbling in coolant, or emulsified oil that I can see.
I don't see much blow-by at the breather or oil fill cap.
I cracked off the injector lines, and one and two act as you would expect, causing a stumble, but number three does not (I'm counting #3 as the one closest to the rear of the machine). When you crack the number three fuel line at the injector, there is no change in the running, but the smoke decreases a lot.
I swapped the #2 and #3 injectors, and the problem is still in #3. This rules out the injector.
About to do a compression test, but I don't have the right fitting for the glow plug hole yet.
I'm expecting to find adequate compression in 1 & 2, but low on three.
Maybe the head gasket, valves or a cracked head? Rings? Bent Conn Rod? Hole in Piston?
I'll get the compression test tomorrow or the next day. I'm ready to pull the head off if compression is low, to see what I can see.
If its possible to change a piston in frame, I'm game to go that far, but if the whole engine needs to come out, I'll take it to the dealer or other mechanic.

Has anyone here changed a piston in an RTVx1100c with the engine still in the vehicle? Is it possible? Any advice?

 

[Smilingreen]

Good luck with your endeavor. Do you have a small illuminated bore scope you can look around inside of the cylinder with? Probably would help you narrow things down. You have eliminated the injectors, but have you looked at the injection pump? If you had a hole in the piston, I would think you would be getting some major blow by. How does the oil look? Does it smell heavily of raw diesel fuel?
That new of a machine, with an after-market turbo thrown on it, sold at auction, would make me wonder how bad the previous owner beat the machine.

 

[Smilingreen]

Another thought: What elevation do you live at? I have read that the Kubota diesels are pretty smokey at higher elevation. Is the smoke white, bluish tint or black? Have you tried pressure testing your radiator, to see if the head gasket is leaking a small amount of coolant into the cylinder?

 

[gimbal]

No boroscope, unfortunately. I'm considering getting one. Yeah, didn't even know it had a turbo till it showed up! Oil does not smell of diesel. My current thought is that it likely has a bent rod, since I'm not seeing a bunch of blow by, which I think I would if there was a ring/cylinder issue, a valve guide issue, or a piston hole. You're right, I didn't rule out the fuel pump, but I did get the compression test done yesterday, and cal 3 is low compared to the other two.

I'm at very high altitude, 10k feet, but it's definitely not from just that or from coolant, and you can smell that the smoke is from diesel and the power is way down, it will drive, but not well. I didn't pressure test coolant circuit, because I found the low compression in the one cylinder. I also put some oil in the cylinder and tried the test again, and the compression came right up. I'm feeling pretty confident that the issue is loss of compression due to ring/cylinder wear now, but am surprised that there isn't a bunch of blow-by.

 

[gimbal]

Well, I ended up replacing the engine with new from Kubota. I considered fixing it cheaply, but was running out of good weather, and I've been traveling quite a bit, so hard to fit in the project. Paid plenty, but hopefully I'm in a good reliable state now! The #3 cylinder had very low compression, and the shop could see that the cylinder walls were heavily scored. They diagnosed it as a bad wrist-pin or bearing.

 

[Doc]

Sounds good. Seems you will still end up with a nice 2020 1100 for a bargain basement price.

 

[v10rick]

Well, I ended up replacing the engine with new from Kubota. I considered fixing it cheaply, but was running out of good weather, and I've been traveling quite a bit, so hard to fit in the project. Paid plenty, but hopefully I'm in a good reliable state now! The #3 cylinder had very low compression, and the shop could see that the cylinder walls were heavily scored. They diagnosed it as a bad wrist-pin or bearing.

Used replacement engines are scarce for the RTVs. Rebuilt units are close to the price of new, when including the core and shipping costs.
That new engine should last a very long time, with proper maintenance.

 

[gimbal]

Used replacement engines are scarce for the RTVs. Rebuilt units are close to the price of new, when including the core and shipping costs.
That new engine should last a very long time, with proper maintenance.

Yeah, I just bit the bullet. Hoping it works well, this is all a bit of an experiment, but it's turned into an expensive one! This is going to replace a Honda Pioneer, mainly used for cold weather. Looking forward to better Defroster and the enclose cab in the winter. It's pretty extreme winter conditions at our cabin, it was completely buried last year! Fingers crossed that it does the job well enough for us - we are at very high altitude.