Adjusting idle speed

Tact · Jun 12, 2006

My neighbor just bought a '06 RTV and I noticed that his idle speed on his RTV is so much lower than mine, which is a '04. His sounds so much better with the lower idle and you can actually talk to each other while it is running.
How can you turn the idle speed down without effecting the performance? Any help would be greatly appreciated.

doggman · Jun 12, 2006

I asked the same question in a May 11 posting. We never did get to the bottom of the problem. At least you can see what didn't work for me regarding the idle issue.

bczoom · Jun 13, 2006

Sorry guys.

I can't seem to find the correct answer to this question. I'll dig more today when I get a bit of time.

Brian

Tact · Jun 13, 2006

Here's the solution to turning the idle speed down with out effecting performance. On top of the fuel pump, which is located on the passenger side, there are three 10MM bolts setting on top. The bolts are staggered and each point in a different direction. They are all tied with safety wire as you can see in the picture. The bottom bolt needs to bebacked out approx. 3/4 to one full turn. You can't actually see the correct bolt in the picture, it's hidden by the camera angle. You need to do this with the engine off or you'll get bit by the fan. Mine idles so much better and no loss of performance. Very easy fix.

bczoom · Jun 13, 2006

Thanks Fred,

I always thought my idle was OK but maybe I'll go play with it a bit to see what happens.

Brian

Tact · Jun 13, 2006

Brian,

After I made the adjustment I called the dealer and they told me they received a bulletin from Kubota instructing them to turn down the idle on all their machines. I personally like the reduction in the loud idle but now I'm curious to see if the pump can be turned up a bit. Do you know how this would be done? I've heard with a slight adjustment you could gain 3-4 hp, maybe just enough increase to get up some steep hills that couldn't be achieved previously.

Guest · Jun 13, 2006

Hey, thats great! Thanks for the picture and good explination.

bczoom · Jun 14, 2006

[quote user="Tact"]but now I'm curious to see if the pump can be turned up a bit. Do you know how this would be done? I've heard with a slight adjustment you could gain 3-4 hp, maybe just enough increase to get up some steep hills that couldn't be achieved previously.[/quote]

First, a word of caution... Being as there's tamper-proof caps over this cover, I believe Kubota doesn't want these adjusted. Do this at your own risk. If you're still on warrantee, I wouldn't do it at all.

Well, I have to go from memory here as the instructions were given to me verbally over a year ago.

On the rear of the injector pump, there's a cover with tamper proof caps over the nuts.
Remove the caps and take the nuts off.
Inside, there are 2 adjustment screws.
I "think" you turn the lower one in about 3/4 of a turn. Play around with them but remember (better yet, write down) the initial settings so you can revert back if/as necessary.

Brian

doggman · Jun 16, 2006

Brian has a good point to write down the adjustments that you make to the fuel pump and governor. 

You can really screw up the performance of a diesel engine if you get the governor settings out of whack. The governor is the "brain" of the engine, and in essence, senses the load and increases or decreases the fuel delivery as required to keep the RPMs from "drooping" too much. 

What happens if the governor is out of whack? You can get surges in power (when you don't want them), lack of power across the board or in certain ranges, RPM hunting (the engine RPMs cycle up and down likethey are hunting for an idle point), overfueling (blackstacking), underfueling, bad throttle response, etc., etc.,. You get the point.

bczoom · Jul 14, 2006

I was going to turn mine down last night but had a couple questions.

After lowering the idle, how did the hyd. lift for the dump bed work? Do you need to idle it back up to get it to dump? Empty and/or box loaded.

Also, has anyone adjusted it down and then run it in a cold environment? I'm wondering if it'll need to be turned back up for the winter.

Tact · Jul 14, 2006

Brian,

After turning mine down the bed still lifts as it did before, no change. I can't say what it will act like in cold weather yet. It's 96 degrees right now.aaaaahhhhhhhhhh[

]

andrewbph · Jul 14, 2006

I have also turned down the idle and the dump work just as before. Likewise, I'll will find out this winter it it effects the cold performance. Also turning the idle down increased the shifting ability alot and the noise was reduced as well. Very glad to have found the advise from this forum.

ajdillon · Jul 14, 2006

I tried turning my idle down and it ran pretty rough, pulsating badly until I turned it back up to the point I started at. Maybe my idle was already set lower, but it's still pretty noisy.

Andrew

Tact · Jul 14, 2006

[quote user="ajdillon"]

I tried turning my idle down and it ran pretty rough, pulsating badly until I turned it back up to the point I started at. Maybe my idle was already set lower, but it's still pretty noisy.

Andrew

[/quote]

Are you sure you are turning the correct screw? The correct screw is hidden in my picture at the bottom of the thread, so you can't actually see it. Again, there are three screws, all pointing in a different direction,and the correct one is on the very bottom, somewhat pointing toward the steering wheel.

bczoom · Jul 16, 2006

I turned mine down. I like it.

Andrew - To make sure you're adjusting the right one, make the adjustment with the engine running. If you're fingers get caught in the fan, you're doing the right one. Don't ask how I know... Fred warned me but I did it anyway. Just glad the fan is plastic.

Tact · Jul 16, 2006

[quote user="bczoom"]I turned mine down. I like it.

Andrew - To make sure you're adjusting the right one, make the adjustment with the engine running. If you're fingers get caught in the fan, you're doing the right one. Don't ask how I know... Fred warned me but I did it anyway. Just glad the fan is plastic.
[/quote]

Hehehehehehe[

]

bczoom · Jul 17, 2006

[quote user="Tact"]The bottom bolt needs to bebacked out approx. 3/4 to one full turn. You can't actually see the correct bolt in the picture, it's hidden by the camera angle.[/quote]

Hmmm. I just re-read this post.

The bolt I backed off is the the one that's visible with the head pointing to the 1 o'clock position (the head closest to the fan). Is that the one you adjusted?

Tact · Jul 17, 2006

[quote user="bczoom"][quote user="Tact"]The bottom bolt needs to bebacked out approx. 3/4 to one full turn. You can't actually see the correct bolt in the picture, it's hidden by the camera angle.[/quote]

Hmmm. I just re-read this post.

The bolt I backed off is the the one that's visible with the head pointing to the 1 o'clock position (the head closest to the fan). Is that the one you adjusted?
[/quote]

That's the one. Of the three, it's the bottom one. I love the way mine idles now and no loss of power. I too am wondering if there will be a difference in cold weather this winter.

Tact · Jul 17, 2006

Brian,

Now that I re-read your post again, I don't believe the correct bolt is visable when looking from the side of the RTV, and if you were adjusting the correct one while the engine was running you might be missing a finger as it is very close to the fan. Just make sure it's the bottom screw(bolt) of the three.



Fred

bczoom · Jul 17, 2006

[quote user="Tact"]and if you were adjusting the correct one while the engine was running you might be missing a finger as it is very close to the fan. Just make sure it's the bottom screw(bolt) of the three.[/quote]
Nah... the fan is plastic. Makes a lot of noise when you're finger hits it but even after getting nicked, there was no blood.[

]

I'll look again but the one I adjusted made it idle nicely.

Adjusting idle speed

Member

Member

Senior Member

Member

Senior Member

Member

Guest

Guest

Senior Member

Member

Senior Member

Member

New member

Member

Member

Senior Member

Member

Senior Member

Member

Member

Senior Member