Please post if the oil change works. I have to think that it is a cpu thing as well??

Also, my coolling fan never seems to come on. Is there a way I can test to make sure the sensor is working. It smells a little hot sometimes...........maybe it's realated? Does your cooling fan come on.

ALso what is your top end speed on this machine?

Thanks.

 

You should take a look in your owners manual, I think that machine is only suppose to use 10w40, not 10w30 or 5w30.

 

owner manul says 5w30 or 10w30.. depending on temps..

so looks like I am withing specs.

Is there anyways to reset that CPU?

also how about synthetic..good or bad choice?

 

There is times on the Rancher AT in auto mode that the transmission control unit will get confused.
What happens is on the crankshaft is a centrifical clutch and centrifical clutch drum. The clutch linings are on the outside edge of the centrifical weights. This assembly drives the automatic tranny unit.
One of the shift points in auto mode is very close to the centrifical clutch weight RPM engagement. When the transmission control unit gets confused, It will try to shift up or down in which may cause the centrifical clutch weights to catch and slip a number of times, going back and forth with the transmision control unit. In short, this can cause the clutch drum to get hot and groove or warp. If the drum warps , it causes the clutch weights to confuse the tranny control unit even more as it dramatically changes the RPM of weight engagement.

A cure ? I have tried simply reinitializing the units the way most Honda Automatics are to be initialized and it does not work. The proper proceedure is outlined in the service manual. The rear wheels are to be removed as the unit is in 2wd mode, and the ECM reset at 21 MPH in 5th gear manual mode. If caught early enough, this will cure the issue you all have mentioned. If the rear wheels are left on during this reset, the transmission will be in a different swash position and RPMS will be different and will conflict once again retaining the issue as it was when the unit came in with the problem. When 400 AT units were uncrated at our shop, I performed this proceedure on them before hitting the showroom floor and this type of issue has not been noted after sale. The proceedure came about with the year 2004 400 AT ECM replacement campain from Honda. It has been incorperated into the later year service manual proceedure for initializing these units.
Severe cases can be noted when riding in auto mode at around 3 to 7 MPH at a steady throttle on pavement, turning and going up a slight incline like a driveway maintaining that steady throttle. The unit will act as the brakes are applied and when acceleration is applied it feels like you are dragging a bulldozer behind you. When they are this bad, the centrifical clutch weights, springs and drum need to be inspected or replaced. I have had units come in that people figured giving it throttle while it is doing this scenario, and holding the throttle, thinking it will cure it. When in reality it has gotten the centrifical clutch so hot that it has melted angle sensors and any wire touching the engine case as well as melted front mudguards next to the engine, and made the cylinder sleeve move up in the cylinder. If your unit does this, do not hold the throttle. Stop, shift to ESP mode and ride it around to let the clutch cool back to normal operating temp. Take your unit to a dealer and have the centrifical clutch drum and weights checked. The drum may be warped or grooved causing the clutch weights to hang up. Replace them and initialize the unit as outlined in the service manual, the problem should not bother you any longer.
One thing that I have found that will burn the clutch drum and parts is if the front brakes are adjusted too tight or the grease that is put on the outer brake drum to backing plate seal has squose out and contaminated the front brake shoes making them hang up, causing the ECM to be confused at the shift point I mentioned above, burning the centrifical assembly out.
If a dealer says they adjusted your clutch on a 400 AT, they are yanking your chain... there is no clutch adjustment on an AT.
I have changed the centrifical clutch weight springs to aftermarket stiffer ones and it changes the whole unit operation in a very good way with no more issues of clutch hang up noted after everything from weights to drum were replaced along with the better springs. I am no engineer, only a Honda tech, but I have noticed springs that have been hot in the clutch go soft and cause the drum to warp from the wrong weight shoe engaugement.

-----gimpster-----

 

i would listen to the man above, he knows more about these atv's then anyone i have met period, i have worked on a variety of quads over the years, but still only know 1/10th of what gimpster does. i'd go by what he says. i'd put money on it....and im a cheap bastard

 

WOW, thanks Gimpster. You da man!!!

That all made perfect sense to me and I'm printing your post.

I just got my '05 400AT (about 4500kms on it) about a week ago from a dealer about an hour and a half form here. Do you think they would have known about this before they sold it to me? Will Honda cover the cost under any kind of recall?
If not, can I perform the repair myself? You said you used aftermarket performance parts.........can you recommend what is best?

Also, I get a hot "smell" coming from the machine. I have only ridden it for about three hours so far but never noticed the cooling fan coming on and it sure throws a ton of heat out. Is there normally a smell from these mnachines when they are at operating temperature?

Again, thanks for the last post!!!!

 

Just print that & give it to your dealer!!!!!!!!!
Thanks for a great explanation!

 

WOW amazing details..thanks so much.

I will investigate this asap and get back to you.

 

I will try keep this short, it's late and I just finished the GSXR engine in my mini-sprint.

Hey little bill, been a while... how ya been my friend ?

There is actually no recall or service campain existing for the centrifical clutch issue. A premature failure found by a Honda tech at the dealership can beb addressed by them to their Honda service rep for approval. Hours and miles on the unit are taken into concideration as for how the issue is handled from there.

The reason I figured it out is for the amount of cattlemem who use these units every day and rely on them. The first one I cured was ridden by a woman rancher who did not ride it rough or hang its lungs out whenever she had the chance. She rode it slow, auto mode checking cattle during calving season. Her drum was warped.

Another case was by a county weed board who carried a sprayer tank on the back. It was overworked and the operator thought he was repairing it by jabbing the throttle when it hung up.

I am **** when it comes to set-up of our new units and make sure they are right before they leave our dealership. Just ask our set-up guys how I get when they miss something...

This is not once again, a campain or recall on the 400 AT. Just my findings and how I have cured the ones that drag down as I described in my first post. I don't need any crap from Honda for starting something.... hehehe

Yes I have found other simple things with them that makes the tranny acting like it is slipping, like low oil pressure, dirty oil, sticking brakes etc... Like I said above, when the unit drags down in AUTO MODE like it is dragging a bulldozer at low speeds and constant throttle is mainly when I look into the clutch.

I tried many spring combos to cure the issue, most I replace get OEM HONDA parts back in them. A heavier spring set is only my preference. Other than that, I will make sure the unit rolls freely when pushed with one hand, toe out, good wheel bearings, slightly loose brakes and clipping 10 coils out of the carb diaphram spring counting the tight ones, Throttle position sensor set at highest ohms in the spec range and then initialize the unit as per service manual rear wheels off at specified MPH, clean air cleaner and fresh diffy fluid. Nothing special is what it takes to make these units into darn good units.
The reason I clip the carb spring is so the venturi does not slam closed so fast when decelerating that it wants to throw you over the bars.

I am not god when it comes to ATV's (I don't wear sandles) I have people who rely on me to keep their daily work unit up to snuff. That is my job.

Other techs who wish to chime in here is welcomed. I am open to the interstate of knowledge and can accept critiszm if need be

I will answer other questions when time permits, it is nearly 3 AM here and I need to get some shut eye before the chickens start barking...

remember, the 400 AT is a good unit. some people expect more from them than they can offer

-----gimpster-----

 

Thanks again Gimpster. Dragging a bulldozer is a great analogy, that's exactly what is happening to mine.



I will contact the dealer today.