lets strike a nerve.

[bvfdfire]

the ac control head, always resets every time the machine is killed or started, upon start up the controller will go to mid temperature range, fan will go to floor discharge and circulation goes to outside air, and all ac controller functions blink. if i immediately cycle the temp control to cold discharge, it will allow me to change the circulation to inside only, and i can direct the air to back of operator discharge. this will let the air system cool and it works very well for a few minutes then it starts to cycle through upper cab blowing to lower cab blowing, then the temperature will start the the same cycle, going from max cold to max heat. its as if it has a thermostat that has gone awry,the system will come back to cold air eventually but it wont stay there. from what i have been able to find from mechanics that are way more familiar with this system than me is that the control paths are so voltage sensitive that they are easily misguided by dirt build up and possibly moisture tracking. i recently had the seat out so i could rebuild it and cleaned about 3" of dirt out of the floor, (from the predecessors). if i can figure out the voltage, perhaps i can fix it or figure a way to simplify it down to where i can fix it.

 

[CatKC]

I assume the AC never settles down even after running for a while.
If you have a wiring schematic it should show what sensors there are for controlling air flow and temperature.

 

[Tinkerer]

perhaps I should have tried that approach. I have found that the air conditioning system that the Case track hoe that I asked about is in fact built by Denso, and I'm down to chasing millivolt amperage across the control board since it appears that the issue may be there.
And yes, I have gotten a lot of valuable information from the senior posters on here, and I built my own line boring systems with some advice (re lots of advice. But I have in fact, done what the title of my post says and have "struck a nerve".

You determined you had a Denso unit in the hoe and didn't come back and share that information. At least I didn't see where you did. If you had, the help you wanted was evidently here from members more than willing to help.
My pet peeve is when someone comes here, gets help and then don't have the courtesy to let us know the outcome that may help others reading the thread. I see this happen over and over again. You didn't strike a nerve with me. I am just dismayed and amazed after all these years that I would see a thread titled "Lets Strike a Nerve" for the reasons you posted.

 

[bvfdfire]

im about to order a service manual, so that i will have access to a schematic, and perhaps a troubleshooting tree. i agree that it is virtually impossible to trace anything without those paths. I wholly agree with you about posting the results of the help received from these forums. As you point out, others can learn from reading the outcome of the others that have had issues.

I assume the AC never settles down even after running for a while.

It continues to perform its round house functioning, making it a nuisance to run since you have to run the doors open, because of the temps. Yes, we've gotten spoilt to the ac, but hey I think I should make it work since its got it.

 

[Tinkerer]

For all the 9040B owners needing information, I found this on eBay for less than $30.00. Here is a link to it.
----> http://www.ebay.com/itm/Case-Crawle...061018?hash=item212135491a:g:~98AAOSwSlBYsGVa

 

[CatKC]

With all those 'strange symptoms' you -must- get a schematic to repair it unless you want to 'bypass' all the 'fancy controls' and just hook up the AC as a basic on/off operating system.

 

[Hydraumind]

Good morning .
It's summer. I don't spend that much time on HEF as I do in the cooler months.

A line first post of this thread did hit a nerve.
"to the masters that used to frequent here. you are missed, to the ones that refuse to share anything, thanks,for nothing."

I'm not a power poster, but I have offered up advise on several occasions. It is usually well received.

While I would never, ever think of putting myself in the same bracket as people like Cmark, Nige, kshansen, TCtractors, I do have a certain skill set that 45 years of being on the business end of a set of wrenches will do to you.

Yesterday there was another post that got my back up, a comment that there are no good mechanic's.

This "good" mechanic is getting a little sick and tired of people asking for free advice and not liking what they get.

So far I have removed myself from 4 RV forums. I got sick of back yard mechanics trying to override my advice telling me that I have no idea how their motorhome works, because I do not own the same one.

I have removed myself from the GM forum, mostly because of the internal bickering and political agenda's

I come here for a good read, I follow certain threads and on occasion I will offer my 2 cents worth of knowledge, and now I am not sure if I even want to do that anymore.

This is a great forum, ask your questions and be patient.
Don't insult people, you will get better responses.

Yes indeed you are a good mechanic. I really like how you put things together