m35a3 air diagram?

[bigflew]

Can anyone tell me if there is a diagram of the air system on an a3 deuce?
I have done a serch and dowmloaded the TM and cant find

 

[AceHigh]

Someone posted one on m35a3.net in this thread:

http://www.m35a3.net/forum/index.php?topic=212.0

It is from TM 9-2320-386-24P page 0114? Maybe.

 

[glcaines]

There are several diagrams of the pneumatic system for the A3 in the TMs. They are very confusing to follow, however. I found that using different colored highlighters for the different circuits really makes it easier to follow and understand. Look in the TMs under brake system, compressor, etc. The system is actually very simple once you figure it out.

You must be having a problem if you need to look at the schematics of the compressed air system. What is the issue?

 

[bigflew]

problems are ctis manifold continuis dumping air at times(most of the time) stoped when unpluged controll unit.
also steering assist drag link air blowing by not just when you turn.
what pg or section were the diargams?

 

[glcaines]

Are you sure it's the CTIS manifold blowing the air and not the dryer or the relief valve? I thought the same thing, but it turned out to be a faulty air dryer blowing the air, along with the emergency relief valve. I found a complete replacement NOS dryer unit on Ebay for a very good price, which solved most of that problem. i also ended up replacing the unloader on the compressor. The unloader was leaving the compressor running when the tanks were full and then the emergency relief valve was operating. I also had a similar problem with the steering dumping air, but mine was mostly when i turned close to full either direction, but sometime it did it without turning. I jacked up the front of the truck so the front wheels were off the ground. I then removed the air inlet from the steering actuator and put in several large squirts of air tool oil. I then re-attached the air supply, fired up the truck, and turned the steering wheel full left and then full right for about 50 times, until the problem went away. i havent had any issues with the steering since.

 

[Rustygears]

The air system is best troubleshot by isolating it as best as possible. The first thing to do is to close the steering assist valve located at the engine firewall near the center of the truck inside the engine compartment. It is a petcock, like a radiator drain, and brass. This will isolate the air operated items like the steering and engine cooling fan control. Next, check the air dryer for continuous venting. There is a safety valve at the dryer as well as at the engine (if MWO applied). Confirm they aren't open. Confirm compressor governor ($20) is working properly. If you still are loosing air (CTIS turned off), you have a plumbing leak. On my truck, there was a leak at the fitting where the system transitions from copper tubing (from compressor) to plastic tubing. All it took was tightening that and a few others to make the system air tight. I found the air assist steeing regulator was leaking badly, by isolating with the valve as indicated. with that fixed, I found air assist drag link leaking and some marvel mystery oil fixed that. I found that the dryer wasn't drying because it was cloogged with snot from being cycled too often due to leaks. I replaced the filter and dessicant cartridge for about $50 and haven't had moisture in either air tank since. It just takes a methodical process to peel all the layers of the onion. I'll bet your truck has a few of these simple issues as well.

The air system diagrams are in the A3 TM, in the back.

 

[bigflew]

I took the drag link apart as much as i could (prety much the ends} and found a rubber gasket torn (most likley to keep moisture out) made new one and put oil in all fittings steering seems to be working better not blowing by so far.
Im pretty shure it was the ctis manifold dumping air but will check again in morning.
is ctis at all dependable or should it be bypassed ?
THANKS FOR ALL THE HELP

 

[Rustygears]

If the CTIS is shut down it shouldn't leak air. There is only 1 heavy duty selenoid valve that lets air into the system. If you think it's leaking, I'll bet it's one of the press fit plastic tubing connectors. The tubing works loose and/or the fittings crack.

 

[glcaines]

Unfortunately, the CTIS system gets blamed for a lot of problems caused by other systems. It is actually an amazingly simple system once you start looking at the different components internally.

 

[autigers35a3]

Part number/soruce when you replaced your air dryer?
Or is a easy match at NAPA etc...?
Thanks...

 

[AceHigh]

It is a standard Haldex off the shelf item. Truck parts places have them, my Napa does not.

Eriks has the whole thing or parts:

Air Dryer For M35A3, 12450212 / Haldex "Pure Air Plus" DA33110X / N4250B

Here is the picture from Erik

 

[bigflew]

air is definetly blowing by at ctis manifold and only when controll unit is pluged in. also controll unit does not power up most of the time.
Im thinking controller is bad.
as far as the steering leak im having to put oil in the drag link every morning or ain is continuisly going through it.
Anyone parting out an A3?

 

[Pajaro]

Can I get some advice on the cooling fan?

I have a 95' M35A3 cooling fan issue. It appears there is an air driven clutch or motor on the fan hsng, however the fan speed never increases other than with engine RPM's. It gets up around 240 degrees at times and it seems to me the fan clutch shouild increase the air flow. Am I thinking right? How can I t-shoot the air valve/solenoid?

Thank you for any help.

 

[glcaines]

The fan only turns as fast as the engine RPMs, never faster. If the clutch is not engaged, the fan will still turn, albeit much slower than the engine RPM. Are you sure the fan clutch is actually engaging? Read the TM and it will advise you on how to troubleshoot. It is a very simple circuit.