Air dryer freeze up and other problems

[BenRoberts]

Probably the ppv on the truck freezing up. See if the horn and wipers work when it's building over pressure. The governor is past the ppv so if it's frozen then the governor can't do its job.
Will

I will do that. Not to sound dumb but ppv stands for. The mrap dryer you sold me is a huge improvment over stock. I do appreciate it.

 

[BenRoberts]

You're in OH? That is GR's and a few other's stomping grounds. You'll need to be changing your avatar pic every 3 weeks, it is a requirement of the OH members.

Hes about 20 30 min south of me. helped me over the phone before. Great guy.

 

[gimpyrobb]

Pressure protection valve

 

[Suprman]

In the area of the air tank drains but in and under a bit. Common failure item.

 

[BenRoberts]

so when it over pressures and the wipers dont work theres a good chance that valve is toast? first things first the alternator needs fixed.

 

[BenRoberts]

While I have all these questions going i got one more. You guys have a coolant preference? I once heard an additive had to be added to the coolant but didnt know if that was true or not. when I topped it off I added yellow add to anything coolant.

 

[Jericho]

I use Napa brand fleet guard down to -45 . works for me !

 

[Cape Coastie]

I agree with Suprman. I had the same symptoms and found the answers on this site. Ordered one on line and installed. I checked the pressure before I installed it am was glad I did. The pressure is adjustable and it was set way to high. I set it at 60psi and everything returned to normal. It is located on the passenger side of the truck by the air tanks. The photo is looking aft. Hope this helps.

 

[big block 88]

I just run a 50/50 mix of prestone. Havent had any issues yet.

 

[Jericho]

I haven't seen a 900 series 12 volt heater element. Its a two min trouble shoot mine is 24 volt

 

[exssdru]

Truck was likely shut down in wrong switch order, and zapped the alternator and ABS module. Welcome to the club. Your alternator is probably not working anymore. I sell replacements that do not have the failure characteristics of the stock one, for reasonable prices. You can also get a Chinese one for $110 shipped to your door, but I don't offer them. Or you can replace it with stock and go through it all again.
Air leaks are pretty much search-and-destroy type issues.

What is the correct switch order? Any help for the new guys is always appreciated.

 

[Swamp Donkey]

this all may be stemming from a low voltage situation. I have a love hate relationship with this truck

You are correct about low voltage. And all these systems are interconnected through the PCB in some way or another. Low voltage and charging issues can cause a whole lot of symptoms across the board. The ABS system is voltage sensitive and will throw a light if voltage is too high or low. This is most likely a symptom though, not the cause. Does the ABS system self check when you start the truck?

Another possibility is that your PCB is not working all the time. The exciter wire for the alternator in stock form runs through the PCB. If the PCB works intermittently while the truck is running, the alternator will do the same. Would explain your gauges going crazy at random.

If voltage becomes low then the solenoids inside the PCB have trouble holding closed, compounding the problems further. The heater for the air dryer is powered by one of the solenoids in the PCB. All these things run through that box. And all can be symptoms of a failing PCB when they show up together.

I've been down this road when I first got my truck, with multiple symptoms popping up all at once. I manually charged the batteries and replaced the PCB. Everything went back to working properly.

Whether or not your alternator is truly failing, 74M's upgrade is great peace of mind. The factory alternator is flakey at best. You'll have to do some tests to see if it's truly the issue though. A new alternator won't fix a failing PCB.

The fact that your air dryer is purging means that it's mechanically working even if the heater is not. It is just a slave to the system and can't cause an over pressure, even if it fails to purge. The burst of air is only to remove moisture and has nothing to do with cut-out pressures. You could remove it from the system completely and straight pipe all the lines but the system would still work fine, although you would be retaining moisture. The PPV is most likely the cause as Suprman pointed out. If the PPV doesn't open properly then the governor never sees system pressure to cut-out the compressor.

 

[Swamp Donkey]

What is the correct switch order? Any help for the new guys is always appreciated.

Bottom switch first. When engine stops turning, the top switch can be turned off. Engine off then Power off.

 

[Ford Mechanic]

Your not the only one with over pressure issues due to the ppv when around freezing. I replaced mine less than a year ago and I'm good about draining the tanks. Still happens at times.

Sent from my SM-G900V using Tapatalk

 

[gimpyrobb]

While I have all these questions going i got one more. You guys have a coolant preference? I once heard an additive had to be added to the coolant but didnt know if that was true or not. when I topped it off I added yellow add to anything coolant.

DO NOT ADD ANY ADDITIVE until you test your coolant! Too much or too little is bad. Its called DCA diesel coolant additive. Do a search on google to see what needs to be done, I am not too familiar to say with any certainty.


http://www.acustrip.com/sca.html

 

[Andrmorr]

Bottom switch first. When engine stops turning, the top switch can be turned off. Engine off then Power off.

Yep...an old saying to remember operating switches in right order was:

UP-UP
DOWN-DOWN

This meant that to start truck, turn on upper switch first then lower
To stop truck, turn off lower switch first then upper
worked well when new GI's had to recite before switch movement...

 

[74M35A2]

It is a stupid design. Nothing should be that sensitive. Should have just been a single ignition switch that does both. Alternator replacement with anything other than stock aleviates this issue completely. I shut my truck off in the "wrong" order now just because I can with no over-volt. Don't have to be picky anymore about somebody else doing it.

 

[98G]

It is a stupid design. Nothing should be that sensitive. Should have just been a single ignition switch that does both. Alternator replacement with anything other than stock aleviates this issue completely. I shut my truck off in the "wrong" order now just because I can with no over-volt. Don't have to be picky anymore about somebody else doing it.

That's ingraining a bad habit that'll bite you when you operate someone else's truck....

Next time you need to pull string, I won't let you use mine....

 

[Tinstar]

I cannot say it enough that I should have upgraded the alternator sooner.
With the new 100A alternator, I now have piece of mind and a better truck.

 

[74M35A2]

That's ingraining a bad habit that'll bite you when you operate someone else's truck....

Next time you need to pull string, I won't let you use mine....

Not really. It is just making a badly designed system correct like it should have been from the beginning. If they would have placed the battery disco switch elsewhere in the truck like other vehicle makers do, this would not be such an issue. By upgrading the starter and alternator to modern parts, I eliminated 1/2 the PCB and and the over-volt issue entirely. The ABS, CTIS, and PCB will live happily ever after. *The End*