Title: D2 Governor
Post by: Peter on February 20, 2021, 06:56:20 pm
Post by: Peter on February 20, 2021, 06:56:20 pm
In reading the D2 Governor is tied to the front and rear air brakes, if I am reading things right.
There has been a lot of talk about PSI reading in the 130 range, and my front reading when
fully warmed up is about 100 in the front and with the rear reading around 110. Is this normal or should i they be higher through adjustment?
It is my intention to purchase two of these, one to install immediately and one to keep as a spare.
Can anyone advise what the install procedure should be...ie: Do I dump all the pressure first before removing lines etc
If anyone here could provide me with a "coles notes" edition on how to go about he install it would appreciated
There has been a lot of talk about PSI reading in the 130 range, and my front reading when
fully warmed up is about 100 in the front and with the rear reading around 110. Is this normal or should i they be higher through adjustment?
It is my intention to purchase two of these, one to install immediately and one to keep as a spare.
Can anyone advise what the install procedure should be...ie: Do I dump all the pressure first before removing lines etc
If anyone here could provide me with a "coles notes" edition on how to go about he install it would appreciated
Title: Re: D2 Governor
Post by: craneman on February 20, 2021, 07:21:12 pm
Post by: craneman on February 20, 2021, 07:21:12 pm
The governor is tied to the wet tank and supplies whatever pressure it has been set for. 90/120 is usually default. It can be reset to 100/130 which helps when airing tires. The front tanks should read the same when the governor shuts off.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 20, 2021, 08:29:59 pm
Post by: Chuck & Jeannie on February 20, 2021, 08:29:59 pm
As Chuck (craneman) said, when your air dryer purges (blows off) and your compressor cuts out (stops pumping) both of your dash air pressure gauges should read the same pressure. Your gauges are reading different pressures. This may indicate one (or both) of your pressure gauges not reading the correct pressure. Your gauges are probably electronic (instead of mechanical). There are informative threads on the Forum discussing this subject. Search for the term "blue module" for more information.
If your system air pressure really does top out at 100-110 psi then this is lower than normal. Normal is 120-130 psi. It is possible that your D2 is plugged up with junk inside and not properly controlling the air compressor. Installing a new D2 is a inexpensive way to eliminate this problem.
D2 installation is not complicated. Before you do anything make careful note of any air lines connected to the D2. Draw a diagram if necessary so that you are sure the lines will be reconnected properly to the new D2. If you have any pressure in your wet tank release it by opening the water drain valve. If the check valves on your front and rear brake tank inlets are holding your dash pressure gauges may still show pressure when your wet tank is empty...this is a good thing! Don't worry about it.
Remove the old D2, clean any dirt and grease off so you can see all the ports on it. The new D2 will come with some pipe plugs. They should have thread sealant on them - DO NOT use teflon thread tape on the plugs. Put the plugs in the new D2 in exactly the same place as where they are in the old D2. Swap any air line connectors on the old D2 over to the new D2. Use a little thread paste on the connectors. (See links below) When you get the new D2 ready to mount, it should look identical to the old one.
Permatex High Temperature Thread Sealant Permatex (https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant/)
Amazon.com: Loctite 483631 592 Thread Sealant, 6-Mililiter Tube: Automotive (https://www.amazon.com/Loctite-37398-Thread-Sealant-6-Mililiter/dp/B0002KKTHC?ie=UTF8&tag=foreforums-20&linkCode=as2&camp=1789&creative=390957)
Then all you have to do is bolt the new D2 in place and reconnect the air lines. DONE! ^.^d
https://www.youtube.com/watch?v=FHGcXvDmZ5E
If your system air pressure really does top out at 100-110 psi then this is lower than normal. Normal is 120-130 psi. It is possible that your D2 is plugged up with junk inside and not properly controlling the air compressor. Installing a new D2 is a inexpensive way to eliminate this problem.
D2 installation is not complicated. Before you do anything make careful note of any air lines connected to the D2. Draw a diagram if necessary so that you are sure the lines will be reconnected properly to the new D2. If you have any pressure in your wet tank release it by opening the water drain valve. If the check valves on your front and rear brake tank inlets are holding your dash pressure gauges may still show pressure when your wet tank is empty...this is a good thing! Don't worry about it.
Remove the old D2, clean any dirt and grease off so you can see all the ports on it. The new D2 will come with some pipe plugs. They should have thread sealant on them - DO NOT use teflon thread tape on the plugs. Put the plugs in the new D2 in exactly the same place as where they are in the old D2. Swap any air line connectors on the old D2 over to the new D2. Use a little thread paste on the connectors. (See links below) When you get the new D2 ready to mount, it should look identical to the old one.
Permatex High Temperature Thread Sealant Permatex (https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant/)
Amazon.com: Loctite 483631 592 Thread Sealant, 6-Mililiter Tube: Automotive (https://www.amazon.com/Loctite-37398-Thread-Sealant-6-Mililiter/dp/B0002KKTHC?ie=UTF8&tag=foreforums-20&linkCode=as2&camp=1789&creative=390957)
Then all you have to do is bolt the new D2 in place and reconnect the air lines. DONE! ^.^d
https://www.youtube.com/watch?v=FHGcXvDmZ5E
Title: Re: D2 Governor
Post by: Lon and Cheryl on February 20, 2021, 08:59:47 pm
Post by: Lon and Cheryl on February 20, 2021, 08:59:47 pm
My brake performance had a notable improvement when I replaced my D2 and adjusted the pressure from previous 120# to 130#.
Title: Re: D2 Governor
Post by: jbeem on February 20, 2021, 09:11:43 pm
Post by: jbeem on February 20, 2021, 09:11:43 pm
My front and rear air tanks had a 10 psi differential. I replaced the check valves on inlet side of the air tanks and afterwards my pressure between the two tanks were the same.
Title: Re: D2 Governor
Post by: Dave Cobb on February 23, 2021, 08:51:30 pm
Post by: Dave Cobb on February 23, 2021, 08:51:30 pm
It's easy to change I found if, I loosen the airlines before unbolting the D2 from the coach frame. Then follow those instructions and plug the correct holes. Then with the airlines at least finger tight I then remount the D2. Then tighten the hose connections.
Title: Re: D2 Governor
Post by: Spiderhitch on February 23, 2021, 09:08:43 pm
Post by: Spiderhitch on February 23, 2021, 09:08:43 pm
Where is the D2 located on my coach. My brake gauges show 100# on dash. Just replaced 2 leaking tank drains, 2 safety valves and check valves.
Title: Re: D2 Governor
Post by: Hach on February 23, 2021, 10:54:49 pm
Post by: Hach on February 23, 2021, 10:54:49 pm
So funny. I recently replaced the tires on my 2004 36U295 and the front tires spec out to require 115psi given my weight. Now my air pressure only went to 112psi so I was always dreading that last 3lbs. Played games with my wife stomping on the brake to engage the compressor and trying to time it just right. Then I got into this thread and decided I would locate and adjust my air governor. Now where to find it? Tried multiple compartments only to see the air lines dive into a giant bundle of black wires and tubes. Finally opened the engine bay and low and behold mounted on the block of my ISL400 just to the right and in plain view was my D2 air governor. "Oh, so that's what that is!" Off came the cap, loosened the 7/16 jam nut, turned it 1/4 turn counter clockwise and checked the dash. Perfect 125-130psi. Thank you all for the information and motivation. Now instead of dreading checking my front tires I'm looking forward to it!
Title: Re: D2 Governor
Post by: Pamela & Mike on February 24, 2021, 05:33:33 am
Post by: Pamela & Mike on February 24, 2021, 05:33:33 am
Where is the D2 located on my coach.
It will be close to the air compressor or even on the compressor in some cases. Some are mounted on the frame rail around the area of the A/C compressor. I know this isn't an exact location but just where you need to look. It seems like depending on what shift installed the D2 would dictate the location.
Mike
Title: Re: D2 Governor
Post by: Big Al on February 24, 2021, 09:23:57 am
Post by: Big Al on February 24, 2021, 09:23:57 am
When you get your spare D2, also get the fittings and pre assemble. That way if you ever need to change the D2 on the road you just have attach the air lines and not mess with fittings.
Title: Re: D2 Governor
Post by: turbojack on February 24, 2021, 12:21:11 pm
Post by: turbojack on February 24, 2021, 12:21:11 pm
On my 2014 IH45 it is mounted to the side of the engine block.
Title: Re: D2 Governor
Post by: Spiderhitch on February 24, 2021, 08:20:21 pm
Post by: Spiderhitch on February 24, 2021, 08:20:21 pm
Found it. I will try to adjust air pressure up tomorrow. Will get spare for parts bin.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 24, 2021, 08:26:15 pm
Post by: Chuck & Jeannie on February 24, 2021, 08:26:15 pm
I will try to adjust air pressure up tomorrow.
Title: Re: D2 Governor
Post by: Phranko on February 24, 2021, 10:37:04 pm
Post by: Phranko on February 24, 2021, 10:37:04 pm
This thread reminded that the guy who does our chassis/engine maintenance told me it's a good
idea to "swap out that D2 at next service, keep the old one in the spares bin onboard".
Also a new drier is also in order since we can't read the date of the last upgrade, could be 2014 or 2016, just not sure.
I agreed with him and he'll have the parts on hand, ready to install.
A lesson learned from Bill Chaplin when I asked what tools he carried, "never the right one".
Bookmarked this thread just in case!
One more thing not to worry about while "sailing the asphalt highways".
idea to "swap out that D2 at next service, keep the old one in the spares bin onboard".
Also a new drier is also in order since we can't read the date of the last upgrade, could be 2014 or 2016, just not sure.
I agreed with him and he'll have the parts on hand, ready to install.
A lesson learned from Bill Chaplin when I asked what tools he carried, "never the right one".
Bookmarked this thread just in case!
One more thing not to worry about while "sailing the asphalt highways".
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 24, 2021, 11:00:09 pm
Post by: Chuck & Jeannie on February 24, 2021, 11:00:09 pm
...the guy who does our chassis/engine maintenance told me it's a good idea to "swap out that D2 at next service, keep the old one in the spares bin onboard".
https://www.napaonline.com/en/p/TWRBENOR275491X?partTypeName=Brake+Governor&impressionRank=4&keywordInput=governors
Title: Re: D2 Governor
Post by: CRY42 on February 25, 2021, 07:36:55 am
Post by: CRY42 on February 25, 2021, 07:36:55 am
After reading the D2 Governor post, thought I would take the Forum advice and purchase a spare.
But I see all different Part Numbers ? Is a D2 Governor the same, regardless of the Part Number ?
Thanks as always for the Forum and your kind advice.
But I see all different Part Numbers ? Is a D2 Governor the same, regardless of the Part Number ?
Thanks as always for the Forum and your kind advice.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 25, 2021, 08:31:23 am
Post by: Chuck & Jeannie on February 25, 2021, 08:31:23 am
Is a D2 Governor the same, regardless of the Part Number ?
First, you should try to find a genuine Bendix brand unit if possible. You will see a lot of generic knock-off reproductions, especially if you shop online at Amazon or eBay. The ad will say their product "...replaces Bendix D2..." or "Bendix style". These look-alike brands will probably work fine and do the job, but the genuine Bendix brand usually doesn't cost much more.
https://www.napaonline.com/en/p/TWRBENOR275491X?partTypeName=Brake+Governor&impressionRank=4&keywordInput=governors
Second, you will see different D2 governor part numbers with different pressure ratings. Some say "100-120", others say "105-125". Don't worry about the advertised pressure - they are usually adjustable after you get them installed. If the pressure is not what you want, you can change it.
Note: When you adjust the "set" pressure on the D2 you are raising or lowering both the cut-in and cut-out pressure. The range between the two pressures is supposed to remain constant at about 20 psi (although I have had some where it seems to be more like 30 psi).
NAPA stores are pretty easy to find, and a good place to get the genuine Bendix D2.
Title: Re: D2 Governor
Post by: CRY42 on February 25, 2021, 08:41:22 am
Post by: CRY42 on February 25, 2021, 08:41:22 am
Thank you, Chuck !
The Forum is the GREATEST.
Have a great day.
The Forum is the GREATEST.
Have a great day.
Title: Re: D2 Governor
Post by: Phranko on February 25, 2021, 07:05:45 pm
Post by: Phranko on February 25, 2021, 07:05:45 pm
Quote
I can see no good reason to keep a "used" D2 for a spare, when brand new fresh ones are so inexpensive.
After thinking about it, I agree.
I carry 2 new ones (came with the coach), so why carry around a used one.
DUH!
Title: Re: D2 Governor
Post by: Woody & Sitka on February 25, 2021, 11:34:34 pm
Post by: Woody & Sitka on February 25, 2021, 11:34:34 pm
I'm a life long gear-head, but am embarrassed to admit that I don't know where the air compressor or D2 is on my coach, since my Foretravel Owners Manual is severely lacking in the gear-head department and this thread assumes a lot. I've been unable to glean said detail from the forum or interwebs.
Could someone pleeze crawl under their ISM450 powered rig and take a picture of the D2 on their engine and post it here???...one that shows exactly where the D2 is, and what it looks like mounted on the ISM450? Thanks in advance. Woody.
Could someone pleeze crawl under their ISM450 powered rig and take a picture of the D2 on their engine and post it here???...one that shows exactly where the D2 is, and what it looks like mounted on the ISM450? Thanks in advance. Woody.
Where is the D2 located on my coach. My brake gauges show 100# on dash. Just replaced 2 leaking tank drains, 2 safety valves and check valves.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 26, 2021, 09:13:53 am
Post by: Chuck & Jeannie on February 26, 2021, 09:13:53 am
I don't know where the air compressor or D2 is on my coach...
BUT, I do have Google search! Google knows all.
There is a good chance that the D2 on your ISM450 is bolted directly to the engine air compressor. The photos below are of a ISM500 but should be the same general configuration as your engine. You can clearly see the D2 bolted to the air compressor, which is bolted to the engine, down low on the passenger side of the block.
If your D2 is not bolted directly to the air compressor, then it is probably close to this same location, perhaps bolted to the frame and connected to the air compressor with a short air hose. There will also be two additional air hoses connected to the D2 - one going to the wet tank. and the other going to the air dryer.
Title: Re: D2 Governor
Post by: John Duld on February 26, 2021, 11:38:24 am
Post by: John Duld on February 26, 2021, 11:38:24 am
I'm on the other side of the coin on new or used (working) spare.
If I need it it will get me home. If I install a new spare that should work but if it doesn't then what?
I have been burned by new stuff that didn't work in the past.
If I need it it will get me home. If I install a new spare that should work but if it doesn't then what?
I have been burned by new stuff that didn't work in the past.
Title: Re: D2 Governor
Post by: dsd on February 26, 2021, 11:46:34 am
Post by: dsd on February 26, 2021, 11:46:34 am
Could someone pleeze crawl under their ISM450 powered rig and take a picture of the D2 on their engine and post it here???...one that shows exactly where the D2 is, and what it looks like mounted on the ISM450? Thanks in advance. Woody.
Scott
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 26, 2021, 11:50:48 am
Post by: Chuck & Jeannie on February 26, 2021, 11:50:48 am
Scott,
Hard to tell from your photo. Is your D2 mounted on the frame or directly on the engine air compressor?
Hard to tell from your photo. Is your D2 mounted on the frame or directly on the engine air compressor?
Title: Re: D2 Governor
Post by: Chuck & Jeannie on February 26, 2021, 11:55:31 am
Post by: Chuck & Jeannie on February 26, 2021, 11:55:31 am
I'm on the other side of the coin on new or used (working) spare.
My reasoning is that if you remove a D2 because it is not working, then why would you assume it would work if it was later reinstalled?
Of course, I generally carry 2 or 3 brand new D2s in my parts drawer. If the first one don't work, I'll pull out another one.
In past years I've also given a couple of them away to other coach owners who were in a bind. Kinda like a party favor.
Title: Re: D2 Governor
Post by: dsd on February 26, 2021, 04:47:28 pm
Post by: dsd on February 26, 2021, 04:47:28 pm
Scott,
Hard to tell from your photo. Is your D2 mounted on the frame or directly on the engine air compressor?
Title: Re: D2 Governor
Post by: John Duld on February 28, 2021, 12:47:55 pm
Post by: John Duld on February 28, 2021, 12:47:55 pm
Chuck I did say a working spare.
Some here will replace a working governor just because they want a new one. That working takeoff would serve as an on the side of the road replacement for me.
Some here will replace a working governor just because they want a new one. That working takeoff would serve as an on the side of the road replacement for me.
Title: Re: D2 Governor
Post by: Peter on June 16, 2021, 11:09:29 am
Post by: Peter on June 16, 2021, 11:09:29 am
Where is the wet tank that has been stated in this topic that requires letting air out? And can all of this be done without safety stands, just at the back or eh engine?
Title: Re: D2 Governor
Post by: oldguy on June 16, 2021, 11:19:11 am
Post by: oldguy on June 16, 2021, 11:19:11 am
There is a air line on the drivers side in front of the rear tire with a valve on it
that drains the wet tank.
that drains the wet tank.
Title: Re: D2 Governor
Post by: wolfe10 on June 16, 2021, 11:20:19 am
Post by: wolfe10 on June 16, 2021, 11:20:19 am
Again, you should NEVER get anything but clean dry air from the wet tank drain valve. If you do, the air dryer has FAILED.
Title: Re: D2 Governor
Post by: Peter on June 16, 2021, 11:28:16 am
Post by: Peter on June 16, 2021, 11:28:16 am
Thanks again guys for the location of the valve. The coach can be off and NOT on safety stands for all of this right. I do have the coach tires blocked
Title: Re: D2 Governor
Post by: wolfe10 on June 16, 2021, 11:32:49 am
Post by: wolfe10 on June 16, 2021, 11:32:49 am
Thanks again guys for the location of the valve. The coach can be off and NOT on safety stands for all of this right. I do have the coach tires blocked
No need to safety stands. You can reach in to access the valve without getting under the coach. Just kneel down in front of the driver's side rear tire and look up/forward.
Title: Re: D2 Governor
Post by: craneman on June 16, 2021, 12:15:19 pm
Post by: craneman on June 16, 2021, 12:15:19 pm
On this coach it is on the passenger side behind the A/C compressor.
Title: Re: D2 Governor
Post by: Doug W. on June 16, 2021, 12:32:49 pm
Post by: Doug W. on June 16, 2021, 12:32:49 pm
On this coach it is on the passenger side behind the A/C compressor.
...wet tank drain valve?
Title: Re: D2 Governor
Post by: wolfe10 on June 16, 2021, 12:33:18 pm
Post by: wolfe10 on June 16, 2021, 12:33:18 pm
On this coach it is on the passenger side behind the A/C compressor.
Wow, never seen the wet tank drain there. Wonder if someone rerouted it.
OK, on edit, think Craneman is referring to the common location of the air governor/D2.
Title: Re: D2 Governor
Post by: craneman on June 16, 2021, 01:11:38 pm
Post by: craneman on June 16, 2021, 01:11:38 pm
Yes I was following the top of the thread and missed moving it to drain valve.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on June 16, 2021, 03:46:54 pm
Post by: Chuck & Jeannie on June 16, 2021, 03:46:54 pm
Yes I was following the top of the thread and missed moving it to drain valve.
Title: Re: D2 Governor
Post by: Peter on July 11, 2021, 12:44:36 pm
Post by: Peter on July 11, 2021, 12:44:36 pm
I decided to adjust my d2 governor so I could get the pressure up around 125 before to it releases pressure. ( it was at about 110-115) When I adjust it counterclockwise gently to increase the pressure it then released at at about 140. When I rotated it clockwise to decrease the pressure I had to do almost a 3/4 turn to get it down and then it went to about 110. I fiddled some more with it and the only two settings I can get it hold are 140 and about 110. Is it Alright to leave it at 140?? If I can not get it set again to 125 does this mean the unit has to be replaced. ? Maybe the adjustment is really sensitive. Any one had these experiences? Perhaps I should have just left the darn thing alone!!
Title: Re: D2 Governor
Post by: Protech Racing on July 11, 2021, 12:50:14 pm
Post by: Protech Racing on July 11, 2021, 12:50:14 pm
125seems optimal. 140 may find more leaks. Try turning a 1/4 turn and cycling the system .
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 27, 2021, 12:44:40 pm
Post by: Journey, Roam, Explore on October 27, 2021, 12:44:40 pm
Since a few months ago when I replaced my air dryer my PSI is steadily been increasing. Now today leaving Sioux falls going south I noticed that my gauges are topping off at 150 psi. I'm not really hearing it release Air anymore. It's cold outside it's raining and I have another 180 miles to go before I get to where I'm headed. At idle both PSI gauges are running at around:110, but at highway speeds they're headed they're topping at 150 psi. I drained my wet tank which I haven't done in a little while and got some water mixed with some rust out and then just clear air. Anybody have this happen to them before I guess I need to change the D2 out? Unfortunately I won't be able to do it for a few days. Any input would be appreciated...
Bob
Bob
Title: Re: D2 Governor
Post by: craneman on October 27, 2021, 01:13:16 pm
Post by: craneman on October 27, 2021, 01:13:16 pm
Many new ones come set at 130 which I set mine. Makes airing up front tires easier for me. The adjustment is very sensitive.
Title: Re: D2 Governor
Post by: Elliott on October 27, 2021, 01:21:36 pm
Post by: Elliott on October 27, 2021, 01:21:36 pm
FYI the remanned haldex units use plugs that require a 3/16 allen wrench. That size key isn't always included in the little sets you can buy so double check you have one before you head to the store.
I spent more time setting up the new governor (which can be done inside where it's warm) than actually taking it off and putting it back on.
I spent more time setting up the new governor (which can be done inside where it's warm) than actually taking it off and putting it back on.
Title: Re: D2 Governor
Post by: craneman on October 27, 2021, 01:50:09 pm
Post by: craneman on October 27, 2021, 01:50:09 pm
I keep a spare with the plugs already installed in the correct ports. Makes the change quick.
Title: Re: D2 Governor
Post by: Jeff & Sandy on October 27, 2021, 02:22:25 pm
Post by: Jeff & Sandy on October 27, 2021, 02:22:25 pm
Since a few months ago when I replaced my air dryer my PSI is steadily been increasing. Now today leaving Sioux falls going south I noticed that my gauges are topping off at 150 psi. I'm not really hearing it release Air anymore. It's cold outside it's raining and I have another 180 miles to go before I get to where I'm headed. At idle both PSI gauges are running at around:15 but at highway speeds they're headed they're topping at 150 psi. I drained my wet tank which I haven't done in a little while and got some water mixed with some rust out and then just clear air. Anybody have this happen to them before I guess I need to change the D2 out? Unfortunately I won't be able to do it for a few days. Any input would be appreciated...
Bob
If water and rust came out you may have an air dryer issue. Only air is supposed to come out of that valve.
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 27, 2021, 02:32:35 pm
Post by: Journey, Roam, Explore on October 27, 2021, 02:32:35 pm
Yeah I haven't been draining it very often. It was just slightly rust colored water. Since it's raining in the ground as wet it's a little hard to tell. The air dryer is new from find it parts and even though it wasn't the exact same replacement and I should have kept my core but I didn't.
I'm not hearing the purge valve go off and the purge valve is on the air dryer is it not? I thought maybe I had blocked something up when I turned around in Wyoming cuz that's when I started seeing increased pressures but not like this. Right now at idle I'm getting 115PSI. I went out and looked at the D2 and the dial was very loose so I turned it a little left and that Max the PSI at 150 so I went back out and turned it to the right and it only went a little bit. I'm at a rest stop right now so I'm going to try driving a little bit more and see if it changed anything. I'm starting to think that I may have an actual spare somewhere I know I have a Bendix spare but I don't remember if it's the D2 or not. Got 127 miles left for the day so I'm going to try to make it there and then look into replacing this
I'm not hearing the purge valve go off and the purge valve is on the air dryer is it not? I thought maybe I had blocked something up when I turned around in Wyoming cuz that's when I started seeing increased pressures but not like this. Right now at idle I'm getting 115PSI. I went out and looked at the D2 and the dial was very loose so I turned it a little left and that Max the PSI at 150 so I went back out and turned it to the right and it only went a little bit. I'm at a rest stop right now so I'm going to try driving a little bit more and see if it changed anything. I'm starting to think that I may have an actual spare somewhere I know I have a Bendix spare but I don't remember if it's the D2 or not. Got 127 miles left for the day so I'm going to try to make it there and then look into replacing this
Title: Re: D2 Governor
Post by: Chuck & Jeannie on October 27, 2021, 02:46:36 pm
Post by: Chuck & Jeannie on October 27, 2021, 02:46:36 pm
If your air gauges are reading 150 psi and this is the actual pressure in your brake tanks (IE the gauges are not malfunctioning) then you definitely have a problem. If you don't hear the air dryer purging (when the air compressor cuts out) then your D2 may be stuck and has lost control over the air compressor. In this case the only thing left that controls the system air pressure is the pressure relief safety valve on your wet tank. This valve should open at about 150 psi if it is operating correctly. If run uncontrolled, the air compressor will continue to produce pressure and the excess pressure will (hopefully) be vented through the relief valve. This is not a safe way to continue operating the coach. You should replace the D2 governor at the first opportunity.
Note: There is also a pressure relief safety valve on your air dryer, but it probably does not open until 175 psi. See link below:
Haldex KN31527 Safety Valve, 3/8" NPT, 175 PSI: AnythingTruck.com, Truck &... (https://www.anythingtruck.com/product/070-KN31527.html)
D2 adjustment instructions here:
Note: There is also a pressure relief safety valve on your air dryer, but it probably does not open until 175 psi. See link below:
Haldex KN31527 Safety Valve, 3/8" NPT, 175 PSI: AnythingTruck.com, Truck &... (https://www.anythingtruck.com/product/070-KN31527.html)
D2 adjustment instructions here:
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 27, 2021, 07:02:43 pm
Post by: Journey, Roam, Explore on October 27, 2021, 07:02:43 pm
Thanks chuck. That's what I needed to know. Fortunately about a year ago somebody was talking about this very part and I ordered one forgot what exactly I ordered but I knew I had a box with Bendix on it. So I now have that in my hand and I guess tomorrow morning before I get on the road I'll be changing it out.
Any tips on it would be appreciated. I guess I don't know how this was factory adjusted until I install it and see what happens.
Any tips on it would be appreciated. I guess I don't know how this was factory adjusted until I install it and see what happens.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on October 27, 2021, 08:52:52 pm
Post by: Chuck & Jeannie on October 27, 2021, 08:52:52 pm
I guess I don't know how this was factory adjusted until I install it and see what happens.
Make a note of any air line connections before you remove them. Put the included set screw plugs in the unused ports so it looks just like the old one that you take off. Any other questions refer to the tech sheet I linked in prior post.
Title: Re: D2 Governor
Post by: AC7880 on October 27, 2021, 10:20:53 pm
Post by: AC7880 on October 27, 2021, 10:20:53 pm
Thanks chuck. That's what I needed to know. Fortunately about a year ago somebody was talking about this very part and I ordered one forgot what exactly I ordered but I knew I had a box with Bendix on it. So I now have that in my hand and I guess tomorrow morning before I get on the road I'll be changing it out.
Any tips on it would be appreciated. I guess I don't know how this was factory adjusted until I install it and see what happens.
Changing D2 - access method (https://www.foreforums.com/index.php?topic=43383.msg436463#msg436463)
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 30, 2021, 11:30:03 am
Post by: Journey, Roam, Explore on October 30, 2021, 11:30:03 am
Well I changed it out the day before up in Nebraska and initially at idle and at 1500 RPMs while not moving the PS I stayed at 1:30 or below. But once I got on the road yesterday that quickly changed and I was hovering between 130 and 150 psi again. finally I stopped and got out and cranked the wet tank open partially. What came out was water mixed with a white chalky substance so I'm pretty sure that my air dryer is kaput. I left the wet tank ranked and drove on down the road and I was able to keep the pressure is down around 130 PSI. Although there were times again when it would go up to 150. The air dryer was remanufactured haldex from find it parts that I installed last year in Arizona. So not even a year old. I've got a rebuild kit coming to Mark's house in Uvalde and I'll have in a couple days but today I am out for the parts to do the bypass. I think that when I was in Wyoming and dispersed camping and I made a u-turn that I may have jammed that end of the coach where the air dryer is into some dirt and that clogged up my purge valve. I'm not sure if that would be connected with this or not. I guess there's a possibility that my governor was bad but I don't think that was the issue. If anybody has any other ideas I'd be happy to hear them. The biggest question is whether it's the actual compressor but my understanding is that the governor should control that. I have a new governor on order as well just in case.
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 30, 2021, 11:32:03 am
Post by: Journey, Roam, Explore on October 30, 2021, 11:32:03 am
And it's a pain in the butt because I'm also having air pressure issues with my Jeep Grand Cherokee that has air suspension on it. I've got a leak in one of the connectors for the front shock and while I thought I had a spare connector I can't find it. I've got Parts on order but they won't get here until Monday night and the Jeep needs to go to the dealership to get the nitrogen tank refilled. I've got an appointment Monday but now the parts aren't due to come in until Monday night so I'm going to have to change it to Tuesday. Otherwise used Mopar Parts which are going to be three times more expensive at least. I'm just hoping they don't tell me that I need to change out the air compressor because that would be a very expensive job.
Title: Re: D2 Governor
Post by: craneman on October 30, 2021, 11:36:13 am
Post by: craneman on October 30, 2021, 11:36:13 am
Well I changed it out the day before up in Nebraska and initially at idle and at 1500 RPMs while not moving the PS I stayed at 1:30 or below. But once I got on the road yesterday that quickly changed and I was hovering between 130 and 150 psi again. finally I stopped and got out and cranked the wet tank open partially. What came out was water mixed with a white chalky substance so I'm pretty sure that my air dryer is kaput. I left the wet tank ranked and drove on down the road and I was able to keep the pressure is down around 130 PSI. Although there were times again when it would go up to 150. The air dryer was remanufactured haldex from find it parts that I installed last year in Arizona. So not even a year old. I've got a rebuild kit coming to Mark's house in Uvalde and I'll have in a couple days but today I am out for the parts to do the bypass. I think that when I was in Wyoming and dispersed camping and I made a u-turn that I may have jammed that end of the coach where the air dryer is into some dirt and that clogged up my purge valve. I'm not sure if that would be connected with this or not. I guess there's a possibility that my governor was bad but I don't think that was the issue. If anybody has any other ideas I'd be happy to hear them. The biggest question is whether it's the actual compressor but my understanding is that the governor should control that. I have a new governor on order as well just in case.
Title: Re: D2 Governor
Post by: Chuck & Jeannie on October 30, 2021, 11:56:57 am
Post by: Chuck & Jeannie on October 30, 2021, 11:56:57 am
I stopped and got out and cranked the wet tank open partially. What came out was water mixed with a white chalky substance so I'm pretty sure that my air dryer is kaput.
But, even with the D2 governor and the air compressor working correctly, if the air dryer is plugged up inside (due to junk from failed cartridge) then your "high air pressure" problem may still remain.
If you see "water mixed with white substance" your air dryer is most certainly kaput. Fix it when you get the rebuild kit, then see how your air system responds. Pretty sure will make things right.
Highly unlikely you would need a new air compressor. 8)
Title: Re: D2 Governor
Post by: Journey, Roam, Explore on October 30, 2021, 01:12:05 pm
Post by: Journey, Roam, Explore on October 30, 2021, 01:12:05 pm
Yeah I agree I'll try the corrosion x idea of craneman when I install the bypass tomorrow. I'll rebuild my air dryer in Uvalde when I get there. I don't think it's the compressor either but twig mentioned it and that scared the heck out of me cuz I know that would be a much pricier fix. I'll let you know. ;D
Title: Re: D2 Governor
Post by: craneman on October 30, 2021, 02:13:15 pm
Post by: craneman on October 30, 2021, 02:13:15 pm
The unloader valves are upstream of the dryer. When working the governor pressurizes the unloader and it tells the compressor to stop making air. I
https://www.youtube.com/watch?v=ZYMsiQFsNUQ
https://www.youtube.com/watch?v=ZYMsiQFsNUQ