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Topic: retarder quit (Read 836 times) previous topic - next topic

retarder quit

hi guys, hope I can describe well enough so I can try to fix the retarder.
everything was going great and the retarder was doing fine and I jinxed myself by saying to my wife, these retarders are great they work like this....you know the rest of the story on that. Anyway did some research and I unplugged the joystick connector behind the panel and cleaned off the contacts. should add that the red  light switch before the failure was functioning normally, after that it did not light up. Back to the story, after replugging the connector in the back I get a flash on the red light of the switch and it goes right off. Repeating that procedure gets the same result...same flash on the red light and out again.Thinking maybe there is a short in the joystick switch. any way to check that? are new ones available? Any other suggestions?

Thanks, Windwalker
98 U295 36'
92 Grand Villa 29' front engine gas-Sold
Motorcade 18100

Re: retarder quit

Reply #1 –
My retarder quit working a while back, same symptoms . Replaced the 12 volt relay switch, amongst all the other wiring on the left side wall ahead of the transmission touchpad, easy fix in my case.
Doug W.
96 36' U270 CSGI #4946
04 Toyota Tacoma 4x4
PNW

Re: retarder quit

Reply #2 –
Quote from: windwalker –
Thinking maybe there is a short in the joystick switch. any way to check that? are new ones available?

Wind,

Start with the relay as they are cheep.  To answer your question, Allison # 295-21372 for the joy stick.


Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: retarder quit

Reply #3 –
Great start guys,
One question, where is the relay, looks remarkably similar to the one in the bay underneath that controls the water pump.
Is it underneath the panel with the switches and the joystick.
In Pennsylvania now and have to go over the mountains and if I could just take the relay for the waterpump and use that temporarily that would be great.
98 U295 36'
92 Grand Villa 29' front engine gas-Sold
Motorcade 18100

Re: retarder quit

Reply #4 –
On our '97  320 the relay is hid just to the left of the steering column right above where your left foot rides. On some coaches I have seen them behind the removable carpeted kick panel in front of your left foot.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: retarder quit

Reply #5 –
Quote from: windwalker –
after replugging the connector in the back I get a flash on the red light of the switch and it goes right off. Repeating that procedure gets the same result...same flash on the red light and out again.Thinking maybe there is a short in the joystick switch. any way to check that? are new ones available? Any other suggestions?

Thanks, Windwalker
The retarder light is only on (retarder activated) when the switch is "on" and brakes applied AND above 10 mph.............
at least that is the way ours works......... light doesn't come on just because the switch is on.

Maybe I didn't understand what you're problem was before unplugging the joystick.

Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: retarder quit

Reply #6 –
Thanks for the reply's
Removed joystick from armrest and really filed down the contacts with a nail file emery board on the entire contact and that did the trick.
Very nice having the retarder over the mountains.
98 U295 36'
92 Grand Villa 29' front engine gas-Sold
Motorcade 18100

Re: retarder quit

Reply #7 –
Sorry for adding such an elementary question to this but I just purchased my bus and the retarder is new to me.  I have been nervous to use the retarder but attempted it yesterday and it did nothing but I am not sure if it was user error yet.  If I am understanding correctly, I flip the retarder switch (does not light up) and then use the joy stick over 10mph?

Thank you in advance for any pointers!
2000 U320 36'
Build #5705

Re: retarder quit

Reply #8 –
Quote from: Farrarkc –
Sorry for adding such an elementary question to this but I just purchased my bus and the retarder is new to me.  I have been nervous to use the retarder but attempted it yesterday and it did nothing but I am not sure if it was user error yet.  If I am understanding correctly, I flip the retarder switch (does not light up) and then use the joy stick over 10mph?

Thank you in advance for any pointers!
You will need to be over 10 mph with retarder switch to "on" and when you hit the brakes you will feel it kick in... if it does kick in and you dont feel it, no worries... your wife will inform you to not push the brakes so hard..lol.. she blamed me until I let her drive..

When driving down a hill you will need to pull the joystick back 2 clicks to feel it working and every time you let off the gas (headed down hill) it will kick on until you push the gas pedal.

I would highly suggest getting the VPMSpc and adding it to your coach.. simple... easy to see all the different parameters of the coach monitoring system for the engine and trans.. but it also will help with the Retarder temps.. which can get very hot.. without knowing it until you actually see it..

Re: retarder quit

Reply #9 –
Hi Farrakha
I just keep the retarder switch activated all the time. braking action with the foot pedal will activate the retarder (the light will come on), a little at first then more the harder you press on the brake. You should notice quite a difference in braking with the switch activated versus not activated. You can also use the retarder going down mountains with the joystick alone (no foot on the brake)
helps in keeping the speed down. I usually drive at 60 and when it gets up to 65 and there is more hill to go down I will use the retarder to get back to 60, only thing to keep an eye on is transmission temperature, from what I hear 240 is a little to high but I never saw it get much over 200 but I am east coast so the rockies would be a bit different. Also important to note the retarder will deactivate at 15 MPH or so, and if going down a mountain when you get to the speed you set on the cruise control.
98 U295 36'
92 Grand Villa 29' front engine gas-Sold
Motorcade 18100

Re: retarder quit

Reply #10 –
Quote from: windwalker –
Hi Farrakha
I just keep the retarder switch activated all the time. braking action with the foot pedal will activate the retarder (the light will come on), a little at first then more the harder you press on the brake. You should notice quite a difference in braking with the switch activated versus not activated. You can also use the retarder going down mountains with the joystick alone (no foot on the brake)
helps in keeping the speed down. I usually drive at 60 and when it gets up to 65 and there is more hill to go down I will use the retarder to get back to 60, only thing to keep an eye on is transmission temperature, from what I hear 240 is a little to high but I never saw it get much over 200 but I am east coast so the rockies would be a bit different. Also important to note the retarder will deactivate at 15 MPH or so, and if going down a mountain when you get to the speed you set on the cruise control.
You will find that the retarder temperature is way higher than transmission temp. Until I got the VPMSpc I was using the trans temp on down hill to regulate the retarder use. After getting the VPMSpc found out the retarder temp. was going way over 250 deg. with the trans temp around 200. I will change my Transynd and filters because I have no idea how hot the fluid got.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: retarder quit

Reply #11 –
I think I am correct. My 1996 equipment is not set up to accept the VPMSpc system. What alternatives are available (e.g., a temp sensor on the retarder discharge?) to me in my 1996?
Alan & Gerri Ortiz
1996 U295 36 ft.
"Rocinante"
Hartwell, Georgia
1999 Subaru Forester
Build No. 4957 Motorcader 17399

Re: retarder quit

Reply #12 –
300 deg is max temp for retarder for a short period according to Allison. My limit is 250. YMMV
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: retarder quit

Reply #13 –
Quote from: Alan & Gerri Ortiz –
I think I am correct. My 1996 equipment is not set up to accept the VPMSpc system. What alternatives are available (e.g., a temp sensor on the retarder discharge?) to me in my 1996?
Alan...look for the gray round data plug should have 6 pins if so its a J1708 protocol....I just installed BlueFire data plug with the free app from the app store. Have it running on my Ipad mini4

Works well

Hans

Hans & Marjet
1995 U300 "Ben" (#4719)
3176B Cat,4060HD,Jake
SKP#139131
Motorcade#17579
2006 Honda Element (towed)

Re: retarder quit

Reply #14 –
Alan, you really don't need the plug, just the pinouts.  On my 1993 Newell I just tapped into the wires to install my 1st VMSpc.  Silverleaf didn't have the correct plug available 10+ years ago.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: retarder quit

Reply #15 –
Alan,
If you have the older OBD II port you can purchase a OBD II to Deutsch 9-Pin Connector adapter. Then you can use the SilverLeaf or BlueFire to analyze your coach.
John M.

OBD II to Deutsch 9-Pin Connector

More options:
OBD II to Deutsch 9-Pin Connector - Google Search
John & Carm Morales

"We travel not to go anywhere, but to just go.  We travel for travel's sake.  Our great desire is to move."