Posts: 41
Threads: 17
Joined: Dec 2016
Hi fellow Gurus,
I have a problem with my gearbox or electrics possibly?
I jumped into the coach and fired up and went to put in gear, the pad was displaying SM (system malfunction) i have the 12 speed ZF. The coach goes into gear ok but when i try to pull away the revs hardly build and the coach judders but won't move off, as if the clutch isn't engaging.
I have had a local shop look into it and so far have had the gearbox sent away for inspection, it had a new ECU and valve block fitted, the clutch is in perfect order as well, everything has been refitted and the problem is still there, the coach is supplying air fine and the actuator has also been replaced. approx $7000 spent and no further forward!!
has anyone experienced these symptoms?
thanks
Rob
2008 NEWELL C-15 ZF 1218
Posts: 5,474
Threads: 258
Joined: Jul 2012
Don't know anything about ZF transmissions, but your comment doesn't build any revs is interesting. Check the interfaces between the engine and transmission. Why is the engine not revving? Will the engine rev in neutral?
Richard and Rhonda Entrekin
95 Newell, 390 Ex caretaker
99 Newell, 512 Ex caretaker
07 Prevost Marathon, 1025
Maverick Hybrid Toad
Inverness, FL (when we're home
)
Posts: 653
Threads: 67
Joined: Jun 2016
Is it possible to engage this transmission with the brakes locked up?
Guy & Sue Cobham
Sioux Falls, South Dakota
1984 Classic 40' #59
Posts: 4,194
Threads: 635
Joined: Jul 2012
Michael Day
1992 Newell 43.5' #281
NewellOwner.com
Posts: 41
Threads: 17
Joined: Dec 2016
(05-03-2018, 05:07 PM)Richard Wrote: Don't know anything about ZF transmissions, but your comment doesn't build any revs is interesting. Check the interfaces between the engine and transmission. Why is the engine not revving? Will the engine rev in neutral?
Yep the engine revs cleanly in neutral, its like something is holding it back electronically when in gear, the clutch just starts to engage then the revs drop and it disengages the clutch.
(05-03-2018, 08:38 PM)Fulltiming Wrote: Have you checked for an error code? https://www.scribd.com/doc/137329279/ZF-...rror-Codes
Hi Michael,
Yep the code is 78 which interestingly is not on the chart! however i have found something on the internet that talks about the screen filter on the actuator, (the actuator has been replaced) it also talks about a stuck clutch fork but again this has been removed inspected and replaced. im at a total loss!
cheers
Rob
2008 NEWELL C-15 ZF 1218
(This post was last modified: 05-04-2018, 01:32 AM by
rwg200.)
Posts: 41
Threads: 17
Joined: Dec 2016
(05-03-2018, 08:12 PM)Guy Wrote: Is it possible to engage this transmission with the brakes locked up?
The brakes are free as the coach rolls fine, in order to engage a gear the parking brake has to be off as well, so its not a problem with the brakes being locked on.
Thanks
Rob
2008 NEWELL C-15 ZF 1218
Posts: 231
Threads: 52
Joined: Apr 2017
Check throttle position sensor
I’ve had problems with that sensor in trucks
Georgeb
Coach 385
Toad Mini Cooper
Posts: 4,194
Threads: 635
Joined: Jul 2012
Do you hear any air leak at the transmission.
https://www.youtube.com/watch?v=vvsp_eNPxvo
Michael Day
1992 Newell 43.5' #281
NewellOwner.com
