Jcb 3cx sitemaster 4x4 transmission problem

[reas]

HI

New to this forum, not sure if I should enter here forgive me if not, I have a Jcb 3cx 4x4 1989, i was using it, parked it up, started it the following day and it wont move forward or reverse, engine is good both solenoids for forward and reverse work, vant understand why it wont move, the FWD/RVSRE selecter is working, inessence all electrics are good, before this it had plenty of push and could dig into a pile of stone with ease, could you please forward the link for the service manual.

Hope you can help.

Regards
Stu

[Stock]

What level of oil is in it??

sounds to me like the tranny pump has air locked.................

[ianoz]

Try the switch on the handbrake .Cuts the drive when on .May have stuck .

[d4c24a]

handbrake

highly unlikely to have a switch at that age

[ROCKHOUSEDIY]

1987 Transmission wont drive in any direction

highly unlikely to have a switch at that age

I have a similar problem .My 1987 3 CX worked fine the other day.When I started it the next day it would not move in any gear and also wouldnt work in forward or reverse I checked the shuttle solenoids and thy work fine I did notice a rattling noise in the in the torque converter which is noticable sometimes and would have to listen carefully more times to hear it.Is my problem in the torque converter im wondering is there a possible fault which can occur suddenly without any warning. Transmission oil and filters were changed just in case there was cavitation issues.

[Mick-the-fitter]

I have a similar problem .My 1987 3 CX worked fine the other day.When I started it the next day it would not move in any gear and also wouldnt work in forward or reverse I checked the shuttle solenoids and thy work fine I did notice a rattling noise in the in the torque converter which is noticable sometimes and would have to listen carefully more times to hear it.Is my problem in the torque converter im wondering is there a possible fault which can occur suddenly without any warning. Transmission oil and filters were changed just in case there was cavitation issues.

Could be torque converter! Or you could try the transmission oil or filter!

Mick

[Mick-the-fitter]

Could be torque converter! Or you could try the transmission oil or filter!

Mick

Another thought, it may be the switch which cuts the drive, on the manual gear lever on your right hand, if the button is stuck in it will permanently cut the drive!

Mick

[ROCKHOUSEDIY]

Another thought, it may be the switch which cuts the drive, on the manual gear lever on your right hand, if the button is stuck in it will permanently cut the drive!

Mick

I have verified power is going down to the solenoids . I can hear the solenoids clicking when the ignition is turned on with forward reverse lever selected .(engine is not running )

[Mick-the-fitter]

I have verified power is going down to the solenoids . I can hear the solenoids clicking when the ignition is turned on with forward reverse lever selected .(engine is not running )

Ok ok so we then may have a problem with the shuttle valve assembly which is actuated by the two solenoids, or a problem with the oil supply to the shuttle valve

Mick

[JCBWMB]

trans problem

Ok ok so we then may have a problem with the shuttle valve assembly which is actuated by the two solenoids, or a problem with the oil supply to the shuttle valve

Mick

Hi Mick,I have a 2009 3cx which sometimes won't change up to 5th an 6th gears.Also won't downshift on hills,but not always!
Had JCB Tech check with laptop and trans pressure gauges and all as per specs.Any thoughts??Would appreciate any ideas.

[AndrewMawson]

highly unlikely to have a switch at that age

My 1989 3CX had a switch on the handbrake. (Sold it now)

[v8druid]

My '86 black cab has a tranny disengage button on the front bucket control knob - it's a lil' ba****d for sticking in

[AndrewMawson]

Yes I seem to remember my Grey Cab had the same. Saved you embedding yourself too far in the pile

[X-Ray]

JCB Transmission

HI

New to this forum, not sure if I should enter here forgive me if not, I have a Jcb 3cx 4x4 1989, i was using it, parked it up, started it the following day and it wont move forward or reverse, engine is good both solenoids for forward and reverse work, vant understand why it wont move, the FWD/RVSRE selecter is working, inessence all electrics are good, before this it had plenty of push and could dig into a pile of stone with ease, could you please forward the link for the service manual.

Hope you can help.

Regards
Stu

Did you solve this problem? What was it? I have the same issue with a JCB 926/4 All terrain Forklift (same engine and trans). It's ok for about 10 mins from cold start then the trans seems to lock up and the machine won't move back or forward unless you give it loads of revs then it will lurch and drive as if the brakes are stuck on. The gearshift is then stuck in whatever gear it was in (4 gears on the stick) and it is not possible to pull the stick out of gear. The shuttle is working ok, it will do the high rev lurch back and forward. The gearbox by this time is really hot but nothing else is, If I keep trying to move it then the trans low pressure light comes on. I've changed the trans oil and filter, cleaned the screen in the g/box, drained the torque converter, filled with JCB 10W special trans oil. If I leave the machine for a few hours to cool down then it's ok again. The brakes are OK, The park brake is OK and the switch works OK. The foot disengage pedal works ok. Help Please Anyone.

[Stock]

Sounds like a warped clutch disc or two in the packs......................