Jcb 3cx 1989ish problems

[dkenny]

Hi all

new to the forum

a family friend has an old 3cx at his property that has not moved for a while that he wants rid of but it has a few issues and he has no idea how to operate it!

i have managed to get it started and move the buckets but i cannot get it to move!

the switch on the steering column has been cannibalised and there is a 2 way toggle switch that i believe now selects forward or reverse however it just will jot move

i think it almost tried to move but no good

iv checked what i believe to be teansmission oil and it appears to be on the lower mark…this may be a good place to start perhaps…so can anyone recommend what oil should be in there and also where the correct place to fill is!

thanks in advance for any pointers…from a complete novice 3cx operator

cheers

 

[Henery]

Transmission needs ATF, is the main stick in a gear ? …… start with the simplest things.
If there’s oil on the stick it should drive.

 

[Netherfield]

Handbrake pads could be seized by rust to the brake disc.

 

[dkenny]

Where does the atf actually go in?

i think i had it in first

does it matter where ignition switch is? Iv been looking on youtube and seen that this could be a problem

had to initially start it byshorting starter motor out

 

[agrimax]

The key switch will need to be turned on,ie ignition on, to provide power to the relays which in turn power the f/r solenoids. Nearly sure the relays are behind the left hand side of the dash and you should hear them click as you move the f/r switch. The solenoids are on top of the transmission just behind the torque converter housing. It'll have a Synchroshuttle transmission which needs the oil level checked with the engine off. Presumably you've found the long dipstick under the small hinged bonnet on the left side? The ATF is filled through the dipstick tube. It should move f or r in 1st gear irrespective if the park brake pads or caliper is seized or not. If still no movement,you'll need to check for power at those solenoids on top of the box...bearing in mind that the torque converter oil pump or clutch pack plates could be knackered too.

 

[ACEngineering]

Where does the atf actually go in?

i think i had it in first

does it matter where ignition switch is? Iv been looking on youtube and seen that this could be a problem

had to initially start it byshorting starter motor out

The key switch will need to be turned on,ie ignition on, to provide power to the relays which in turn power the f/r solenoids. Nearly sure the relays are behind the left hand side of the dash and you should hear them click as you move the f/r switch. The solenoids are on top of the transmission just behind the torque converter housing. It'll have a Synchroshuttle transmission which needs the oil level checked with the engine off. Presumably you've found the long dipstick under the small hinged bonnet on the left side? The ATF is filled through the dipstick tube. It should move f or r in 1st gear irrespective if the park brake pads or caliper is seized or not. If still no movement,you'll need to check for power at those solenoids on top of the box...bearing in mind that the torque converter oil pump or clutch pack plates could be knackered too.

Transmission oil fills via the dipstick tube.
To check you run machine for couple minutes then stop it and check level within 30 to 60 seconds of stopping.
If you check it after it's been stopped a while oil will have drained back to the box and will appear higher on the stick but is in effect low. It's much the same check for most JCB'S but other torque converter transmissions do vary.

 

[ACEngineering]

Hi all

new to the forum

a family friend has an old 3cx at his property that has not moved for a while that he wants rid of but it has a few issues and he has no idea how to operate it!

i have managed to get it started and move the buckets but i cannot get it to move!

the switch on the steering column has been cannibalised and there is a 2 way toggle switch that i believe now selects forward or reverse however it just will jot move

i think it almost tried to move but no good

iv checked what i believe to be teansmission oil and it appears to be on the lower mark…this may be a good place to start perhaps…so can anyone recommend what oil should be in there and also where the correct place to fill is!

thanks in advance for any pointers…from a complete novice 3cx operator

cheers

Might have a handbrake drive disconnect switch too that could be failed.

 

[Netherfield]

Might have a handbrake drive disconnect switch too that could be failed.

I had one of the era 1990 H reg, no disconnect switch on the handbrake, which was a pity because mine had been driven with the handbrake on and glazed the pads, so no longer worked until I replaced the pads.

 

[ACEngineering]

I had one of the era 1990 H reg, no disconnect switch on the handbrake, which was a pity because mine had been driven with the handbrake on and glazed the pads, so no longer worked until I replaced the pads.

not sure when it came in, landlord 1989 one has a buzzer and red light on the dash i think rather than disconnect the drive? at some point they would have twigged they can disconnect the drive though.

 

[JWL]

Definitely no handbrake disconnect drive switch, we had a new 3CX come to the farm I worked on where they kept one that was subbed out most of the year.
The driver, a very experienced operator got in it on the first day and went off to a job about 30 miles away and got a couple of miles up the road before he clocked that the handbrake was still on. That would have been an embarrassing call he had to make to the boss and hard to claim on warranty

 

[dkenny]

Im going back to it later on

il be armed with some atf so hopefully that sorts it

next thing is the brakes…there is no pressure under foot

also the pedal on the right is clearly the accelerator…what is the pedal on the left?

cheers

 

[dkenny]

 

[dkenny]

Thats a picture of her so it may help some of you help me!

 

[agrimax]

The pedal on the left is a transmission disconnect or dump valve. It's really only meant to be used for changing gear like a clutch but do not allow it to slip... If it still works at all...
Check if there is oil in the brake reservoirs behind the top of the dashboard. Only use mineral fluid such as LHM or 10w hydraulic. Probably needs bled at the bleeders on the axle brake housings but if DOT 3/4 brake fluid has been used before, the seals etc will be like jelly....

 

[dkenny]

There was no resistance on this pedal so if its a dump valve for the hydro fluid id of expected something to be there to offer eesistance but its as floppy as the brake pedals

The pedal on the left is a transmission disconnect or dump valve. It's really only meant to be used for changing gear like a clutch but do not allow it to slip... If it still works at all...
Check if there is oil in the brake reservoirs behind the top of the dashboard. Only use mineral fluid such as LHM or 10w hydraulic. Probably needs bled at the bleeders on the axle brake housings but if DOT 3/4 brake fluid has been used before, the seals etc will be like jelly....

 

[ACEngineering]

There was no resistance on this pedal so if its a dump valve for the hydro fluid id of expected something to be there to offer eesistance but its as floppy as the brake pedals

The dump pedal wont have any great feel to it at all. It's only working an electric switch or on very old ones a cable.

 

[Nitrams]

Transmission oil fills via the dipstick tube.
To check you run machine for couple minutes then stop it and check level within 30 to 60 seconds of stopping.
If you check it after it's been stopped a while oil will have drained back to the box and will appear higher on the stick but is in effect low. It's much the same check for most JCB'S but other torque converter transmissions do vary.

Hope you don’t mind me butting in. I have a similar lack of drive in f/r with a 1990 3cx. Can you advise where the test ports are to pressure test the packs. There is small blanking plugs just behind and below the f/r solenoid. Would these be the test ports. I take it there is just a forward and reverse pack. The shuttle is powering 12v to the fwd rev solenoids so not electrical

 

[agrimax]

Yes those are the test ports for the packs. From memory, I think the pressure should be around 150 psi but no more than that.
Have you checked the suction filter is clean and replaced the spin on filter? It would be less common for both packs to be worn or leaking at the same time and more likely to be a weak TC and/or a worn transmission pump giving rise to lack of drive in both directions.

 

[Nitrams]

Yes those are the test ports for the packs. From memory, I think the pressure should be around 150 psi but no more than that.
Have you checked the suction filter is clean and replaced the spin on filter? It would be less common for both packs to be worn or leaking at the same time and more likely to be a weak TC and/or a worn transmission pump giving rise to lack of drive in both directions.

I did think it’s likely to be the pump or something internal but wanted to pressure test first. Yes we have done the spin on filter not long ago.I havnt done the suction filter, where is this pls?

 

[ACEngineering]

I did think it’s likely to be the pump or something internal but wanted to pressure test first. Yes we have done the spin on filter not long ago.I havnt done the suction filter, where is this pls?

oval plate at bottom of transmission, will need a new cork gasket. tbh if its blocked then theres something wrong internally anyway. pressure 150 to 165psi would be ideal or around 140psi at idle. anything below 100psi will be giving you problems. The end result is the same though box out strip replace all seals, clutch packs, update plastic pistons and thrust washers, new transmision pump and recon converter.