BJ73 - push button 4x4

[Wayne BJ73]

Hi there

As a few are aware I have put in a 2H diesel into my BJ73 - I also used the push button (vacume) 4x4 selector. The old 3b engine had the manual floor leaver selector.

I am having trouble selecting 4x4.

What I know about the system is: it uses vacume from the rear of the alternator this is them switch by two soloniods - which activates the bellows mounted on the transferr box..

I have a clicking sound when I push the button on the dash at the two solonoids - is there some way of manually checking the vacume belows on the trasferr case.

Is there a way of alos checking its in 4x4 within the shed instead of driving it down to the creak to test - had to use the winch last time as very imbarasing when unable to get 4x4.

If I have no luck with this are you able to change the transferr case without changing the gearbox (or removing the gearbox).

I hope someone is able to help.

many thanks

Wayne

 

[Francesco_from_Italy]

Transfer case and gearbox are toghether, but you con change almost every piece of the t-case (except the shaft coming from the gearbox) without changing the gearbox.

I didn't understand wich gearbox you have on you BJ, but I guess is an H55F; you just have to find another H55F with electric 4x4 or maybe with manual 4x4 and put it on you car.

Sorry for my english, I hope you understood...

Francesco

 

[roscoFJ73]

Hi there

As a few are aware I have put in a 2H diesel into my BJ73 - I also used the push button (vacume) 4x4 selector. The old 3b engine had the manual floor leaver selector.

I am having trouble selecting 4x4.

What I know about the system is: it uses vacume from the rear of the alternator this is them switch by two soloniods - which activates the bellows mounted on the transferr box..

I have a clicking sound when I push the button on the dash at the two solonoids - is there some way of manually checking the vacume belows on the trasferr case.

Is there a way of alos checking its in 4x4 within the shed instead of driving it down to the creak to test - had to use the winch last time as very imbarasing when unable to get 4x4.

If I have no luck with this are you able to change the transferr case without changing the gearbox (or removing the gearbox).

I hope someone is able to help.

many thanks

Wayne

I have never tried this but you could probably remove the vaccum diaphragm housing from the transfer case and press the button.
If its working you should see something moving.

I would check to see if you have vaccum 1st.
Sometimes you get vac in one hose and not the other,so you can swap hoses and the button function is reversed.

I think there is a rubber diapragm inside which can leak also.

To change over to a manual t/case shift arrangement you would need the appropriate front housing plate off another manual t.case.
To fit it you would have to strip the t/case to fit the new one .
It can be done working under the vehicle.

To see if its in/out of 4x4 you would need to lift it off the ground and see if you can spin the front wheels. Remember to lock the hubs

 

[roscoFJ73]

Transfer case and gearbox are toghether, but you con change almost every piece of the t-case (except the shaft coming from the gearbox) without changing the gearbox.

I didn't understand wich gearbox you have on you BJ, but I guess is an H55F; you just have to find another H55F with electric 4x4 or maybe with manual 4x4 and put it on you car.

Sorry for my english, I hope you understood...

Francesco

Your english is fine,we posted at the same time

 

[Wayne BJ73]

Hi there

Hi there all

Many thanks for your responses:

I have a few more questions now, you have created more questions -

I do have vacume but how do I know its enough - with my finger over the end of the line the vacume is very pitterful (minimal).

Are the lines plumed any special way - one vacume line from pump to the two solonoids then in two lines to the acutator.

I would suspect it would take alot of vacume to operate this actuator, taking into consideration the manual effort (human) needed when changing it manually from 2 to 4x4.

Has anyone able to post a picture from the manual on how this is plumbed? - my manual has been leant to a friend whom has forgoten to return it.

All the best

Wayne

 

[crushers]

the vacumm is very light on the shifter fork.
when you think you have the front end locked then crawl under and turn the front driveshaft (hubs UNLOCKED), if it turns then you are still in 2 WD.
another test is to reverse the 2 vacumm lines and do the test again. you might have the lines reversed.
if you locat the front half of a manual t/case then you can just hook up the linkage and go from there. the internals are the same between the 2. might as well change out to a lower set of gears while it is apart though.
cheers

 

[Entaran]

I don't know if this will be any help, but we used to have an old mercedes (70-something ... 74 280E from memory) and on those beasts almost everything is vacuum operated. When we had issues with the Vac system, we pulled out our trusty speco vac gauge with 0.5 metre rubber hose into a BRASS t-piece with 1 metre rubber hose off ONE side. When we wanted to check vac, we took the line off we wanted to check, plumbed it into the t-piece, finished the circuit with the 1metre spare hose and read off the gauge.

Might help you tell, you can then check against service manual figures. Helped us fix central locking, auto problems and a couple of other things

 

[roscoFJ73]

Hi there all
I do have vacume but how do I know its enough - with my finger over the end of the line the vacume is very pitterful (minimal).

Are the lines plumed any special way - one vacume line from pump to the two solonoids then in two lines to the acutator.

Wayne

It sounds as if they are plumbed correctly as long as they are not reversed which reverses the button function

The manual says you need 53.3KPA of vaccum. It has to be constant on the vac gauge.

Check the hoses for splits and bad connectiions

 

[Technikev]

It sounds as if they are plumbed correctly as long as they are not reversed which reverses the button function

The manual says you need 53.3KPA of vaccum. It has to be constant on the vac gauge.

Check the hoses for splits and bad connectiions

I believe that's about 7.3 PSI for those of us who don't speak in Kilopascals. I had to look it up...

-Kevin

 

[Wayne BJ73]

Hi there

Hi there all

many thanks for the infomation - due to some issues at work I have been recalled and are working nightshifts for the next 6 nights (13hr shifts)

As for the vacume - I like the idea of trying it with the actuator of the gear box - and do the process of ellimination.

I have a funny feeling the problem is in either two areas 1. Lack of vacume. 2. hooked up incorectly. Is there a section within the workshop manual which shows the correct piping - is someone able to post a picture?

I have already checked the hoses for leaks and have just purchased new ones today while passing through Pt Augusta.

Also have just bought a 12ht engine (2H Factory Turbo) which needs a total rebuild (but heard it running) - it was to cheap to say no (havent told the missus yet)

Again many thanks for all the information - will give you all an update next week when I fly home.

All the best'

Wayne