Fuso Canter Transfer Case vacuum actuation

@OzWanderer I got mine working again. The solenoids were really crusty so needed replacing anyway, but the price from Mitsi for the solenoid pack was silly money. So I made my own using a £13 pattern solenoid pack for a Mitsi L200 and £10 of silicon vacuum line. It has 6.5mm blades that take a standard crimp terminal and I potted the plug receptor with sealant. That bodged bottle on yours is replacing a small tubular buffering 'tank' that has a rubber grommet (as a bellow) at each end, that I can only guess is a just a way of making the solenoids water-tight without restricting the piston movement. As each solenoid energises it displaces air out of it's case, and when de-energises it needs to suck it back in. For now, I've just using the breathing end caps that came with the new solenoids. If the actuator engages the transfer case in 2wd, simply swap over the vacuum hoses at the actuator. I've also mounted the solenoid pack next to the actuator instead of up in the chassis so that can keep an eye on it, and for quick replacement if need be. I may even carry one as a spare as they are small and cost peanuts.

1612209077689.png

1612211486750.png

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Probably not to most folk's standard, but here's what I've done...

1612209366057.png

1612209405697.png
 

kerry

Expedition Leader
@OzWanderer I got mine working again. The solenoids were really crusty so needed replacing anyway, but the price from Mitsi for the solenoid pack was silly money. So I made my own using a £13 pattern solenoid pack for a Mitsi L200 and £10 of silicon vacuum line. It has 6.5mm blades that take a standard crimp terminal and I potted the plug receptor with sealant. That bodged bottle on yours is replacing a small tubular buffering 'tank' that has a rubber grommet (as a bellow) at each end, that I can only guess is a just a way of making the solenoids water-tight without restricting the piston movement. As each solenoid energises it displaces air out of it's case, and when de-energises it needs to suck it back in. For now, I've just using the breathing end caps that came with the new solenoids. If the actuator engages the transfer case in 2wd, simply swap over the vacuum hoses at the actuator. I've also mounted the solenoid pack next to the actuator instead of up in the chassis so that can keep an eye on it, and for quick replacement if need be. I may even carry one as a spare as they are small and cost peanuts.

View attachment 639892

View attachment 639916

View attachment 639917
Probably not to most folk's standard, but here's what I've done...

View attachment 639894

View attachment 639895
love that ingenuity
 
@OzWanderer I got mine working again. The solenoids were really crusty so needed replacing anyway, but the price from Mitsi for the solenoid pack was silly money. So I made my own using a £13 pattern solenoid pack for a Mitsi L200 and £10 of silicon vacuum line. It has 6.5mm blades that take a standard crimp terminal and I potted the plug receptor with sealant. That bodged bottle on yours is replacing a small tubular buffering 'tank' that has a rubber grommet (as a bellow) at each end, that I can only guess is a just a way of making the solenoids water-tight without restricting the piston movement. As each solenoid energises it displaces air out of it's case, and when de-energises it needs to suck it back in. For now, I've just using the breathing end caps that came with the new solenoids. If the actuator engages the transfer case in 2wd, simply swap over the vacuum hoses at the actuator. I've also mounted the solenoid pack next to the actuator instead of up in the chassis so that can keep an eye on it, and for quick replacement if need be. I may even carry one as a spare as they are small and cost peanuts.






Probably not to most folk's standard, but here's what I've done...

View attachment 639894
Thanks BigSky, great descriptions. I think my solenoids look pretty crusty as well, they may well be the problem That's my next step, whilst busy doing so many other things.

I was wondering, with the above picture, is that the FULL travel of the actuation rod to engage the 4x4. I just want to make sure, that what I have been able to clean up so far, is the max. travel. Mine can certainly now be movable with my fingers. I might well follow your solution, but I am not sure if the same parts can be found here. Because you are using "£", I am not sure if you are based in England ?

Or I have in mind a simpler solution, that is to manually insert a piece of wood or something to raising pivot arm one way or the other, to engage and dis-engage. I need to think more on that, as I am not a naturally mechanical person.
 

canter tourer

Adventurer
Great write up Brad, nice fix for the problem.

Ozwanderer, just google the p/n k5t47776 which is in the picture Brad showed, they come up on ebay, .@$38 ea aus, but you can buy them cheaper in bulk, google is your friend.

I too have issues with my vacuum system, only the 4wd one works, not the high/low range one, the wiring in mine is a mess and previously butchers by the old owner. I just lever it with a screwdriver when i want low range, one day I'll find a proper fix for it all, or you may come up with my solution for me :)

On its range of motion, they only move approx 1/2 inch to engage /disengage.

Dave
 
Just an update, but perhaps someone might know something.

Tracing the vacuum hose upstream. discovered no vacuum suction at all at the input steel tube. Try to check if it is cleared, so undo the rubber hose connecting to it just underneath the driver-side chassis rail. Upon undoing the hose, black oil was dripping out the steel tube which is connecting to what seems like the main vacuum tubing ( steel ).


Why would there be oil present in the vacuum system ?

Also there seems to be a network of steel / rubber tubing connecting to the "main vacuum tube", which is metal, and it goes all to way to the front of the engine via the passenger side of the engine, which I presume is the vacuum pump ?

In the network of tubings connected to the main vacuum tube, there seems to be a vacuum reservoir (? ), a black metal box which is placed underneath the front cab, at a corner behind the front underneath the driver kick panel.

Does anyone know what is the network of vacuum tubing do ? Are there other parts of the system needing a vacuum? If so, which are they?

Welcome any pointers.
 
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I haven't needed to look that far up the line. There is a pump? - surely it's relying on the old-school negative pressure at the source of the intake system (before the turbo of course)?
 
I am posting a couple of photos here, and see if anyone can throw any light on what they are. They are all connected to the vacuum network. First of all, I would like to locate the source of the vacuum.

Vacuum circuit-0.jpg Vacuum circuit-002.jpg
 

SkiFreak

Crazy Person
I am posting a couple of photos here, and see if anyone can throw any light on what they are.
My FG84 has a mechanical vacuum pump that is located on the front of the engine.
All information about my truck's vacuum system is detailed in the workshop manual.

If you do not have a workshop manual for your truck, I can only suggest that you get one, as it should answer all of your questions.
 

Aussie Iron

Explorer
A :- is a vacuum Accumulator ( storage tank). The black sludge that you found in the line is probably diesel oil, it shouldn't be there so may be problem with the vacuum pump.
Being a later model than mine it may be different but not much. It should have a vacuum pump on the engine, you need to find it. Take the vacuum line of that and start the engine to see if it sucks at all. Build up vacuum in the tank and follow the lines to where they take you. No one can probably tell you which valve / which line goes where unless they by chance have just gone through their own system. Yes they should be all the same if they are the same model but nobody has probably had problems.
SO LEAD THE WAY AND INVESTIGATE WHAT GOES WHERE and does what.

Let us know,
Dan.
 
A :- is a vacuum Accumulator ( storage tank). The black sludge that you found in the line is probably diesel oil, it shouldn't be there so maybe problem with the vacuum pump.
Being a later model than mine it may be different but not much. It should have a vacuum pump on the engine, you need to find it. Take the vacuum line of that and start the engine to see if it sucks at all. Build up vacuum in the tank and follow the lines to where they take you. No one can probably tell you which valve / which line goes where unless they by chance have just gone through their own system. Yes they should be all the same if they are the same model but nobody has probably had problems.
SO LEAD THE WAY AND INVESTIGATE WHAT GOES WHERE and does what.

Let us know,
Dan.
By reading through the service manual, I gathered that the vacuum pump is part of the oil pump, if that sludge is engine oil, that may mean the pump is faulty, causing oil to flood through, hope not? I shall be tracing it tomorrow. starting from the pump forward.

Does anyone know, if the turbo charger or any other system also use the vacuum line?
 

SkiFreak

Crazy Person
If your vacuum pump was not working you would most likely get an audible alarm in the cab, because one of the vacuum pump's primary functions is to supply vacuum for the braking system, which is what that vacuum container is for.
If there is no vacuum in the system, or the vacuum is low, the alarm will sound as a warning.
 
Hi All

Finally got it sorted, nearly anyway. I now have the actuation working, but not the retraction, I think the worst that could be is one of vacuum solenoids is not working, let's see.

The main issue other than perished rubber tubings etc., is the blockage of the"junction" that connects the thin vacuum line to the front-drive actuation circuit by an appreciable amount of black oil, may be?! I traced upline towards the vacuum pump, there are minute traces of black stuff in the line, but can't be sure if they are oil or just simply a sign of perishing rubber overtime, they are traces.

So now after flushing the line with methylated spirt, and blown dry with compressed air, and let standing the warm weather for a couple of days, I now have the actuation working positively. I can feel the strength of the actuation, it can't be pushed back by hand.

Attached is a simplistic vacuum line diagram, hopefully, someone will find it useful in the future. It is for my FGB71. Sorry, the diagram may meet mechanical engineers standards.




Vacuum System line diagram.jpg
 
Hi All

Finally got it sorted, nearly anyway. I now have the actuation working, but not the retraction, I think the worst that could be is one of the vacuum solenoids is not working, let's see.

The main issue other than perished rubber tubings etc., is the blockage of the"junction" that connects the thin vacuum line to the front-drive actuation circuit by an appreciable amount of black oil, may be?! I traced upline towards the vacuum pump, there are minute traces of black stuff in the line, but can't be sure if they are oil or just simply a sign of perishing rubber overtime, they are traces.

So now after flushing the line with methylated spirt, and blown dry with compressed air, and let standing the warm weather for a couple of days, I now have the actuation working positively. I can feel the strength of the actuation, it can't be pushed back by hand.

Attached is a simplistic vacuum line diagram, hopefully, someone will find it useful in the future. It is for my FGB71. Sorry, the diagram may not meet mechanical engineers' standards.




View attachment 641567
 

kerry

Expedition Leader
Couple of points: Above someone notes that the vacuum and oil pumps are united. That is not the case on the 4d34 to my knowledge. Can anyone confirm or deny this? Second, I believe the exhaust brake is activated via vacuum, or at least it has a vacuum line running to it and apparently a vacuum pod attached to it. That has to be a fairly complex system as it takes input from the accelerator and clutch.
 

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