pressurising diffs and gearbox

[KiwiBacon]

you wont blow anythign out the seals are designed to grip the shaft harder with more pressure
you will however increase shaft wear

Go put 10psi into your diff and gearbox breathers. Take photos of the ground before and after.

Any extra pressure will push the seal lip onto a slightly different part of the shaft. Unless that part is completely clean, ungrooved and free of corrosion then it'll start leaking.
Show me a 4wd shaft which is clean, ungrooved and corrosion free.

i have a pile of spares that arnt .....
i spent 5 years in hydraulics rebuiling pumps,motors,rams and repairing broken shit so i saw it everyday
i know for a fact your wrong
your talking .5 or less of movement with 10 psi and disputably it probably wont even shift at all if the you have factory steel backed seals 10 psi ant #### all
if the seal and shaft are in good condition it wont leak if your seal or shaft are damaged then .. its not the pressure making your shit leak its the fact its fucked

oh and my diffs and shit wont leaks ... why because ive just rebuilt them and the surfaces are like new and the seals are brand spanky
perhaps you should be doing more maintance on your own gear if this is a issue for you

Hydraulic seals and diff/gearbox seals are a world apart. The seals on your average diff or gearbox won't take kindly to an extra and unnecessary 10psi. Given that a mere 2psi of pressure can already push water past the seals then they are far from in perfect condition (few used 4wd's parts are).

[KiwiBacon]

again you are talkin out the hole at the southern end of your body,This method is tryed and tested, although not 10psi only about 4 but it does work, doesnt leak and keeps water out.
my bit said
Hopefully mr bacon you are not one of these finger tapping 4wd owners that owns one to get to work and nothing more as you seem to lack the practical knowlege that you get in the mud rather than in a university lecture.

On a positive note, I am about to do a similar thing but with a live bait tank off a boat. 12v and low pressure

If you'd read my post, you would have seen me recommending 2psi.
Obviously you didn't.

Mr "5 years doing hydraulics, lifetime spent tuning cars, wasted years at uni, still doing an apprenticeship" claimed you "wouldn't blow anything" with internal pressure which is pretty silly since water is already getting in with less pressure behind it.

[lilpigzuk]

and so another useful thread will turning into a fawkin tit for tat (with no tittays )

[vvega]

again you are talkin out the hole at the southern end of your body,This method is tryed and tested, although not 10psi only about 4 but it does work, doesnt leak and keeps water out.
my bit said
Hopefully mr bacon you are not one of these finger tapping 4wd owners that owns one to get to work and nothing more as you seem to lack the practical knowlege that you get in the mud rather than in a university lecture.

On a positive note, I am about to do a similar thing but with a live bait tank off a boat. 12v and low pressure

If you'd read my post, you would have seen me recommending 2psi.
Obviously you didn't.

Mr "5 years doing hydraulics, lifetime spent tuning cars, wasted years at uni, still doing an apprenticeship" claimed you "wouldn't blow anything" with internal pressure which is pretty silly since water is already getting in with less pressure behind it.

oh sorry mr i have a cock firmly up my arse
i said that running more than 2psi wouldnt blow your seals as you said it woudl
and as has been posted they have put in more presure and .. it didnt blow oil out there seals as you said
so yet again your posting bulshit

get that cock out of your mouth and enguage ya brain before posting
or perhaps you shoudl send back that degree.. i think they sent it to the wrong person :d

[vvega]

The deepest you're ever going to be is about 1.5 metres.
1.5m gives a static pressure of 2.1 psi.

Any more is just going to blow oil back out the seals.

you wont blow anythign out the seals are designed to grip the shaft harder with more pressure
you will however increase shaft wear

and oh look .. how did that get there
lol

[haynzy]

again you are talkin out the hole at the southern end of your body,This method is tryed and tested, although not 10psi only about 4 but it does work, doesnt leak and keeps water out.
my bit said
Hopefully mr bacon you are not one of these finger tapping 4wd owners that owns one to get to work and nothing more as you seem to lack the practical knowlege that you get in the mud rather than in a university lecture.

On a positive note, I am about to do a similar thing but with a live bait tank off a boat. 12v and low pressure

If you'd read my post, you would have seen me recommending 2psi.
Obviously you didn't.

Mr "5 years doing hydraulics, lifetime spent tuning cars, wasted years at uni, still doing an apprenticeship" claimed you "wouldn't blow anything" with internal pressure which is pretty silly since water is already getting in with less pressure behind it.

I am no scientist and wont do a backyard mythbuster experiment to explain my self but from what I have been told is it is the sudden cooling of the outside diff housing that creates a vacume inside the diff in affect sucking the water in not the other way around. The purpose is to equalise the internal vacume not the outside pressure coming in. This theory has come from experience not a book and I know of one particular vehicle that runs 10psi as that is as low as his regulator will measure and it works fine. Parked in water it blow bubbles but no oil leaks out.

[vvega]

and so another useful thread will turning into a fawkin tit for tat (with no tittays )

simply because you have a very good point

[KiwiBacon]

I am no scientist and wont do a backyard mythbuster experiment to explain my self but from what I have been told is it is the sudden cooling of the outside diff housing that creates a vacume inside the diff in affect sucking the water in not the other way around. The purpose is to equalise the internal vacume not the outside pressure coming in. This theory has come from experience not a book and I know of one particular vehicle that runs 10psi as that is as low as his regulator will measure and it works fine. Parked in water it blow bubbles but no oil leaks out.

Yes the sudden cooling is part of it, but the outside pressure from the water is the rest that pushes water in. 2psi will equalise 1.5m of water, more just puts more unnecessary load on your seals.

If your mates axle is blowing bubbles then it is venting past the seals and some oil will be coming out too (unless it's just the breather). The oil doesn't come out as fast or as much as the air.

[vvega]

i think the point made was if 4 psi is bypassing your seals.. you should probably replace them because .. there stuffed

[haynzy]

[quote="KiwiBacon]

Yes the sudden cooling is part of it, but the outside pressure from the water is the rest that pushes water in. 2psi will equalise 1.5m of water, more just puts more unnecessary load on your seals.

If your mates axle is blowing bubbles then it is venting past the seals and some oil will be coming out too (unless it's just the breather). The oil doesn't come out as fast or as much as the air.[/quote]
I still think you miss the point, its only for driving in water so if you lose 20mls of oil to save 50mls of water coming in at least you dont have to replace the whole 2 litres of oil every two trips. Its like the push button switch I have to turn the electric fan of during river crossings. only used when needed.
me out....

[KiwiBacon]

I still think you miss the point, its only for driving in water so if you lose 20mls of oil to save 50mls of water coming in at least you dont have to replace the whole 2 litres of oil every two trips. Its like the push button switch I have to turn the electric fan of during river crossings. only used when needed.
me out....

I'm not sure what point you think I'm missing. I'm saying use the minimum pressure you have to to keep the water out. More pressure past that doesn't help.

[Satalite]

Its mostly vacume related as stated earlier.

Also, very little oil sits up around the axle seals when the vehicle is level, more when the vehicle is not. Escaping air will obviously find the path of least resistance. That would be through the part of the seal where there is no oil in the way.

Therefore, if the vehicle was on an angle in the water, say the right hand side was lower than the left hand side, the oil in the diff would flow to the right hand side axle seal, and there would be no oil present at the left hand seal. There would be less resistance at the left hand seal, so the air would be more inclined to escape there.

Obviously you would use the minimum pressure necessary to keep teh water out.

Obviously a small oil loss is preferable to completely changing the diff oil.

Obviously the amount of oil loss is going to be dependant on the condition of the axle seals

Obviously the volume of air reqired to maintain the presure inthe diff is going to be dependant on the axle seal condition.

Obviously to much pressure can not be good for anything.

The system works, it is tried and tested.

Lets discuss the finer points of how to extract the most from the idea eh??

[vvega]

Its mostly vacume related as stated earlier.

Also, very little oil sits up around the axle seals when the vehicle is level, more when the vehicle is not. Escaping air will obviously find the path of least resistance. That would be through the part of the seal where there is no oil in the way.

Therefore, if the vehicle was on an angle in the water, say the right hand side was lower than the left hand side, the oil in the diff would flow to the right hand side axle seal, and there would be no oil present at the left hand seal. There would be less resistance at the left hand seal, so the air would be more inclined to escape there.

Obviously you would use the minimum pressure necessary to keep teh water out.

Obviously a small oil loss is preferable to completely changing the diff oil.

Obviously the amount of oil loss is going to be dependant on the condition of the axle seals

Obviously the volume of air reqired to maintain the presure inthe diff is going to be dependant on the axle seal condition.

Obviously to much pressure can not be good for anything.

The system works, it is tried and tested.

Lets discuss the finer points of how to extract the most from the idea eh??

make sure you seals are in good condition

[lilpigzuk]

Lots of tech

Sarah, Im impressed

[DieselBoy]

She's gone back out to the shed, she's busy tuning in the LPG on the VX

[vvega]

She's gone back out to the shed, she's busy tuning in the LPG on the VX

sweet really says something when even a girl can tune lpg in a vx :d
that shit must be easy

[Andrew1706]

Good thing is, after she's used the buckets for the gardening she can clean them out and use them to measure her LPG flow.

Certain Suzukis came with this system didn't they? A friend of mine has one in his LJ50 (LJ80? 2 stroke thing)

[haynzy]

or maybe she is testing putting lpg from a bbq bottle in the diffs

[skid]

baaahahahahahahahahahahahahahaha

lock this shit down

fights over

another one down

[Taz]

Quick!

Wheres PeteFJ40?

Someone needs to get in touch and tell him that this lot is providing more drama than his Coronation Street ever will.

[rokhound]

You are 1 funny cat Taz

End result of this thread is: slight pressure to diffs, g/box, transfer case and Dizzy (if you have one) works. Cheapest and easiest way of doing it is with an elcheapo airbed pump, filling a common manifold (or catch can if you like), that has air lines that run from the manifold to their respective parts (diffs, gbox etc). Make sure that the air that the pump is being supplied with cannot suck water or dirt, and has lots of flow (ie don't restict the pumps' air flow that is coming in). In most cases this means the best place for the air bed pump is inside the cab, and not under the bonnet, although I know of some who have built containers for the air bed pump. I did this with mine at one stage, but it reduced the amount of air the unit could supply and rendered the system fairly useless.

You can argue all the bullshit you want over this, the fact is IT IS PROVEN AND IT WORKS!

[curly12]

Quick!

Wheres PeteFJ40?

Someone needs to get in touch and tell him that this lot is providing more drama than his Coronation Street ever will.

[skid]

Quick!

Wheres PeteFJ40?

Someone needs to get in touch and tell him that this lot is providing more drama than his Coronation Street ever will.

considering it was tuesday nite when ya posted that

he is probably still hiding in the toilet thinking about the episode he just watched and how hot he thought rosie was

[wjw]

Go to KatMandu they have a sale on airbed pump 15$...

The most expensive part is the hoses. I used spare radiator hose and found the right attachment in the pumps box to go into that. Then I have 10mm inner di hose to diffs, gearbox, transfer, spark plugs, and a 3mm to the dizzy. Just need some host clamps and some irrigation T's to join them all together.

[mfrsr]

there's just one thing i can't see here...

Where do the diffs and gearbox vent to when the pump's not running? Into the cab?

Would've thought the oil smell would be a bit disconcerting

[rangimotors]

mine have always vented into the cab and i never notice the smell, I do have a habit of having a few dirty old oil covered rags in the truck though and often some 2 stroke mix etc for the saw so breathers are neither here nor there when it comes to the smell of things..

[albundy]

Shit, I thought that was just my air freshener, seriously I don't notice it.

[Landy Rover]

Well, I bought a 1.5hp compressor minus the motor and pump. I mounted my bush ranger on it, used the existing switch gear and regulator that was on the tank. I fitted a 12v solinoid switched from the dash to feed air into the diffs, gearbox and winch motor. The solinod has a vent port so the diffs etc are vented when not turned on. I set reg at about 5-8psi. Had this for awhile now and has worked a treat. Used to always fill the front diff with water and fawked one winch motor with water. I also use the compressed air for tyres, blow gun etc. Adjusted the presure switch to turn off at 100 psi. Tank with switch gear cost $20 on TM I went through 3 4wd bits compressors Tyfoon double ended, he refunded my money, all of them only lasted less than an hour and all melted down and seized. The Bushranger max just goes and goes.

[darinz]

I've just melted a Typhoon as well. Been using it like you but the low pressure was only to my winch motors. With the number of guys I know using the Typhoon pump it appears it is fine when pumping tyres and other low pressure things but at 100psi for lockers etc they fail and quite quickly.

Most air cooled comp winches use an air bed pump for the cooling so that is also a very tried and proven system.

[fweddy]

What sort of plumbing have others used on their system?

I've got my airbed pump and been looking at plans to fit.

The outlet is 21mm. I was thinking of reducing down to 13mm straight away and running through the fire wall and T off to front diff, then continue to transfer case and T off again and finally continue down to rear diff.

The input to the diff is 6mm ID so I need to reduce it and that seems to be a little difficult to find parts for.

Was looking at the garden irrigation stuff but smallest is 13mm with no reducers.

Another idea was to run a large pipe (20 or 13mm) the length of the vehicle and insert 6mm into that like the irrigation systems use.

I'm thinking it best to keep large diameter for air volume for as far as possible??

What have others used?