Water in chassis tube - guessing not good?

Diffs, axles, lockers, transmissions, portals, that kind of thing.
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spandit
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Water in chassis tube - guessing not good?

Post by spandit »

Drove my Pinz for the first time in a month after getting back from some extreme off-roading a while back. Only moved it onto the drive so I could service the brakes but when I stopped (my drive is slightly sloped) I noticed water dripping out of the rear locker switch cover. I undid the bolts and it poured out - a good couple of litres, I'd say.

a) How did this water probably get in there?
b) How do I make sure there's none left in there?

On the plus side, the water looked fairly clean - wasn't mega rusty or anything
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Robin

Pinzgauer 710K
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4x4Pinz
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Re: Water in chassis tube - guessing not good?

Post by 4x4Pinz »

replace locker light cover gasket and wire grommet, replace gasket at locker slave cylinder and if you have a vented housing make sure tube is secured higher than water mark. Not a big deal but water is hard on some of the parts inside the housing as there is no oil to keep things from rusting and the electrical switch does not like being wet.
spandit
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Re: Water in chassis tube - guessing not good?

Post by spandit »

Thanks - it's quite warm today so hopefully it will dry out a bit (hope so, just been pressure-washing the brakes - couldn't believe how much crud was in there - had to remove the shoes to get at most of it!)

If mine does have a breather/vent, where does the tube come from? I've got a breather tube in the engine bay - could this be it?
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Robin

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4x4Pinz
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Re: Water in chassis tube - guessing not good?

Post by 4x4Pinz »

the breather tubes are usually run up to the bottom of the body, at least the ones that I have seen.
Here is the breather kit
http://www.pinzgauer.com/showdetails.ph ... 102283300/
pretty much self explanatory from the picture where is goes.
spandit
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Re: Water in chassis tube - guessing not good?

Post by spandit »

Thanks - I'll have a scout around - definitely looks like the one in my engine bay so presume it goes to the front locker from there
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Robin

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Re: Water in chassis tube - guessing not good?

Post by Dreadnought »

Get an airline in there and give that chassis tube a good old dose of wax oil!!! Well that,s what you used to do on Landrovers!!!!! Just a note, I offroad just to go to the shops and I was amazed when I took off my drums after a whole year to find that the brakes were relatively clean dry and working. (relatively = compared to a Landrover which fills up it,s drums with a mud water/clay mix if you even show it a puddle). but seriously looking at the Pinz set up how well engineered it all is and so 'close fitting' (yes I know they are a swiss watch and cost a lot when new!! but they are just so GOOD!!!)
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GenevaPinz
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Re: Water in chassis tube - guessing not good?

Post by GenevaPinz »

Hi Guys,

I follow my habit of piggybacking on an existing same-topic thread instead of starting a thread of my own.
I will send my truck to Scotland once more next month and will have to ford a river 4 times a day for 2 weeks. Right now my truck is not fitted with the breather kit because it is not available anymore from SAV, but I had a good look while their website had a picture of it (it is assembly no. 24 here: http://www.pinzgauer.com/parts.php?cat= ... view=03-25).

So I purchased part no. 19 from the drawing in the link above (the locker switch cover plate with a short lenght of pipe welded to it), plus a length of 5/16" rubber tube and clamps from McMaster and a small filter from Summitracing with same-diameter fittings. All I need is some luck as I will need to salvage and re-use the locker light wire grommet. Otherwise I will have to apply a good bead of RV sealant to serve as grommet (probably will be even more waterproof). So I basically assembled the elements of a factory differential breather kit from separate sources...


In the factory setup, the breather's top end is near the engine air filter. I don't really look forward to being sitting behind the wheel in a cold scottish stream in the middle of January with water up to my chest, but if it was to happen I'd rather not have my engine quit on me at that point, so I have fitted a DIY temporary snorkel (takes about 10' to fit, and it is mostly a flexible tube going from the air filter housing through the tunnel and out of the front grille, which connects to some pipes going around the windshield and a "mushroom filter" at the top corner) to avoid the risk of hydrolocking if water was to be higher, so I will end up with a differential breather tube that sits well below my snorkel level...

So my question is this: do you think it is a good idea, instead of letting the breather tube in the open and around the engine air filter, to drill a hole in the engine filter housing, set a pipe fitting of the correct dimension, and connect the top of the breather tube to the air filter housing? This way it prevents any water ingress at this level. My worry is that there will be some vacuum in the engine air filter housing... I know the differential will be somehow "isolated" from the air filter housing by the small filter, and the locker switch cover is not in direct contact with differential oil (the locker switch is in between), so there should be no risk of oil being sucked up the breather tube, but I wonder what your take is on this.

Thanks!
Jan

'72 Pinzgauer 710M
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TechMOGogy
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Re: Water in chassis tube - guessing not good?

Post by TechMOGogy »

Interesting - how many #19's did you buy 3?
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Jimm391730
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Re: Water in chassis tube - guessing not good?

Post by Jimm391730 »

My 712W came with breather kits from Swiss service. The front diff breather does go up under/behind the air filter, but the rear breather (which is supposedly able to vent both rear diffs) goes up only to the underside of the body, near the top of the tires. I have heard that there is enough passage through the diffs that one vent should be sufficient in the rear of a 712.

If you anticipate DEEP water (higher than the rubrails) then yes, you should probably put both vents up even higher, and venting into the fresh air intake would be fine. Before or after the filter should not have enough pressure difference to matter (if the diffs are two feet under water, then they already have 1 psi of external pressure on them). One reason for the vents is that if a warm/hot diff is suddenly cooled through submersion in cold water, the internal air will cool, shrink, and create a vacuum internally that can overcome the seals and suck water inside. Venting breaks the vacuum and then the seals only need to exclude water and the pressure at that water depth.

But I can't see any issue if both vents are plumbed together into one hose, and that hose vents into the intake air from the snorkel. I'd install it towards the top of the air filter, so any water that might get into the bottom of the filter does not drain into the diffs.

I would take great care to ensure that the ignition system (wires, dizzy and cap) are truly waterproof as many of us have had ignition problems at much shallower water crossings than you seem to be contemplating. If you don't have spark, you will be in deep water! (pun intended). :cry:
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GenevaPinz
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Re: Water in chassis tube - guessing not good?

Post by GenevaPinz »

TechMOGogy wrote:Interesting - how many #19's did you buy 3?
Actually I bought only one as from the little "research" (with a good dose of google translate) that I did over the German forum, I found out that venting, even at the front only, apparently does cover the full chassis front to back. And as long as there are vent holes inside the diffs that allow pressure to equalize with the half-axles, they are covered as well. This last one can only be ascertained by taking the diffs apart (but I won't do it just for that) as it was not part of the build process during the early years and was apparently retrofitted in Graz when trucks were undergoing repairs / refurbishment at the factory. So I assumed I did not need to buy 2 (for my 710) or 3 (if I was part of the 6-wheeler club).
I'm not sure my '72 ever got the interior vent holes in the gears to allow the half-axles to breathe, but at least I will have the diffs covered...
Jim, it is interesting that your truck has a breather on one of the back axles, too. I am not convinced the guys on the German forum have it figured out more than you do. But venting this one does present a challenge as the gain in fording height is indeed limited unless the breather tube is extended all along the truck. Well noted about ignition: I might well try WD-40, a thick rubber glove and zip ties over the distributor cap (one lead through each finger).
Most of the times the river is nice and low, 2 feet or so, maybe 3 feet tops. But it can be higher, or worse be low in the morning and getting much higher for the return trip. I won't push my luck, and with the breather I am trying to add peace of mind more than anything...
Jan

'72 Pinzgauer 710M
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ScottishPinz
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Re: Water in chassis tube - guessing not good?

Post by ScottishPinz »

GenevaPinz I hope you will be stopping by to say hello while in Scotland!! Where about are you visiting, which river are you crossing?
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GenevaPinz
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Re: Water in chassis tube - guessing not good?

Post by GenevaPinz »

ScottishPinz wrote:GenevaPinz I hope you will be stopping by to say hello while in Scotland!! Where about are you visiting, which river are you crossing?
Hey,
Same exact story as last year: viewtopic.php?p=64801#p64801
The river is Glen Lochsie, which runs through Dalmunzie Estate, there are two fords on the way up which goes almost to the top of Glas Tuleichan (the local high point). We won't linger long near Edinburgh except on the way in and out, but I'll let you know where we are and when. It would be really nice to meet!
Jan

'72 Pinzgauer 710M
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