Engine breather

[Peter04]

Hi Guys

I have just returned from a 5 day off road trip in the Oman, great riding.
had a couple of problems with the bike.

1. day 2 done a number of river crossings while crossing a deep section not very wide I caught the front wheel against an unseen rock and dropped the bike and yes on the air intake side. It was in the water for only a moment but as we all know thats enough to suck in water and it did 4 ltr of the stuff.
I was doing all the usal tacking out the plugs air filter etc and noticed that the oil viewing window was 3/4 full of water and was not mixed with the oil. So i put it on the back of a pick up back to a local town and drained the oil but out came 4ltr of water first. The only way I can think that it got into the bottom of the engine was to go from the air box via the engine/crankcase breater hose that goes into the bottom of the air box as it was really long enough to get passed the piston rings.
I was thinking of fitting a one way valve to the hose or even removing it al together.
Day 3 the front casing of the starter broke so took out the broken part and it was bump starting for the rest of the way.

Has any one any idea's abot the engine breather hose.

Any info would be great, but not things like dont ride off road, dont ride through water,

Cheers
Peter

 

[(RIP) Bin Ridin]

If you put a nr valve in the hose, I think it will create a vacuum in the crankcase - not sure if that would be harmful but it could affect the shaft seals, suck them in tighter and wear them out. If the bike gets water in engine, you need to change the oil or in emergency at least let it sit, then remove the drain plug and let some drain to be sure there is no water.

Have you drained the g/b and FD oils?

How did the starter front casing break? Did you find a compatible car starter?

Bin

 

[ianp5uk]

You could provide multiple exits if emissions are not an issue. That way it will suck less water if one of the exits/openings is in air. It wont stop all water but maybe you'd have a lot less than 4 litres! The theory being air will flow a lot easier than water and be sucked in preference. It's standard practice on 2 stroke dirt bike carbs. They have 4 vent hoses to the carb. For some reason the manufacturers route them all down so the first water crossing the engine dies. All you have to do is move 2 of them up to the airbox and no more engine stalls in water because the carb will continue to breathe through the ones in air. Could work for engine breathers too?

4 litres is a lot - how long was it under for?

 

[Peter04]

.

It was in the water for a max of 30 sec but i think 1 or 2 revolutions would be enough to fill the air box which proberley holds about 4 ltrs the gear box oil and the final drive is ok but will be cahnged any way just for good mesaure.
It wasnt really under trhe water it was on its right hand side with the water just lapping over the cyclinder.


I would think the starter was broken when I tryed to start it after picking it up as they dont like all that pressure.

when i took out the starter and removed the broken bit (the front of it) i put the starter back in and was pushed from the rear by my friend on his KTM as soon as he got me upn to speed I would bump start it in 3rd, quite good fun for the next 250 km.

Still not sure what to do about the breather.

Peter

 

[TeaPig]

There's no reason why the breather needs to go into the air-box other than to burn any oil mist it emits rather than pump it out into the air. You could simply route a longer pipe to somewhere under the seat and vent it into a catch-tank (old plastic bottle with some sponge in it to filter out the oil), providing that doesn't also go underwater.

Of course the real culprit is the location of the air intake which is what has let the water in. Relocating this is the secret, though difficult to do neatly. If you look at any off-road landrover with a snorkel added you'll get the idea

 

[Peter04]

.

Thanks Tea

I have used Land Rover snorkles for many years, I am at the moment looking for the right bit of piping to route the air intake up under the front by the head stock. Only realy need to use it when crossing water.

Pter

 

[TeaPig]

Sounds like you're on the right track. It may be worth looking at the HP2 just in case that offers a solution as I think it has a high intake and a deflector? . Clearly there's a load of stuff under a GS tank that makes routing a pipe difficult so I can imagine finding the right bits awkward. I guess you've looked at stuff like that corrugated pipe which is rigid enough to prevent collapse but flexible so it'll bend easily?

 

[TrailBoy]

Hi - in case this info is of use - I have found a flexible compression tube which seems to be a good fit for temporary use for the R850GS (and presumably the R1100GS) air intake - the opening of which has internal diameter about 40mm.

This is the Floplast compression waste system flexi-tube 40 mm / 1.5" which I bought in B&Q bar code 5 055149 901423. Cost about £10. It is about a foot long when compressed but will stretch out to allow it to be inserted snugly into the air intake, bent to about 180 degrees to come out under the tank on the left of the bike, then stretched up to the handlebar and hooked using a bungie or similar. Unfortunately it is in a great shade of sink fittings white rather than colour matched to the bike but hey ho! I cut off the screw bit and drilled a hole in the flange so I could attach a bungie.

I think the air intake for the R1200GS is a little wider than 40 mm id and is not quite round although maybe it could still be possible to use this tube and pack it out with some waterproof tape.

 

[Timolgra]

Sorted

 

[Timolgra]

Use anything you can with 1200 in water

 

[Pukmeister]

I haven't been out to the garage to look at my bike, but as I recall, there is a large (1 inch approx) diameter pipe that goes from the airbox to the LH cylinder, a crankcase breather hose. I had a problem with my old 1200 where the hose clamp kept coming loose on this pipe and needed refitting.

I reckon if you dropped the bike and filled the airbox with water, when you picked the bike up the water could simply flow into the crankcase via the breather hose (which you mentioned)and settle at the bottom of the sump (because oil floats on water - it is less dense). When you removed the sump drain plug the heavier water comes out first.

Not sure how it could be rectified unless like Tea Pig suggests you extended the breather hose to go higher than the airbox then back down rather like a U-bend or P-trap so that any water in the airbox can be manually drained out without flooding directly into the sump. A non-return check valve may work (if you can find one the right size), but can you trust it to be watertight ?

A mate dropped his 1200 in morton river whilst fording, and subsequently cranking it over to pump out the water ripped the starter mounting dowel out of the bellhousing (along with a piece of casting).

To make a cheap intake snorkel get a length of vacuum cleaner hose from an old discarded vacuum cleaner (local rubbish tip) and use with a roll of duct tape. Cable-tie the open end to the handlebars. Prevention better than cure.