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Sun Dec 30, 2007 12:55 pm

put one on and last nights cruise....it would smoke out of first sometimes...1500 i just did the top end on , runs real good, need to check drivers side valve clearance......pass. are fine. oilbath cleaner and stock set up are intact....solex 28. ive got to go but ill check back later thanks, i searched but never found a concise answer. seems to betiny bit more oil in the cleaner also. thank you.

Sun Dec 30, 2007 1:17 pm

420GOAT wrote: put one on and last nights cruise....it would smoke out of first sometimes...1500 i just did the top end on , runs real good, need to check drivers side valve clearance......pass. are fine. oilbath cleaner and stock set up are intact....solex 28. ive got to go but ill check back later thanks, i searched but never found a concise answer. seems to betiny bit more oil in the cleaner also. thank you.

Huh?

Sun Dec 30, 2007 1:30 pm

Prior to the early 1960s, automobile gasoline engines ventilated directly to the atmosphere through a simple vent tube. Frequently this consisted of a pipe (the "road draft tube") that extended out from the crankcase down to the bottom of the engine compartment. The bottom of the pipe was open to the atmosphere, and was placed such that when the car was in motion a slight vacuum would be hopefully obtained, helping to extract combustion gases as they collected in the crankcase. The system was not positive though, as gases could travel both ways, or not move at all, if conditions were just right. Modern diesel engines still use this type of system to dispose of crankcase fumes. During World War II however, a different type of crankcase ventilation had to be invented to allow tank engines to operate during deep fording operations, where the normal draft tube ventilator would have allowed water to enter the crankcase and destroy the engine. The PCV system and its control valve were invented to meet this need but the need for it on automobiles was not recognized.

via wikipedia
I still don't know what would be considered this on the VW engine, I guess the overflow tube from the oil filler maybe?

Sun Dec 30, 2007 3:01 pm

420GOAT wrote: put one on and last nights cruise....it would smoke out of first sometimes...1500 i just did the top end on ,.

What do you mean "it would smoke out of first sometimes." ?
The tube should have a little rubber boot on the bottom too, I think its supposed to act as sort of a one-way valve; letting oil weep out of it and releasing pressure, but its not supposed to allow stuff to get sucked IN.
In almost 20 years of VW's I've rarely worked on a car that the boot installed/ or not cracked badly.
Anyway..get one of those on there...and let us know what your original (or "O.G."?) question is..
peace! we ouwtta heere!

Sun Dec 30, 2007 5:35 pm

That would be # 57 here:

VW calls it a "water drain valve"!! and it is part number 253 260 180.

http://www.busdepot.com/details.jsp?partnumber=253260180

Strange that it is used on vanagons for the A/C drains.....

Sun Dec 30, 2007 6:16 pm

My 36hp in my '55 Bus would put out fumes there sometimes when cold. It never concerned me as I just figured it was burning off or expelling water that had collected inside the breather overnight.

If it did it when warm, I would be concerned I was burning oil.

Sun Dec 30, 2007 8:15 pm

i guess my question is , will a draft tube sometimes cause more pressure than wanted ........seems after i put it on, the car would smoke out of first but no other gears.....i understand it has to do with pcv system.

Sun Dec 30, 2007 8:23 pm

I've had to modify the ones from WCM because they don't open up like they're supposed to. It's important that the pressure has a place to go.

Sun Dec 30, 2007 8:28 pm

Naaah..w or w/o the tube the case is still vented to the oil-bath via a hose, right? What was your setup before the road draft tube?
And...1st gear is pretty damn short in a bus, I would NEVER even have time to glance back and notice the smoke between getting moving and shifting to 2nd.
A common place for case pressure to be relieved is through bad seals or behind the crank pulley, IF you for some reason a massive amount of pressure or a big engine that is.
Do you have the little boot on the end? What exhaust? Maybe little drips of oil /condensation are dripping off the end of the draft tube and burning on the exhaust?
Take it off some jumps, that'll fix it.

Mon Dec 31, 2007 10:32 am

big bus mike wrote: I've had to modify the ones from WCM because they don't open up like they're supposed to. It's important that the pressure has a place to go.

Agreed, once working they will relieve pressure correctly

Mon Dec 31, 2007 10:40 am

The rubber tip/draft tube is maybe one of the most miss-understood things on a VW engine for some reason. It's not for oil or pressure release but for water to drip out, make the air-cleaner suck out gasses, and to keep out dirt. If you glug in a quart of oil then, yeah, some oil will drain out there. Early engines had nothing but a fill hole and cap. Then, kinda like the Wikipedia thing, the breather pipes were added to vent out crankcase gasses which cause leaks and potentially could explode. If it has the rubber boot then it must have the aircleaner vacuum line or it will actually make the engine leak worse or get dust in the oil. If it has the aircleaner hose then it must have the boot or it will suck dust all the time. On short runs or in wet and cold conditions there forms a condensation of water that occasionally drips out the road draft tube by way of that ingenious baffle in the filler and the slit in the rubber cap. Once in a while that filler/baffle should be removed and cleaned out totally. A 1500/1600 single port intake gasket fits better than an og gasket. In '67 and on up California smog laws were mistaken to include an STP device but in reality the only piece of "smog equipment" required on the small displacement of the 4 banger was the rubber tip so crankcase gasses couldn't escape without being burned one more time through the breather system. There will be a test at the end of the semester.

Mon Dec 31, 2007 12:39 pm

No need for breather box. PCV, never an issue! :P

Mon Dec 31, 2007 1:32 pm

BarryL wrote: The rubber tip/draft tube is maybe one of the most miss-understood things on a VW engine for some reason. It's not for oil or pressure release but for water to drip out, make the air-cleaner suck out gasses, and to keep out dirt. If you glug in a quart of oil then, yeah, some oil will drain out there. Early engines had nothing but a fill hole and cap. Then, kinda like the Wikipedia thing, the breather pipes were added to vent out crankcase gasses which cause leaks and potentially could explode. If it has the rubber boot then it must have the aircleaner vacuum line or it will actually make the engine leak worse or get dust in the oil. If it has the aircleaner hose then it must have the boot or it will suck dust all the time. On short runs or in wet and cold conditions there forms a condensation of water that occasionally drips out the road draft tube by way of that ingenious baffle in the filler and the slit in the rubber cap. Once in a while that filler/baffle should be removed and cleaned out totally.

You have it exactly correct. I went through this same explanaton a few weeks ago and gave up. There were some people who just would not listen to facts.

Mon Dec 31, 2007 3:45 pm

I've had to modify the ones from WCM because they don't open up like they're supposed to. It's important that the pressure has a place to go.

this is the one im using and i lengthened the cut but never made a hole or anything....is that what you did? i checked my drivers sidew valves and they were at 0 lash. i then got em to .006 and things seem fine for now.

Mon Dec 31, 2007 4:01 pm

i am curious as to why these new replacment boots don't release the water trapped there correctly. what modifications have you made to fix this problem? thanks for the advice on this boot at the bottom. i remember reading about it in bently but didn't think much of it. i have a stock air cleaner and have an open tube on the bottom. makes sence that the air cleaner would suck dust through the bottom of the tube. time to order one i guess.

Mon Dec 31, 2007 5:27 pm

Karl wrote:

VW calls it a "water drain valve"!! and it is part number 253 260 180.

http://www.busdepot.com/details.jsp?partnumber=253260180

Strange that it is used on vanagons for the A/C drains.....

Must be the new part number - maybe it works better than the ones that WW and all of the other VW parts houses still sell under # 311 115 541 - same price for either one from busdepot

http://busdepot.com/details.jsp?partnumber=311115541

Mon Dec 31, 2007 8:09 pm

VW still sells VW ones and they are kickass. The slit doesn't let out pressure. The carb/air-cleaner breathes out air/gasses from the oil-fill/ breather and creates negative pressure inside the block.