Wildguzzi.com
General Category => General Discussion => Topic started by: brider on May 29, 2019, 02:44:42 PM
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I was browsing thru my old original printing of Guzziology, and came across the section on valve cover venting. Dave acknowledges the problem with the Cal 2-vintage Tonti engines with the square covers, and how they are notorious for retaining water vapor. I've witnessed this first hand, and even posted about it here a year or so ago.
I also found a layer of the white mayo in the bottom of my sump, after the bike had sat for over a year, and I can only assume it was residual vapor in the engine? Looking at the internals from the bottom AND top (I pulled the cyls and replaced the rings and valve guides), the engine was without corrosion (thank heavens).
But back to the valve covers; Guzziology says the method of venting them involves tapping into the heads, which I did not do when they were off. I'll go back and read this because it kind of baffles me now, but.....
Wouldn't it be an easy task to adapt a barbed nipple to the valve covers themselves, and plumb that back to the breather system? Granted, I did away with my stock airbox so there is no "intake" duct to tap into, so there's that, but is that the only stumbling block to this idea?
If the stock air intake WAS there, and I WERE to plumb into it from the valve covers, would I also need to add a 2nd passive vent to the valve covers so as not to pull a vacuum, sucking oil up the valve guides?
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The stock breather hoses are already in the head on a California II.
http://www.harpermoto.com/parts-lookup/1980-89-moto-guzzis/california-ii-1000-1983-1986/cylinder-head.html
They are not just vents but drain back as well IIRC, I don't remember that engine having the traditional drain back tube at the back of the engine.
Is Guzziology suggesting that you add yet another hose to the head or VC to vent it? IT would be much easier to use a newer oil that doesn't suffer this issue.
Hunter
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The stock breather hoses are already in the head on a California II.
The link to the Harper's catalogue shows an inset with additional parts 44 - 48. However, my parts manual for the Cal2 does not show those parts; is it possible that Guzzi added a vent hose to the Cal2 for the later years? Mine (a 1984 model) didn't have a vent, and didn't have any provision for a vent.
I found that for short (less than 100 miles) trips, the white goop could show, but for longer trips, that was not a problem, even in very cold weather.
(http://www.dankalal.net/wildguzzi/Annotation%202019-05-29%20151026.jpg)
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Looking back with my young memory (73 yrs young) the valve covers vent into the frame just at the end of the gas tank. There is a nipple on each side (facing forward) on the cross piece , they look like Zerk fittings, then its vented into the frame, I have also seen hose leaving the frame and going back to the air box. These hoses are on the bottom of the cross piece at the end of the tank. I also seem too remember that there is one large hose going from the top rear of the crankcase to the large frame tube near the steering neck (this hose doesn't have a very long lifespan)
Problems are at least this, inside of the frame receives the hot oil mist into a cooler frame , condenses into snot like substance blocking the hoses , nipples , and the frame blocking the venting system, then the vents don't work as designed , I assume this was a quick method to meet the EPA regs at the time.
This is assuming the stock setup now going on 40+ yrs old.
TOMB
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…the valve covers vent into the frame...
I wonder if Guzziology covers this? Some models had vents and some did not--even for the same model year. That being the case, it would not surprise me to hear that you'll find covers with and without vents on the same model--perhaps whatever was available in the box at Mandello.
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I've never seen square-fin rocker covers with vents, only vents in the heads that served the same purpose. FWIW, the early Cal II engine I bought for my "Ambovert" project had no vents, just a bump where they would have been.
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Here is the application.
Lower right in pic
(https://i.ibb.co/FgCjZyC/engine-cylinder-head.jpg) (https://ibb.co/FgCjZyC)
Here you go. Hope it helpes
TOMB
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I've never seen square-fin rocker covers with vents, only vents in the heads that served the same purpose. FWIW, the early Cal II engine I bought for my "Ambovert" project had no vents, just a bump where they would have been.
The images that Hunter and TOMB are referring to are oil feed lines I believe, not vent lines. Guzziology refers to the bosses/bumps on the Cal 2 heads that Charlie refers to, and mentions that this is where a vent SHOULD be added. I did not read this section of Guzziology until AFTER I had re-installed my heads, and I don't want to pull them off now.
So again: Would an open-air vent in the rocker covers (thanks, Charlie!) help at all in venting some of the condensate in the covers, if the bike is used routinely for short-ish trips?
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(https://i.ibb.co/Df7pdmB/20190529-211033.jpg) (https://ibb.co/Df7pdmB)
No they are not oil feed lines what I am referring to they are the vent lines ,which are on the head ,the oil feed lines are also on the head in the middle either directly behind the spark plug closest to the tank ,or if you're facing the cylinder the top bolt that is buried down inside the cylinder head, those are the oil feed lines that works very similar to all the big block see the vent lines are behind those towards the rear of the head take another look at the middle of the heads.
Eariler round heads oil line is attached to the front of the head.
Oil feed in middle ,vent nipple to the right,(rear of head). Other side similar
Tomb
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Bump
TOMB
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Oil feed in middle ,vent nipple to the right,(rear of head). Other side similar
Got it, I saw the oil feed lines in your image from the parts catalogue and didn't see the vent line next to it.
My heads do not have the vent nipples. Oil lines only.
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On the later squarefins the 'Vent' hoses to the heads are actually the condensate return lines from the frame and a lot of the time will be filled with a mixture of rusty snot and mayonnaise!
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Pete, thanks for your input.
TOMB