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Tue Oct 27, 2009 9:37 pm

well, this 1977 2.0 has no o-ring and yet no oil comes out it. Nor did my 1971 type 1 need an o-ring so I have to assume something is different.

If you have excessive pressure from blowby it means that something in that breather is blocked.

Other alternatives are that your engine has no thermostat and that it isn't getting hot enough to burn away water that collects in the oil from combustion and that makes it foam. Or it is over filled and the cam and crank are frothing it up.

I am sure that it is nice to have it not leak but you may just be treating the symptoms and not the ailment.

Tue Oct 27, 2009 11:28 pm

There is one reason oil comes up through the dipstick....PCP (Positive Crankcase Pressure) Well, maybe two if you count a really steep hill, or a roll-over...

You can feel happy about your O-rings, I did for a few days, but after a few hundred miles of highway driving, the PCP will push oil out where it can. The dipstick is the lowest "open" point.

Do a "leak-down" test and post the results...

Wed Oct 28, 2009 4:49 am

I do have a functioning thermostat and flaps. Also, The same day as I put the o-rings on, I cleaned out the breather with a large amount of carb cleaner. It had some build up all over, and that buildup is now gone. Hopefully the now gunk-free breather is helping with the pressure issue.

Wed Oct 28, 2009 5:56 am

Quote: I cleaned out the breather with a large amount of carb cleaner.

well, one thing for sure, if the diaphram wasn't perforated before it is now. The diaphrams cannot handle carb cleaner. It dissolves them. Instead of too much pressure you will now have too little pressure. Watch for valve gaskets sucking in now and keep your eyes open for a good used one. They are not available new. To clean them, they can handle soap and water, gasoline, kerosene and stoddards solvents. Carb cleaner dissolves them almost instantly. I found that out the hard way while cleaning one and verified it with articles on the properties of silicone rubber - which the diaphram is made of.

Wed Oct 28, 2009 6:03 am

I already have my buds in the parts biz looking for a replacement, just in case the one I had was bad anyway. Looks like it just became a higher priority. I didn't know about the diaphram properties, thanks for the info.

Wed Oct 28, 2009 6:39 am

I learned the hard way cleaning one with spray carb cleaner. If you find a source for new ones please let me know. I have been looking for over a year and all that are out there are used ones. Hoody found the last NOS one in a closed dealership and if he has found more he isn't telling anyone. I ran an ad on Samba for a year, featured at times offering name your price and no one responded except used ones. They can be rebuilt with care but not until someone makes a replacement diaphram so don't toss it if you find a replacement. I have a bid on making new diaphrams but don't have the $1500 right now to make 100.