In my opinion, anytime you lessen a torque value on any metal gasket that holds back large quantities of pressure, you must reseal the surface with material that has correct sealing properties. The nice thing about air coolded engines is that you are only trying to keep pressure in and you don't have any fluid to worry about, so there is no need to use sealers. That being said, if you un-torque your head bolts, you must, in my opinion, replace the head gasket. If you are using copper, you can return the material to it's original soft composition by annealing it. This can easily be done, but ***is different than steal***. With steal, you heat then quench to harden it. With copper, just the opposite is true. You heat the copper with a torch to at least 800deg F, then water quench it. It will soften to it's original state. You can then reinstall it. A concern of this method is oxidation, but it is a long term concern. Rule of thumb: Heat until cherry red, throw in a tub of water, remove, dry, and let cool all the way. Then use...
As for the steal base gasket, remember, on the corvair, that base gasket doesn't hold back combustion pressure, only minimal crankcase pressure and oil. If you didn't disturb the position of the cylinder, you probably don't have to replace the base gasket. If you did disturb the cylinder, don't anneal the gasket, just put some sealer on it and you should be fine. Replace or anneal the headgasket if you untorqued the bolts. Not only will you save your head from the damage caused by leaking combustion gasses, but you'll also save your life. Again, just my $.02. Better yet....I think I'll buy a horse. :-) Scott --- Joseph H Horton <joe.kr2s.buil...@juno.com> wrote: > Scott, > In your opinion would I have my engine at risk of > the same thing > happening? I just tore down last week and replaced > the crank shaft in a > corvair. I did not replace the copper head gaskets > or the steel base > gasket. It is not turbo but is the 3100 cc. I have > run it for 10 min. but > only up to 1800rpm. > Thanks > Joe Horton, Coopersburg, Pa. > joe.kr2s.buil...@juno.com > > On Fri, 9 Sep 2005 05:08:41 -0700 (PDT) Scott > William <scot...@yahoo.com> > writes: > > If I may offer this: The reason I asked about > your > > head gasket is because you did as I suspected. > Just my > > $.02 here on your work....but when you loosened > the > > nuts, you should have removed the head, > re-annealed > > the copper gasket, and reinstalled and torqued. > Once > > the torque is removed from copper, it will not > > properly reseal (combustion pressures)unless it is > > replaced with a new one, or annealed to soften it > back > > up. In a turbo motor such as yours, this is > imperative > > because of the increased combustion temps. > > > > Again, just my $.02 from years of building air > cooled > > stuff... > > > > If you want to know of a good annealing process, > I'd > > be gld to offer. > > > > Scott > > > > --- Orma <o...@aviation-mechanics.com> wrote: > > > > > Yes, burned under the copper gasket and > eventually > > > through the copper > > > gasket. I'm going to talk to my VW guy today > and > > > have him look at the > > > head.. The color of the deposits in the head, > look > > > to be on the lean side. > > > The gas escaped at the top. Which is where I > had > > > removed the nuts to > > > install the cht senders. There was torque on > the > > > nut, when I went to remove > > > them, it's just that the gas escape pattern > suggests > > > that there was > > > looseness at the top. With the turbo putting > more > > > pressure on the engine, > > > the problem may be other. When I get back to > the > > > plane today, I'm going to > > > play with the other head and see what the torque > is > > > like on that side. > > > > > > Orma > > > Southfield, MI > > > KR-2 N110LR 1984 > > > See Tweety at > http://www.kr-2.aviation-mechanics.com > > > See other KR spces at > > > www.kr-2.aviation-mechanics.com/krinfo.htm > > > > > > > > > > > > _______________________________________ > > > Search the KRnet Archives at > > > http://www.maddyhome.com/krsrch/index.jsp > > > to UNsubscribe from KRnet, send a message to > > > krnet-le...@mylist.net > > > please see other KRnet info at > > > http://www.krnet.org/info.html > > > > > > > > > > > > > > > > ______________________________________________________ > > Click here to donate to the Hurricane Katrina > relief effort. > > http://store.yahoo.com/redcross-donate3/ > > > > _______________________________________ > > Search the KRnet Archives at > > http://www.maddyhome.com/krsrch/index.jsp > > to UNsubscribe from KRnet, send a message to > krnet-le...@mylist.net > > please see other KRnet info at > http://www.krnet.org/info.html > > > > > > _______________________________________ > Search the KRnet Archives at > http://www.maddyhome.com/krsrch/index.jsp > to UNsubscribe from KRnet, send a message to > krnet-le...@mylist.net > please see other KRnet info at > http://www.krnet.org/info.html > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
