• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Resurfacing cylinder block andh ead

  • Thread starter Thread starter jhillier449
  • Start date Start date
J

jhillier449

Guest
I'm going to give the used cylinder head and block a little surface mill in my CNC machine at work.

It will remove the old gasket and remove any imperfections so as to give me a good mating surface for the new gasket.

Would removing a few thou cause any issues? Will the valve piston clearance still be ok?

1980 GS1000G

Cheers

John
 
Last edited:
Thanks Ray, I was hoping to hear from you.:clap:

Cheers

John
 
I don't think you need clean metal all the way across, just around each hole, the cam chain tunnel, and around each stud hole. There is often corrosion under the gasket, and milling the head to remove all these marks means quite a bit more cutting than is necessary to have a proper head seal.

Photo below shows a head I had milled. Machinist guy said the marks are of no significance and talked me out of wanting to cut it further.


IMG_1039.jpg
 
Ed..Is that just "marks from the old gasket or is there some pitting? How much more would have been neeed to get it finished all the way..another .005 or so?
 
I don't think you need clean metal all the way across, just around each hole, the cam chain tunnel, and around each stud hole. There is often corrosion under the gasket, and milling the head to remove all these marks means quite a bit more cutting than is necessary to have a proper head seal.

...

I'll second that and go a little further. The only stud holes that need to be cleaned up fully around them are the two at the back corners where the oil comes through. Even there you have a little breathing room if your gasket kit has o-rings there (I think they all do). The band around each cylinder that needs to clean up isn't very wide. If you look at the head gasket, there will be a ring of exposed metal around each bore, and that's all that seals the combustion gasses. The rest is there just to support the head. I had similar marks on my 850's head, only more widespread. Pearson gave it a clean bill of health after doing nothing more to it than repairing some tapped holes and showing me how to clean the old gasket off with a green Roloc wheel.

In fact, I'd recommend cleaning the gasket off with the Roloc wheel first, then see if you need to mill it at all.
 
Back
Top