Cleaning Threads for Head Bolts - NCRS Discussion Boards

Cleaning Threads for Head Bolts

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Patrick H.
    Beyond Control Poster
    • December 1, 1989
    • 11608

    Cleaning Threads for Head Bolts

    Hello All,

    Posted this earlier as a follow-up question, but no responses, so thought I'd try once more...

    In running a thread chaser down the holes into which my head bolts (1971 350/270) will attach, what is the easiest way to make sure the old sealant and goop doesn't end up falling into the water jacket or wherever? Or do I even worry about it? My plan is to have the shop vac running over the hole as I go, but I'm sure that some little pieces will still fall down.

    Any suggestions?

    Patrick
    Vice-Chairman (West), Michigan Chapter NCRS
    71 "deer modified" coupe
    72 5-Star Bowtie / Duntov coupe. https://www.flickr.com/photos/124695...57649252735124
    2008 coupe
    Available stickers: Engine suffix code, exhaust tips & mufflers, shocks, AIR diverter valve broadcast code.
  • Bill #34162

    #2
    Re: Cleaning Threads for Head Bolts

    Patrick: I just did this project over the weekend. I don't know if there is really a fool proof way to do it. I plan on flushing the cooling system with a hose prior to hooking up the rad hoses. Hopefully that will flush most of the schmutz out. Will also change the oil before start up to try to get the stuff that fell in to the pan. I did use the shop vac to minimize the amount going in there. I used a stiff bristle bottle brush with a solvent soaked rag over it to clean the threads before chasing them with the tap. I inserted the brush and twisted, then pulled it out. So, hopefully most of the debris didn't go into the pan or water jacket. The solvent rag on the brush also gives you a good indication if the threads are actually degreased. Keep repeating the process until the rag is relatively grease/dirt free. Good luck.

    Comment

    • Joe L.
      Beyond Control Poster
      • February 1, 1988
      • 43193

      #3
      Re: Cleaning Threads for Head Bolts

      Patrick------

      I don't think that there's much that you can do to prevent it other than using the vacuum as you describe. However, the cooling system of your engine is probably far more contaminated with other things so I wouldn't worry too much about this. Just make sure that you do a complete cooling system flush after you get all of the work completed. You should do that anyway. Use a Prestone flushing kit (the kind that you hook up a garden hose to the fitting you put in the heater hose). Give it a good, long, flowing flush. Then, after you're done, replace the heater hose so you remove the fitting.
      In Appreciation of John Hinckley

      Comment

      • Gerry Proctor

        #4
        Re: Cleaning Threads for Head Bolts

        You can liberally coat the tap with grease. This will collect a lot, but not all, of the junk in the threads. Follow-up as Joe recommended. I did a very good job of removing 25-years of sediment from the bottom of my water jacket by taping off the entire top-end with duct tape and cutting out the water jacket passages. I used a 0-degree nozzel for my 1,500psi pressure washer and a thin metal dowel to agitate the sediment so it would flush out the water pump holes in the block. I followed that up with further agitation and a sucking-out with a shop vac with a small tube adapter to get to the bottom of the jacket. It took a while to get everything out, but now the engine never overheats even with long periods of stop-and-go traffic.

        Comment

        • Kurt B.
          Very Frequent User
          • July 31, 1996
          • 971

          #5
          Re: Cleaning Threads for Head Bolts

          I need to also do this same procedure. My block will be going to a machine shop for assembly so my question is this: If I clean the threads with a tap, will all the dirt and crud be removed automatically when the machine shop cleans the block and degreases everything prior to assembly? In other words, do I NOT need to worry about this or must I still do the flushing thing. The block is completely bare, no crank, no cam, no pistons, nothing. Thank you for help and suggestions.

          Comment

          • Joe L.
            Beyond Control Poster
            • February 1, 1988
            • 43193

            #6
            Re: Cleaning Threads for Head Bolts

            Kurt-----

            I would hope that the machine shop will chase the threads before installing the cylinder heads. In any event, ask that they do.

            After you install the assembled engine and get it running, I would still recommend a complete and thorough flushing of the cooling system. You don't want any flakes or particles of steel/iron settling in your aluminum radiator where they will initiate corrosion of the aluminum.
            In Appreciation of John Hinckley

            Comment

            • Mark Ring

              #7
              Re: Cleaning Threads for Head Bolts

              Kurt, I like to do all the thread chasing at teardown. Do every hole in the block. It is a good idea to do this before it goes to the shop for several reasons. Pull all the soft plugs and screwed in gallery plugs out and strip everything off. You will know a bit more about the state of the core and you are sure that the cleaning will be more thorough. The gallery plugs can be difficult to remove as they are hot fitted but an oxy-acetalyne torch and a can of WD-40 will help them come right out. Take the bare block to the do-it-yourself carwash and tip the block up on it's nose, then squirt the high pressure wand through the deck holes and watch all the crud come flowing out of the water jackets (WOW!). Now you will feel much more secure about the final product. Good luck with your new motor.

              -Mark.

              Comment

              Working...

              Debug Information

              Searching...Please wait.
              An unexpected error was returned: 'Your submission could not be processed because you have logged in since the previous page was loaded.

              Please push the back button and reload the previous window.'
              An unexpected error was returned: 'Your submission could not be processed because the token has expired.

              Please push the back button and reload the previous window.'
              An internal error has occurred and the module cannot be displayed.
              There are no results that meet this criteria.
              Search Result for "|||"