Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 The "TRANSFER PUNCH" (5/16 or 8mm) will help you punch the stud right in the center. Start off with a small bit, like 1/8 and just get the hole started. STOP! Add some motor oil to the "CUP" you created. DO NOT turn the drill bit too fast. Let the drill bit do the work. DO NOT apply too much pressure. These two things tend to wipe out drill bits. Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/P10100130-3.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 LEFT HANDED 5/32 drill bit............ : SOMETIMES a left hand bit will back out the stud. That is my CHEAPEST drill. (that still works) BUT........it's reversable and........VARIABLE SPEED! Â Slow it down.......it cuts faster. Use some engine oil to lube with. Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/P1010015-3.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 Hmmmm....................that didn't work. And my "easy-out" hates that hole! TOO SMALL! Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/P1010016-3.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 Let's try..............RIGHT HAND 3/16! Â What SPEED...what PRECISION...what WORKMANSHIP!! WHAT........ the hell are you talking about? ;D Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/P1010017-3.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 I'm talkn bout.........SOMETIMES, EXPERIENCE is SMARTER than the DESTRUCTIONS! ARRRRRR! She be mine.......mattys! 8) Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/P1010019-3.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 I know those threads look completely wasted, but they are not. This hole would be STRONGER if you Helicoiled it and you would sleep better. But.........we're not done yet. ALL the studs should GO. In fact.......some will probably break off when I try to extract them. Better now than later! We've got a few tricks that might make this easier. 8) Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/re-tap%20hole%202.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 How about chasing it with a 8mmx1.25 tap followed by a bottoming tap! CHASING OLD THREADS and CUTTING NEW THREADS are two differant things. Â It will be just fine. REMEMBER.....this stud was merely broken off. When a NUT comes LOOSE and VIBRATES the stud..........that's one way the threads are completely destroyed. I'm hoping a thread will SELF DESTRUCT so a Helicoil becomes necessary. If not......I'll just drill out the threads! ;D Shelby said he "has done THOUSANDS of broken studs" (he should turn down his air pressure) doh! Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted November 30, 2004 Report Share Posted November 30, 2004 http://2.6liter.com/userfiles/StarPauser/new%20stud.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 Screwed right in with my fingers! Gee.........how much you think that head is WARPED? Â .005.......008? Stay tuned........we'll find out tomorrow. Â Take a bow, John! :-* I better read the manual..............before I type the text. Link to comment Share on other sites More sharing options...
Tim_C. Posted November 30, 2004 Report Share Posted November 30, 2004 It's been my experience that if you repair a head stud thread, you need to use a helicoil if you want it to be better than before, and not develop the same problem again. The helicoil is stronger than the orginal cast aluminum thread, let alone a hole that had the stud drilled out, and rethreaded. That won't last because now there is less aluminum to hold the stud than there was from the factory cast that already has failed. Several ways to get the stud out. The Professor showed one that works. Once the stud is out, clean up the hole, and rethread it with the helicoil tap. You may need to use the drill that came with the helicoil kit first, to drill it out to that size, and then use the helicoil tap. I have never needed to use the drill. The size is close enough, and the aluminum soft enough to just tap it with the 8mm X 1.25 helicoil kit tap. (The actual tap is not 8mm X 1.25, but a special sized tap for the kit to house the 8mm X 1.25 inner threads of the helicoil.) Clean out the shavings again from the hole. Put Red loc-tite on the outside/outer diameter threads of the helicoil insert, and carefully use the helicoil tool to thread the insert into the hole. The entire insert should go all the way in. If any is hanging out, then the threads are not deep enough, or some debris is still in the hole. It is very important to make sure you get the helicoil tap threaded all the way, with no debris in the hole to keep it from going as deep as possible. The reason this is important, is because it is not so easy to back the helicoil back out, and fix it, without ruining the helicoil insert. So, just make sure the hole is tapped as clean and as deep as possible, before inserting the helicoil. Okay, assuming the helicoil has just been threaded all the way in, or at least far enough to not stick out at all, you now need to put some antiseize on a new headstud, and thread it in, while the Red Loctite on the outer threads is still wet. Now, either bolt up the manifold if you are ready, or if you are not ready to bolt it up, you must tighten a nut to each stud that was fixed, to pull the stud and helicoil to rest against the outer part of the threads. This will allow the red loctite to cure with the threads in the exact position they need to be in, simulating a manifold on there. This helps the threads and loctite a lot to make for a bullet proof, strong stud that will not come out. You will need to stack some washers over the stud before tightening the nut down, so the nut can pull the stud threads outward/to rest against the outer part of each thread in there. Don't overtighten the nuts, and they really don't need to be very tight at all. Use a 1/4" drive ratchet to do it. Let it set overnight, and dry like that. The reason you use antiseize on the stud threads, is to be able to remove them later, without pulling the helicoil with it. Studs need to have the ablility to come out for resurfacing, and other head work that may require the stud to be removed later on in the life of the head. There are other things to do to help the studs, like cutting the webs on the exhaust manifold, and making a support bracket, etc.... Link to comment Share on other sites More sharing options...
Professor Quest Posted November 30, 2004 Author Report Share Posted November 30, 2004 Ahhhh! A relief typist who knows the finer points! ;D Only the top 2 or 3 threads were damaged.........mostly from whatever Mitsu used on the threads. And I totally agree with Tim. Infact, we will be doing just that..........and more as we move along because even Helicoils can't repair some holes but there's a few other tricks. In the long run.........it doesn't make much sense to repair this head at all. But it CAN BE DONE. I would'nt be doing you justice if I simply said........"order a new Marnel". Link to comment Share on other sites More sharing options...
Tim_C. Posted December 1, 2004 Report Share Posted December 1, 2004 Yeah, when the cracks between the valves disappear under the seat like that, they are OK if they don't extand past the seat like those do. If you can detect the crack past the seat, and it pressure tests fine, then it is worth using. If the crack goes beyond the seat to the other side too, then it is junk even if it passes a pressure test. The repair to that takes too much time, costs more than it is worth, and is a waste of money when you can get the new Marnal as cheap as we can now. Worth holding onto for a time when the Marnal may not be so readily available. Link to comment Share on other sites More sharing options...
Professor Quest Posted December 2, 2004 Author Report Share Posted December 2, 2004 I took the head to "C J Casting Repair" today. He looked at the cracks and said they were alittle deep but not much more than average. But as Tim pointed out........it ain't worth it. I asked him to give me details on the crack grinding process........he would'nt do it. "I make my living......blah blah blah " "FINE........we buy them brand new for $325" "REALLY? WHERE?" "I make my living from KNOWING PARTS........SEE YAH! ;D Then I went to the REAL machine shop. Turns out...............I have a KILLER LINE ON NEW HEADS!!! ;D Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted December 2, 2004 Report Share Posted December 2, 2004 http://2.6liter.com/userfiles/StarPauser/which%20thread%20locker.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted December 2, 2004 Author Report Share Posted December 2, 2004 Which would you use? Â ??? Do you know how many "RED" thread lockers there are out there? Blue won't take the temperture........niether will RED............unless it's the one on the left. Here's the trick................only put it on the top 2 theads.....BOTH parts. 450 degree rated. Â FULL Cure time.........UNDER PRESSURE Â (Read Tims reply) Â 24-7. YES.........this takes CONTROL. REMOVAL? Â 500 degress for 5 minutes.........HAND TOOLS. Â "Loctite" makes "246". Good to 400 degress. NO, neither is CHEAP. Â $13 . Â How about you turn the studs up-side down..........just to be safe so your thread locker does not run down the stud. Â Marnel manifold studs will fall out as well. Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted December 2, 2004 Report Share Posted December 2, 2004 http://2.6liter.com/userfiles/StarPauser/P1010011.JPGBare with me, i'm going from memory here ;D.. And you know my mind-state last night :... Link to comment Share on other sites More sharing options...
Professor Quest Posted December 2, 2004 Author Report Share Posted December 2, 2004 Good thing I don't need a metric pipe tap...................cause ain't one here. : Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted December 2, 2004 Report Share Posted December 2, 2004 http://2.6liter.com/userfiles/StarPauser/straight%20edge%20exhaust.JPG Link to comment Share on other sites More sharing options...
Professor Quest Posted December 2, 2004 Author Report Share Posted December 2, 2004 : Well............AFTER you chamfer the holes around the exhaust ports......take the machinist rule and look for warpage. There is NONE on this head.........and I've never seen any on other heads. Link to comment Share on other sites More sharing options...
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