93 VFR750 RC36 Posted July 18, 2010 Share Posted July 18, 2010 I'm replacing my old rusted exhaust system and managed to snap off one of the studs on the front head. Fortunately it broke off at the base of the nut so there is a bit of stud sticking out to get hold of. What should I do to make sure I don't snap off this or any other of the studs inside the head? I've got some Plusgas but will it work on easing the studs in the head? I want to get all the studs out and replace them. They're all 17 years old and the forward ones are pretty well rusted. Time for new studs/nuts. All advice welcome. Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted July 18, 2010 Member Contributer Share Posted July 18, 2010 Removing studs is a lot easier if the engine block is up operating temp... this is true because metal expands and more importantly the space around the metal also expands... Link to comment Share on other sites More sharing options...
Member Contributer kgsmotorcycles Posted July 18, 2010 Member Contributer Share Posted July 18, 2010 Drilling the studs out is a bitch of a job!!...Try to avoid it. Use everything in your Arsenal.. Cheap stud extractors might make things worse.. Good luck soldier... :biggrin: Link to comment Share on other sites More sharing options...
Member Contributer Cogswell Posted July 18, 2010 Member Contributer Share Posted July 18, 2010 If you've got enough meat sticking out - maybe - a pair of vice-grips after the pen. lube can work it loose. If not you're probably going to have to drill the stud and use an extractor to get it out. Hopefully you have room to get a drill in. If not, maybe a Dremel can get in there to drill it. Be sure to drill straight or the threads will be toast. The extractor should have a recommendation on drill size. Lots of links like this on a Google search. http://www.brokentap.com/easy-outs.html Once out, be sure to use some high temp copper anti-sieze on the nuts (not the regular type) to keep from going through this again. Best of luck. Link to comment Share on other sites More sharing options...
93 VFR750 RC36 Posted July 18, 2010 Author Share Posted July 18, 2010 It's a bit difficult to get it up to temperature, it's got no carbs on it at the moment. Can I achieve the same thing with a butane torch to gently warm the head around the stud? What's the torque limit on these studs? If I stick to using my torque wrench I can probably avoid twisting off another. Link to comment Share on other sites More sharing options...
Member Contributer Cogswell Posted July 19, 2010 Member Contributer Share Posted July 19, 2010 The factory book for 90-94 model years shows 9 foot-pounds for the header to cylinder head nuts. No spec listed for seating the studs in the head. There may be a manual available on the site for download. Link to comment Share on other sites More sharing options...
Member Contributer IntAceptor Posted July 19, 2010 Member Contributer Share Posted July 19, 2010 If you can get to it easily, take a file and flatten the protruding section of the stud. Take a file or dremel tool metal wheel and make a slot that a flat screwdriver will go deep into. Take a propane torch and heat the stud and the area around it and attempt to unscrew the stud. If that doesn't work, grab it with the vise grips and try again. Generally heat does a much much better job than the best of any liquid wrench type products. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted July 19, 2010 Member Contributer Share Posted July 19, 2010 ok.. this is going to sound counter productive.. BUT IT WORKS>>>> :cheerleader: 1st.. id you do indeed have enough room for a stud remover or vice grips.. dont heat around the head.. HEAT THE STUD UNTIL ITS RED HOT!!! :fing02: then remove it! i am not kidding!! i 1at saw this method for removing broken studs an harley wheels.. the reasoning works like this.. the bolt is steel.. the wheel or head is aluminum.. its stuck due to corrosion bonding the 2.. you cant heat the head deep enough to burn off the mess.. but you can if you heat up the bolt.. yes it will expand.. but heat leaching into the head opens the hole.. :fing02: Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted July 19, 2010 Member Contributer Share Posted July 19, 2010 Can I achieve the same thing with a butane torch to gently warm the head around the stud? Not worth the trouble... aluminum is a great heat sink... you'd have to torch the whole block... What I would do is remove the head... remove valve guide seals... set head in oven... heat to 300F... then tackle all the studs Link to comment Share on other sites More sharing options...
Member Contributer BusyLittleShop Posted July 19, 2010 Member Contributer Share Posted July 19, 2010 dont heat around the head.. HEAT THE STUD UNTIL ITS RED HOT!!! :cheerleader: then remove it! I've seen this idea work too... it's worth a try... map gas torch is a better heat source than propane bottle... Link to comment Share on other sites More sharing options...
Guest Posted July 19, 2010 Share Posted July 19, 2010 when i did this, i rolled a nut onto the few remaining threads and had a buddy tack weld it in place. then i just wrenched the nut and stud combo out. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted July 22, 2010 Member Contributer Share Posted July 22, 2010 so 93 VFR750 RC36.. did you get the bloody stud out or are you still on a tea break toasting the queen?? :mellow: Link to comment Share on other sites More sharing options...
93 VFR750 RC36 Posted July 22, 2010 Author Share Posted July 22, 2010 Being a Canuck I don't drink tea. I've been toasting HM with port (RAF tradition) for years, occasionally a glass of Bushmills or Rye is used. Anyway, no I haven't got it out yet. Been distracted by stripping and cleaning the carbs and getting a bone spur cut of my heel. I'll let you know when it's done. Stew Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted July 22, 2010 Member Contributer Share Posted July 22, 2010 the bone spur you can do yourself with a dremel :cheerleader: have fun with carbs and make sure you tip the strippers. :lobby: Link to comment Share on other sites More sharing options...
Guest Posted July 22, 2010 Share Posted July 22, 2010 The factory book for 90-94 model years shows 9 foot-pounds for the header to cylinder head nuts. No spec listed for seating the studs in the head. There may be a manual available on the site for download. From member of UK forum "When installing the new studs, remember the short thread goes into the head and run the stud into the head until the shoulder snugs up (finger tight) against its seat." Just finger tight, may be why Honda don't give a tightening torque. Tony Link to comment Share on other sites More sharing options...
Guest Posted July 22, 2010 Share Posted July 22, 2010 Further tips from a mechanic: "NEVER try with the engine cold, I have had to fix no end of these when someone had tried to undo it on a cold morning and it sheared" - so application of heat is important - and "The other tip is once the stud starts to turn, if it stiffens up, back off gently and ease it on again, keep going like this until it comes out (use light machine oil to help it out) " More advice: "If you break a stud and cannot get a grip on it, try and use a stud extractor as a drill and tap is likely to ruin the original machining." Best of luck Link to comment Share on other sites More sharing options...
93 VFR750 RC36 Posted July 22, 2010 Author Share Posted July 22, 2010 I suggested a bottle of whiskey and a dremel to my wife but she didn't approve. In the end I went through the normal medical process, call me unadventurous if you will. I'll be gentle with these studs to get them out. I'll definitely be using heat to get the nuts off and then use a combination of heat, Plusgas and gentle fiddling to get the studs out of the head. I may use a radiant heater for a few hours to warm the whole block up and then use my torch to apply local heat. I'm hoping that a bit of gentle persuasion should have them all out this weekend. Link to comment Share on other sites More sharing options...
rodm850g Posted July 22, 2010 Share Posted July 22, 2010 [Guys, I went through this one on a different bike last year. I have an oldSuzi GS850G...I lost 5 of the original8 bolts....I useda Time-Sert kit from Wholesale tools...they are listed in the Fastenal cataloge or site as well....Yes its a lot of work but I found them better than a heli-coil. drill out bolt, re-tap and insert new threaded device that is threaded on the outside to new threads and correct pitch for the stud....when done correctly as it is installed the ends are flared locking the insert into the head or whatever part of the motor you are working in....one can also stake the outside of the insert to the machine as well....Good luck Rod Link to comment Share on other sites More sharing options...
Member Contributer thereisnospoon Posted July 22, 2010 Member Contributer Share Posted July 22, 2010 If you need to drill it, grind it off flat (if it didn't break flat) then center-punch it just enough to make a divot to hold the drill bit while it starts I don't know about the heat being applied when getting a steel bolt out of aluminum, there have been plenty of occurrences where hot bolt and hot aluminum results in the bolt taking the aluminum threads out right along with itself. I think if you could cool (like freeze) the bolt, then heat the aluminum around the area the bolt will come out because steel shrinks when cold... liquid propane or something... Link to comment Share on other sites More sharing options...
Guest Posted July 22, 2010 Share Posted July 22, 2010 1. Buy a new head. 2. Buy a new stud. 3. Buy a top end gasket set. Write it all off to expensive experience. Link to comment Share on other sites More sharing options...
93 VFR750 RC36 Posted July 25, 2010 Author Share Posted July 25, 2010 The tea break is over, the studs are removed and the new exhaust is on (see my thread about Sandy Bike Spares left exit exhaust). After breaking off the first stud at the base of the nut, I decided to take more care. Left to right as you look at the head from the front: 1. Broken at base of nut (first one, kicking off this thread). 4. Heat, spray with Plusgas when warm, wait 10 minutes, heat so top of nut just shows red, apply gentle torque - stud comes out of head (clean threads). 3. Heat, spray with Plusgas when warm, wait 10 minutes, heat so top of nut just shows red, apply gentle torque (spot the theme) - nut comes off stud. 2. Heat . . . - stud snaps at base of nut "Bugger!" 3. Two cycles of heat tip of stud to red, Plusgas while cooling, hit stud with pipe freeze until frosting - then heat until tip is red, wait 20 seconds and apply gentle torque with vice grips - stud comes out clean. 2. This takes 3 cycles of the same - stud out clean. 1. This takes 5 cycles of the same - stud out clean. I found that as soon as I had a bit of movement of the stud, I brought it out 1/2 turn, hit it with Plusgas and then wiggled it back and forth 1/8th of a turn. Plusgas penetrated very quickly and the stud was then removable by finger power only after only 10 wiggles or so. All of this may have taken less time if I could have run the bike to heat the block/head. However, it has no carbs, tank or battery at the moment so that wasn't a player. The multiple heat cycles resulted in the head warming a bit which probably did the trick. Unbelievably all the threads were perfect once I got past the initial trouble at the head surface. Plenty of copper high temp anti-seize grease and the new studs went in beautifully. Just a note about 3-in-1 spray copper high temp grease - I saw it and wondered what it added that normal copper grease didn't. Answer - 1. More mess where you don't need it. 2. Less grease where you need it. Basically, if you can't get to a component with your finger or a twig or chopstick or whatever to put on some grease, then this stuff is the bee's knees. As the last 36 years has seen that has happen to me exactly the same number of times I've been to the moon, I'm not convinced. That said, it does work so I'll now be wasting time in the garage trying to find things that, "that spray in copper grease would work on this." Stew Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted July 25, 2010 Member Contributer Share Posted July 25, 2010 :fing02: :bliss: :bliss: :biggrin: awesome!! glad it all worked out for you! now remember when i visit you guys over there one day.. you must show the best local eats.. NO fish n chips! :fing02: Link to comment Share on other sites More sharing options...
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