This is another alternative method for removing broken head studs. It appears to work well and its quite simple. It comes courtesy of Jack Beggs, Editor o f H & HH, Regional Group #67.
In our Dearborn RG #67 we have developed a slightly different system for accomplishing the same task (broken bolt/stud removal) and it does not require any welding skill or equipment that you described in your column. The technique was originated by retired machinist Jim Ogden, and was improved somewhat in the final system described below. Alan Penney, a member of our RG at the time, machined the two sleeves for the use of our members. This method is similar to ideas given by Roger Owens in your column in the Nov/Dec 2001 issue, but we think our technique is a little easier since it does not require using a modified scrap head. The instructions for our members who wish to make this repair are as follows:
The club has two stainless steel sleeves available for drilling out broken cylinder head studs.
The purpose of these sleeves is to drill out broken studs from engine blocks using the cylinder head bolted in place to hold the drill guide sleeves. This procedure is preferred to using easyouts because of the danger of breaking off an easyout in the block and not being able to drill out the easyout due to the hardness of the steel.
The procedure for Ford flatheads (all years to the best of my knowledge) is to ream out the cylinder head hole with a 15/32" drill to get rid of the rust. Then, the sleeves with a 15/32 O.D. should slide into the hole finger tight. Wipe a little oil on the exterior of the sleeve so it doesn't get stuck in the hole.
The first sleeve to use is the one with the inner diameter of 1/4". Some of the old studs are very hard and not easy to drill through, so this drill size will take out a large portion of the old stud as a first step, using 1/4" drill bit. The, the second sleeve with an inner diameter of 23/64" is used to drill out the remaining old material, using a 23/64" drill bit. it will drill through much easier with the 1/4" pilot hole already done. As you drill to the end of the old stud, you will enter the water cavity of the block, so be careful not to press too hard so that you don't go crashing in there and break off your bit inside. You can tell when you are getting close to the end by measuring the threads on the new replacement stud.
The 23/64" drill bit will take out all of the old stud except the threads. Now you will have to remove the cylinder head to finish up the removal. The next step is to "pick out" some of the remaining old stud threads from the threads in the block so that you can start a 7/16"-14 NC. tap which will clean out all of the old threads for the new stud. You need to remove about two circles of the old threads, you will need a sharp tool like an ice pick or something similar. Be patient and careful, and you will be able to accomplish this easily. Once the tap is started, a few turns restores the block threads for the new stud.
The length of the sleeves are roughly 2 and 1/4" to allow enough of the sleeve to stick out of the cylinder head so that you can get a pair of pliers on it if it gets stuck in the head.
When drilling and tapping, you should use, of course, a cutting lubricant like motor oil, or better. Keep the insides of the sleeves lubricated so they don't wear away.
When installing the new stud, a thread sealer must be used because the stud hold is open to the cooling system. Head gasket sealer or any other sealer which can stand the high temperatures should be satisfactory.
Jack Beggs, Editor,
Henry's Hometown Herald
RG #67
If we make taking broken head bolts and studs out any easier, people will be doing it on purpose -- just for fun. Thanks to Jack Beggs and the fine folks in RG #67.