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Old 08-26-2010, 11:45 AM
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Default Help with my engine

So i went to change out the bearings in the clutchbell and the 8 mm screw that I lock tight in snapped as I was trying to get it out. What's the correct size of drill/tap i need to get?
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Old 08-26-2010, 11:47 AM
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Originally Posted by Snowbum32
So i went to change out the bearings in the clutchbell and the 8 mm screw that I lock tight in snapped as I was trying to get it out. What's the correct size of drill/tap i need to get?

get a dremel, and use the cut off wheel and put a cut on the front of the screw and use a flathead to remove the screw.
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Old 08-26-2010, 11:57 AM
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Originally Posted by tc5 man
get a dremel, and use the cut off wheel and put a cut on the front of the screw and use a flathead to remove the screw.
The screw head snapped completely off and the threads are still inside. No room to put a cut.
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Old 08-26-2010, 11:59 AM
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Originally Posted by Snowbum32
The screw head snapped completely off and the threads are still inside. No room to put a cut.

oh thats a tuff one i guess a drill bit would work not sure.
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Old 08-26-2010, 12:10 PM
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Go to Lowes or Home Depot and get the 4 piece easy out extractor kit, heat the end of the crankshaft with a lighter to break the bond the loctite has and use one of the extractors to remove the broken screw.
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Old 08-26-2010, 12:17 PM
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you have (2) options as far as saving that crank.

#1 grind down the nose of the crank just enough to meet the snapped screw so that youll be able to slot the face of the scew, then use a verry small "flat" screw driver to remove it, if that works you will have to alter shim count behind clutch bell "inner" bearing.

#2 go to hardware store and buy screw extractor and follow appopriate steps, being that the screw is like a 3mm it is so small that it will be practically impossible to drill the center of that screw without dammaging the crankshaft's clutch bearing mounting surface. #1 is best bet

luck'
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Old 08-26-2010, 12:21 PM
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Thanks for the help. It broke pretty flat so I hope that means im lucky today and a drill and tap will work
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Old 08-26-2010, 12:26 PM
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Originally Posted by Slider30250
Go to Lowes or Home Depot and get the 4 piece easy out extractor kit, heat the end of the crankshaft with a lighter to break the bond the loctite has and use one of the extractors to remove the broken screw.
+1 works great think there 20 bucks
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Old 08-26-2010, 01:02 PM
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If for some reason you cant get it out or you damage the end of the crank, you can buy a clutch nut that has the shaft on it. You cut the end of the crank off to the threads. Once installed you can cut off a little of the shaft to fit(I had to cause it took way too many shims and rubbed my fuel tank).
I did this for my Nova 821B when I blew the end of it off using a flywheel puller.
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Old 08-26-2010, 01:34 PM
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Default 3-0.5mm screw removal

Originally Posted by Snowbum32
So i went to change out the bearings in the clutchbell and the 8 mm screw that I lock tight in snapped as I was trying to get it out. What's the correct size of drill/tap i need to get?


I would suggest giving damaged item to one of your machinist friend and and again suggest the following: preheat crank end with good heat gun, and use a 3/32" left hand drill bit. Best to chuck up crank in lathe chuck, rotate counterclockwise a low RPM, very carefully spot (center drill) and peck drill using your LH drill bit chucked in tailstock. If the threaded area is free by heat source the broken thread will walk its way out the shaft end before you peck drill 3/4 thru broken screw length. From this point chase thread with 3mm-0.5 tap, blow out debree and done. Its very difficult to do this free hand with a hand held drill motor, as drill bit will flex and walk on you drilling off center. good luck
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Old 08-26-2010, 05:41 PM
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Originally Posted by RayA
I would suggest giving damaged item to one of your machinist friend and and again suggest the following: preheat crank end with good heat gun, and use a 3/32" left hand drill bit. Best to chuck up crank in lathe chuck, rotate counterclockwise a low RPM, very carefully spot (center drill) and peck drill using your LH drill bit chucked in tailstock. If the threaded area is free by heat source the broken thread will walk its way out the shaft end before you peck drill 3/4 thru broken screw length. From this point chase thread with 3mm-0.5 tap, blow out debree and done. Its very difficult to do this free hand with a hand held drill motor, as drill bit will flex and walk on you drilling off center. good luck
Thanks that is what I was looking for was the size. Thanks
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Old 08-26-2010, 05:41 PM
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Originally Posted by Miniracer23
If for some reason you cant get it out or you damage the end of the crank, you can buy a clutch nut that has the shaft on it. You cut the end of the crank off to the threads. Once installed you can cut off a little of the shaft to fit(I had to cause it took way too many shims and rubbed my fuel tank).
I did this for my Nova 821B when I blew the end of it off using a flywheel puller.
Ill try that if I screw up. Thanks
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Old 08-26-2010, 05:59 PM
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this is why locktite on the crank scares me. I have had one screw back out in almost 2 years. It's just not worth it.

I did put locktire once on it, and what just happened to you was very close to happening to me.
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Old 08-26-2010, 06:06 PM
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Originally Posted by dreaux
this is why locktite on the crank scares me. I have had one screw back out in almost 2 years. It's just not worth it.

I did put locktire once on it, and what just happened to you was very close to happening to me.

just dont put a lot of blue locktight and its fine just use a dab thats it .
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Old 08-26-2010, 06:22 PM
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Originally Posted by RayA
I would suggest giving damaged item to one of your machinist friend and and again suggest the following: preheat crank end with good heat gun, and use a 3/32" left hand drill bit. Best to chuck up crank in lathe chuck, rotate counterclockwise a low RPM, very carefully spot (center drill) and peck drill using your LH drill bit chucked in tailstock. If the threaded area is free by heat source the broken thread will walk its way out the shaft end before you peck drill 3/4 thru broken screw length. From this point chase thread with 3mm-0.5 tap, blow out debree and done. Its very difficult to do this free hand with a hand held drill motor, as drill bit will flex and walk on you drilling off center. good luck
BINGO!!! Take Rays advice, with years spent as an automotive machinist I've seen hundreds of broken bolts. The left handed drill proceedure has the high success rate.

Don't be afraid to use loctite. Very few people know how to use it correctly. I'd estimate that 98% of users apply way too much loctite.
Imagine how much space there is between the threads of the screws in our cars/trucks. Anything over 1/4 of a drop is way too much. After applying loctite to a screw you should still be able to see every thread.If not, you've used too much.
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