OutdoorEnvy 1,766 #1 Posted February 19, 2022 So decided to pull the crankshaft out of the K241 and all is going well until I get to the two lock screws on the clutch pulley. The first one in the key way backed out fine. The second one, not in the key way, has rounded off, I have tried a reverse drill bit kit. It's eaten up all the bits as the screw must be hard. It hasn't broke loose and now I'm worried I'll drill into the crank if I go further. I have extractors but they widen out to quick to fit down the hole enough to reach the screw/bolt. The allen heads I can't get to bite into it when I hammer them down....It's hit the discouraging point. Any tips from anyone who has had this before? I'm close to just drilling the whole thing out and into the crankshaft thinking I'll clean and smooth it up so the pulley can go back on after the rebuild. 2 Share this post Link to post Share on other sites
Pullstart 66,690 #2 Posted February 19, 2022 Can you measure how deep to go and drill down with a pointed bit, then run a flat nosed bit in the hole to finish the edges out? Share this post Link to post Share on other sites
Pullstart 66,690 #3 Posted February 19, 2022 Generally, I tap a larger hex key or better yet torn bit into the rounded set screw before drilling it. The shock of the hammer often loosens the threads. 3 Share this post Link to post Share on other sites
Maxwell-8 4,367 #4 Posted February 19, 2022 When i have a stripped Allen, I always hammer a bigger torx or Allen ranch into that bolt. soak it in oil and then they almost always come out 1 Share this post Link to post Share on other sites
squonk 43,780 #5 Posted February 19, 2022 (edited) How are you planning on pulling it off? If you use a puller that uses bolts that thread into the face of the pulley, sink them in good and you can probably pull off that pulley with the screw still in there. I've done it a bunch of times on AHU pullies that the screws are rounded or seized. Takes more power but it will come off. Clean up the crank the best you can and when you get the engine running, Leave the pulley off and sand the shaft smooth with emery. Edited February 19, 2022 by squonk 2 2 Share this post Link to post Share on other sites
ranger 1,798 #6 Posted February 19, 2022 Torx bits always seem to work well in these situations, (they do for me anyway). I’ve got a set of extractors that look just like Torx bits. Easy out tapered type ones, I find tend to expand the bolt in the hole, and defeat the object! 1 Share this post Link to post Share on other sites
OutdoorEnvy 1,766 #7 Posted February 20, 2022 7 hours ago, squonk said: How are you planning on pulling it off? If you use a puller that uses bolts that thread into the face of the pulley, sink them in good and you can probably pull off that pulley with the screw still in there. I've done it a bunch of times on AHU pullies that the screws are rounded or seized. Takes more power but it will come off. Clean up the crank the best you can and when you get the engine running, Leave the pulley off and sand the shaft smooth with emery. I am planning to use a pulley puller as you describe. I used it on the flywheel but the bolts in the kit are all too big for the tapped holes on the pulley of course. Anyone know the thread size of those on the pulley? I will see if I have a torx that can reach down to the screw to be hammered into it. I will wear that option out before trying the pulley puller with the screw still in there. Trying to avoid buying more kits. Seems every project comes with more tools too. With the set screw in the key way I can't believe they even need a second one. Thanks for the help all. I'll post an update with how it goes. Share this post Link to post Share on other sites
Snoopy11 5,718 #8 Posted February 20, 2022 (edited) 8 hours ago, squonk said: you can probably pull off that pulley with the screw still in there If it was me @OutdoorEnvy... I wouldn't even try to remove the set screw that is rounded out. I haven't had much luck with rounded out allen set screws in pulleys... I would use... even a regular style gear puller, and replace the pulley if it bends/breaks upon removal. The pulley shouldn't bend/break... particularly if you use a 3 jaw gear puller... If you decide to pull out the pulley without removing the set screw... you SHOULD be able to put it back on without removing the set screw... IF the pulley doesn't bend/break... but I would buy a new pulley, without a doubt... Just my 2 cents. Don Edited February 20, 2022 by Snoopy11 1 Share this post Link to post Share on other sites
squonk 43,780 #9 Posted February 20, 2022 1/4" thread on the pulley holes. 1 Share this post Link to post Share on other sites
OutdoorEnvy 1,766 #10 Posted February 20, 2022 Success! Hammering in the torx bit worked! It got harder as it came up but got it to the top and was able to tap out the crankshaft. Now for some muriatic acid to remove the aluminium. Project can now proceed! Thanks for the help all! 3 Share this post Link to post Share on other sites
Snoopy11 5,718 #11 Posted February 21, 2022 2 hours ago, OutdoorEnvy said: muriatic acid to remove the aluminium safety glasses and gloves please. That stuff in your eye is not fun... Don 1 Share this post Link to post Share on other sites
953 nut 59,896 #12 Posted February 21, 2022 8 minutes ago, Snoopy11 said: safety glasses and gloves please. That stuff in your eye is not fun... Don Take it outdoors too. The fumes are nasty! 1 1 Share this post Link to post Share on other sites
Snoopy11 5,718 #13 Posted February 21, 2022 8 minutes ago, 953 nut said: Take it outdoors too. The fumes are nasty! Plus, it will rust every piece of steel around... Don 1 Share this post Link to post Share on other sites
OutdoorEnvy 1,766 #14 Posted February 21, 2022 I plan to do a baking soda and water rinse after and pick a sunny day to let dry in sun well. Then I’ll put a light coating of oil on it. Just hoping the crank journal is in spec. Rod that broke was a .010 under already 1 Share this post Link to post Share on other sites
Snoopy11 5,718 #15 Posted February 21, 2022 4 minutes ago, OutdoorEnvy said: I plan to do a baking soda and water rinse after and pick a sunny day to let dry in sun well. Then I’ll put a light coating of oil on it. Yeah, normally what I do... is pull it out of the acid, and put baking soda directly on the crank first... which neutralizes most of the acid... Then, like you say, soda and water mixture. Just be careful buddy. I almost lost an eye once... and like to warn people about stuff like that whenever I have the opportunity. Don 1 Share this post Link to post Share on other sites
