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The idea of MIG welding crossed my mind quickly before he mentioned it too (because I do Arc and Mig welding at home myself).
But it would be very tough and time consuming to file/sand the weld and create a perfect shape. Besides, I doubt that a small weld would hold the extreme pressure at engine operation.
I would be very interested to see the follow up clip from this guy to learn if he ever was able to do it.
 

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Discussion Starter #3
The idea of MIG welding crossed my mind quickly before he mentioned it too (because I do Arc and Mig welding at home myself).
But it would be very tough and time consuming to file/sand the weld and create a perfect shape. Besides, I doubt that a small weld would hold the extreme pressure at engine operation.
I would be very interested to see the follow up clip from this guy to learn if he ever was able to do it.
Exactly what I thought as well. I don’t know of any remedy that would withstand that kind of torque pressure on that crankshaft. The surface is too small.


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in dire need of an organic chemistry lesson
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that would withstand that kind of torque pressure on that crankshaft.
No it won't. The funny part was he was talking using JB weld :lol:. I guess he messed up with the shaft when he was changing the TB and this is a way to correct it. But it won't work.
 

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I wonder if this is what happened to the "ylwagon" which fired normally up for a second, then sounded like a broken belt except the brand new belt is intact and all the marks line up. Been in the garage since Thanksgiving!
 

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It could be. You can put a wrench on the crank bolt and see if there is movement between the crank and gear. I know it's worse on built engines as the stiffer springs and higher revs put more stress on the timing belt which transfers it to the crank pulley. The built 2.0T block I bought has a press-fit gear and an ARP bolt. I don't think it was also pinned. Maybe someday I will install it in my car (if I keep it).
 

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This got me to wondering, so I put a round bar into the #1 plug hole, and rotated the engine while watching for the maximum height of travel. Nearly as I can tell, the pulley mark is still on TDC when the rise of the test bar stops (and cam sprocket marks align). I also couldn't get the crank bolt to loosen when using a long breaker bar. The crank still rotates with effort, but noiselessly.
 

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have done similar repair ,often tig welding is fine ,using stainless rod, what works for me on equipment that has had similar failures either on shaft or a custom fitment pulley or sprocket is to green loctite (sleeve permanent retainer) the two together in correct alignment, after loctite sets up and depending on size, drill and tap a hole from the end of shaft (crank in this case) and pulley ,splitting the difference, you tap by trial and error only enough so that a set screw starts to get tight as it gets flush, once tight it is permanant and as previously mentioned ,once crank is torqued to spec (really tight for those who have done it) there is no where for it to go and shear factor for this is way more than a keyway, i.e, for this application for reference I would use like 10 mm/3/8" set screw. As to dowel pins ,they are brittle due to heat treat and if they break there is no drilling them out..... better off using plain or hi-alloy steel. This probably like mentioned happens a lot and either is mis-dianosed and as like ylwagon says
to physically confirm TDC with piston and its relationship to crank timing mark. Happens alot with front main seal replacement and not proper crank bolt torque, got me worrying now....gonna double check mine this coming weekend....
 

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have done similar repair ,often tig welding is fine ,using stainless rod
I think it depends on the amount TIG applied. If small area I'm not sure if it can hold that kinda pressure. May be it can but that's not my experience with small weld areas.

After you used TIG, did you end up doing filing to get it to the right size/shape? Given the tight area I think the entire frontend needs to be removed.
 

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don't know if it will hold that pressure either ,reason I suggest stainless .... when cooled the chrome has a little compliance especially with an unknown alloy (crank) as it cools you might get hair line cracking or weld itself hardens the steel at the weld joint, have a picture of "set screw repair " somewhere will try and find in next [email protected]
 
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