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What, you never heard of "Eyes in the back of their head"?
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Goofs & Blunders You Should Avoid.
- Thread starter David S
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I have rebuilt several of these gearboxes over the years, but Saturday evening, I was ripping along tearing this one down and forgot a silly little step- remove the speedo housing before pressing out the shaft. Oops. I'm still trying to decide if this is going to be a $500 mistake or a $900 mistake, that's the difference between a used replacement and new billet. That cuts into the plans some... I think the case was cast by Nabisco, because it snapped like a wheat thin.
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Not a chance, the stock case is overloaded to begin with. I could probably do it justice with MIG push-pull, but there is too much fracture damage around structures on the back side of the case to make it a convenient repair. This one is going to have to be be a full-retail fub up if I want to trust it on the remote trail.
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- Jan 25, 2015
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Nah, not too hard. I do it all the time on old intake manifolds.
But it all depends on what type of aluminum alloy was used in the casting, how porous the casting is and how many contaminants are entrained in the cast…
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A guy I know, repairs British bikes mostly. He saves broken cases to use as filler in repairing other cases. He tries to stay within the makes and years so that he has a good chance of making a seamless repair. Cleaning, cleaning again as many times as required helps a ton. His experience is in welding aircraft components and the finish product is impressive.
My lesson for May:
I was welding up the front brush guard of my church's tractor, and needed to smooth my craptastic 6011 stick welding down a bit. Couldn't get a flap sander into the spot, so I used a carbide burr on a die grinder.
Carbide burr grinders make 2.4 bazillion needle-sharp chips every second and a half. They are like living nanobots seeking to embed themselves into the nearest human as part of a plan to take over the world. The mistake is: Don't use welding jig magnets when making those sorts of chips. It's been a couple of weeks, and I'm still digging chips out of my fingers using my very expensive watchmaker tweezers. The chips stand straight up on the magnet with the sharpest point aimed out, turning the magnet into a chia-pet porcupine. Next time, the magnets get moved to a different building and the burr gets used only when the chips can be aimed right into a shop vac.
But there was a good trick I learned: The kind of duct tape that uses that worthless gooey adhesive that has no redeeming qualities whatsoever works pretty well at pulling sharp chips off a magnetic welding jig.
Rick "20x microscope and sharp tweezers getting a lot of use this week" Denney
I was welding up the front brush guard of my church's tractor, and needed to smooth my craptastic 6011 stick welding down a bit. Couldn't get a flap sander into the spot, so I used a carbide burr on a die grinder.
Carbide burr grinders make 2.4 bazillion needle-sharp chips every second and a half. They are like living nanobots seeking to embed themselves into the nearest human as part of a plan to take over the world. The mistake is: Don't use welding jig magnets when making those sorts of chips. It's been a couple of weeks, and I'm still digging chips out of my fingers using my very expensive watchmaker tweezers. The chips stand straight up on the magnet with the sharpest point aimed out, turning the magnet into a chia-pet porcupine. Next time, the magnets get moved to a different building and the burr gets used only when the chips can be aimed right into a shop vac.
But there was a good trick I learned: The kind of duct tape that uses that worthless gooey adhesive that has no redeeming qualities whatsoever works pretty well at pulling sharp chips off a magnetic welding jig.
Rick "20x microscope and sharp tweezers getting a lot of use this week" Denney
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That crack does not look like it involves a bearing surface except the case seal. I'll bet it could be TIGed back into shape. It would depend on the alloy although I have seen good results with castings. Is there a chunk of metal missing there? My other concern would be weld porosity and leaking but that could be sealed. Believe it or not, most factory aluminum castings are porous and are often sealed with something.
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There is a lot more fracture damage on the other side at the speedo housing. I talked on the phone yesterday for a long while to the guy who had been producing a billet replacement. It was fun talking to someone else who has been playing with these Suzuki micro trucks for 20 years as well. He asked about my engine build, and I told him about it, and he told me about some articles that a guy had written on that platform as an information resource. I said that was me, and it all clicked. Turns out he isn't producing the part right now, COVID ruined his contract with the local shop that was running the part. So that idea's toast, I just pulled out my CC and ordered an OEM case from India. I don't know if it is NOS, salvage, Japan, or India production. It is a $450 gamble that I hope works out. It's like playing black or red at roulette, it either pays 2:1 or I lose!
