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I just started a YZ-10 restoration and after some cleaning found this:
The front diff is super-glued together! I assume I can soak in Acetone and break it down...but would you do it in the first place? Poor man's posi?

RedScampi wrote:Poor man's posi?

yes. Some of the guys locally have been doing this in their slash 4x4s. Its ugly and leads to more problems down the road though...
Todd

I have seen this done to the rear diff, but it doesnt make the car work better than a properly functioning diff. other than it never comes loose and causes the car to push like mad. BTW that is a rear diff pulley.

Justjoe wrote: BTW that is a rear diff pulley.

oops, yes, you are correct! My bad.

Thanks for the info guys. It's soaking in acetone now.

she needs a bit of work good project mate

I had a yz10 that had the glue treatmet as well. I gave it an acetone bath and found that there were no diff balls. I guess the previous owner didn't want to buy them.

Actually, your car looks like there's a lot of potential. You have some mugen bull dog tires on it. If you decide to acetone tohse, let us know if the tires survive. There's another member that had questions about acetone and those tires.

don't sweat it. it's just a yokomo prototype one way.

That looks like quite a project! Sometimes though, these builds/restorations are the most satifying as the comparison between the end product & what you started with is so vast. I have a feeling this will clean up well & become a very fine buggy.

BTW we run locked front diffs (or Spools) in our touring cars. It makes for a car with aggressive initial turn-in, better power on steering & braking.

Hey guys, thanks for all the replys and encouragement. I've decided to turn this into a build thread. I agree about the satisfaction of bringing these back from the dead. It's more difficult by far than building new. Each piece has it's own special challenge. The Bulldog tires were toast upon arrival unfortunately. They basically fell apart in my hands. This car is rough but it has good bones. Thankfully I have amassed *ALMOST* enough parts to do a reasonable restoration, I think. I need a backbone (for the car!)
The chassis was hammered but I was lucky to find a really nice one on evilbay. The front magnesium bulkhead was broken too, but I have a replacement. I have several plastic front and rear bulkhead covers in varying condition. None perfect but I think I can make one of each work. One of the cover screws is broken off in the rear bulkhead, pretty much flush. Does anyone have an idea of how to get it out? The diff freed up after a day or too of soaking in acetone. I washed it with soap and water then sprayed it out with WD-40.
Here are some current state pictures. This probably will not be a box-stock rebuild. I just want it to be a nice example. Let me know your opinions and any suggestions.

i have a motor mount that also has a broken off screw. I have been searching on the internet about using alum for dissolving steel screws in aluminum but I can't find any information about if the alum attacks magnesium. My bet is it does, so I think I'm stuck just fixturing it best I can and running a 1 or 1.5mm drill down into the screw and hoping for the best.

nice work so far, i have three in a little bit better condition waiting for restoration

jwscab wrote:i have a motor mount that also has a broken off screw. I have been searching on the internet about using alum for dissolving steel screws in aluminum but I can't find any information about if the alum attacks magnesium. My bet is it does, so I think I'm stuck just fixturing it best I can and running a 1 or 1.5mm drill down into the screw and hoping for the best.

nice work so far, i have three in a little bit better condition waiting for restoration

My worry about running a drill into a steel screw that's fastened into magnesium is that it will slip off and gouge the magnesium. Then there's always the possibility of setting it on fire...

Don't they have special drill bits to extract broken screws?

There's a potentially sparking electric motor that can get very hot pressed right against one of them magnesium parts. Seeing vintage Yokomos did and do not regularly spontaneously combust, a slipping drill likely won't ignite your bulkhead.

According to the almighty Google, you'd have to heat magnesium to over 650*C in order to start it afire. That'd be a tad bit overgeared I would say LOL

If you have a drill press, I would source a small end mill. It will make a staright cut and is not as prone to deflecting like a drill bit will. I am sure that broken screw is not a quality screw but it will be tough to keep a drill bit straight especially if the broken end is not a clean break.

You should be able to pick up a 1 or 1.5mm end mill pretty cheap. Go with a high speed steel end mill and work it in slow with cutting fluid. Your problem screw will be toast and you will end up with a clean, straight hole. A carbide end mill would work great but only if it was a high end, end mill. The cheap ones are vey brittle and you are really screwed if you break a carbide end mill in the hole. Not much out there that will cut carbide without spending a ton of money.

A HSS end mill will work great for this, just a thought.

Jake

RedScampi wrote:Hey guys, thanks for all the replys and encouragement. I've decided to turn this into a build thread. I agree about the satisfaction of bringing these back from the dead. It's more difficult by far than building new. Each piece has it's own special challenge. The Bulldog tires were toast upon arrival unfortunately. They basically fell apart in my hands. This car is rough but it has good bones. Thankfully I have amassed *ALMOST* enough parts to do a reasonable restoration, I think. I need a backbone (for the car!)
The chassis was hammered but I was lucky to find a really nice one on evilbay. The front magnesium bulkhead was broken too, but I have a replacement. I have several plastic front and rear bulkhead covers in varying condition. None perfect but I think I can make one of each work. One of the cover screws is broken off in the rear bulkhead, pretty much flush. Does anyone have an idea of how to get it out? The diff freed up after a day or too of soaking in acetone. I washed it with soap and water then sprayed it out with WD-40.
Here are some current state pictures. This probably will not be a box-stock rebuild. I just want it to be a nice example. Let me know your opinions and any suggestions.

I have an original magnesium rear bulkhead in good condition, it just needs a good clean up. You can have if you donate $10 to the site.