Kyosho Nitro Crusher restore and upgrade

[doutrnz]

Here is my completed restore of my Nitro Crusher that has been with me for over 25 years. The project has been on going for 4 years locating original replacement parts and upgrading all the electronics. There are a lot more pictures of the process but the thread only allows 10 images.

 

[WoodiE]

I love these old trucks. What else are you needing before the build is complete @doutrnz?

 

[doutrnz]

I love these old trucks. What else are you needing before the build is complete @doutrnz

I'm currently replacing parts/rebuilding the engine. This is the original OS engine. I'm looking for a current equivalent carb for it. Adam Drake already resized the sleeve and internals. It runs, but the seals are leaking. After that, I'm going to move on to replacing all the bearings with ceramics. Then it will be complete and will look for another project to start on. I'm also rebuilding an HPI eSavage for a client. That has my priority right now.

 

[monstertruckier15]

The engine is a old .21 RFB. I have boxes of new and used engines and parts. I currently have 5 of these trucks. The best engine was the .21 RXB @ 2.5 hp. but I have .21 RG in my running truck. Parts are interchangeable with the Burns, I have lots of parts.

 

[doutrnz]

The reason I have not switched out the original engine is because the exhaust is too close to the shock towers and I haven't been able to find a modern day, new engine to replace it with. (The exhaust/header is 90 degrees right off of the engine.) If you have any replacement options or workarounds, I am completely all ears!!!

 

[monstertruckier15]

What you have is not original.
Kyosho Exhaust Manifold (OPS) for OS/Mondial Parts# 39515 | eBay
and silicone coupler tube.
You won't find any modern day motors to fit. The crankshaft is different now. Changed to a pilot shaft.
You will have to stick with older motors with a threaded crank shaft.
O.S OS Max RG 21 R/C Engine RC car boat plane | eBay

 

[doutrnz]

I bought the engine new 25 years ago. I should know, its original. The manifold/header and exhaust is what I've managed to manipulate into the small area. I still have the original parts of the exhaust except the large rubber part that connects the manifold to the exhaust pipe. That dry rotted away unfortunately.

Will the engine you linked from ebay work with modern day exhaust so it fits on the truck?

 

[monstertruckier15]

I was referring to the exhaust. Not the engine. The engine I linked will work with the manifold I linked and tune pipe you have. The manifold will work only with some engines. The one I listed works with Os. Once you find the correct parts any current tune pipe will work. As I have explained to you the current engines all use a pilot crankshafts that will not work with you kit. You need a engine with a full threaded crankshaft to attach the clutch nut too. Your kit is 25 yrs. old and finding part today is very difficult. I was buying parts as fast as I could and now it's almost impossible to find parts. The usa-1 nitro crusher and burns use most of the same parts. Ebay is the best source for parts. There are options? The main thing is what ever engine you find it must have a full tread crankshaft. Then manifold is what you need. If you find a different brand engine then you have to find a manifold for that engine. The kit came in two versions: Kit no engine and with kit a engine with pull start.

What brand body did you use? the original bodies are expensive and very thin.

 

[doutrnz]

@monstertruckier15: I see. Thanks for the clarification. I thought you were referring to the engine. You provided a lot of great information on options to use. I've already invested too much into restoring this engine so I'm going to keep those options as a last resort. I'm not at the point of giving up on it. I really appreciate your input though!!

 

[monstertruckier15]

If the carb is leaking that's not good. You can get some of the O-rings for it but the high speed needle 0-ring is gone. The backplate gasket is gone but you can use gasket sealer to fix that. The carb boot is another part that can't be replaced. The RFb engine was ok for a starter motor but the RG is better. Unless you stocked up on parts like me you truck will become a shelf queen.