Product Review Article...
A neat engine reversing kit by MHZ...ideal for twin counter-rotating engine setups in big boats!
MHZ have built a solid reputation supplying quality boats, engines and hardware. This is a new product in their impressive lineup of engine accessories. The engine reversing kit is a simple and effective way to convert a Zenoah engine to reverse rotation for a twin-engine counter-rotating application. Granted twin engine setups require large hulls and might not be for everyone out there, but it has become more common in the past years and if you want counter-rotating engines it can't get any simpler than this!
Traditionally reversing the rotation of an engine is not impossible, but it is a very complex task involving a considerable amount of machine work and engine timing modifications, in many cases beyond the capabilities of most model boat hobbyists. Another issue is often to try and match two engines to perform as close to identical as possible after all the modifications. MHZ have taken a much simpler approach to engine rotation reversing. They actually flip the engine around! That's right, this kit actually converts the flywheel end to the output end and mounts the new pull starter at the old output end. The crankshaft itself is still actually turning in the same direction as originally in respect to the engine, but the output is reversed in relation to the propeller! A very ingenious way to reverse rotation without actually changing ANYTHING inside the engine! It is therefore easy to have 2 matched engines...take two stock engines, reverse one with the MHZ kit, keep the other one stock and you now have two matched counter-rotating engines for your large scale project!
Below are step-by-step pictures of the conversion. I used a stock Zenoah engine and did the entire conversion in about 15 minutes.
Here are the parts included in the kit and some pictures of the instruction sheets supplied. The kit included a coil relocating bracket but I did not install it for this review.
As you can see, this kit is very easy to install. The parts are precision machined and everything goes together quite well. All the major parts in the kit we received were anodized. The screws are stainless steel.
As can be seen in the pictures above, the clutch output is an 8mm non tapered shaft. An adaptor will be required to allow for the flexcable installation.
The adaptors are available from MHZ: P/N m-1023/8 (collet) or m-1050/8 (square)
This is a must have kit for anyone wanting to build a twin counter-rotating engine boat! It can't get any easier and the engine can easily be converted back to normal operation at any time if desired.
This kit is a great deal considering that you get the reversing kit, a built-in high quality clutch and engine mounts all in one package! Install matching MHZ mounts and clutch on your second engine and you have a perfect pair for the ultimate large scale project! Definitely two thumbs up!
Price of kit as reviewed: $305.00 USD plus shipping (prices subject to change...confirm pricing with MHZ-USA)
MHZ Germany: http://www.mhz-engines.com/