RCU Forums - View Single Post - 1/4 scale Gas Tunnel boat ... what to build?
Old 01-15-2008, 02:56 AM
  #57  
Youngzrcboats
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Join Date: Nov 2007
Location: Cape TownWestern Province, SOUTH AFRICA
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Default RE: 1/4 scale Gas Tunnel boat ... what to build?

Hi WildGas
happy to see that you have your boat( it looks great) and motor, I hope Fred was able to supply you with the pipe, if not ,please let me know. Are you going to be at the World Tunnel race. We are really looking forward to meeting eveyone there. I have a laser cut top plate that will save you the bother of cutting that square mounting plate to the profile of the engine case as well as a coil mount plate that will accomodate a kill switch. We have found that the motor is very vulnerable to water been sucked in through the carb intake which causes serious dammage to the piston on the intake side. It seems to have a water jet effect which cutts the piston as well as a coling effect which changes the milicular structure and softens it ,causing it to distort. I ran a SIKK for about 2 hours without a suitable intake box (none whatsoever) and the piston eventually had so little compresion that the carb was spitting fuel instead of sucking it into the crankcase. The best senario is to creat a box with the intake at the top ,as high off the water as possible. Running any form of spunge filter definitely holds the top RPM back. Have a great build and if your transom is 96mm wide i have a laser cut and drilled Stainless steel transom that will help you convert that wedge transom angle to vertical as well as endure the visciuos vibration from the motor (Its likr a badly tuned Harley)
All the best
Dominic and Lisa-MArie