CapeTown73
Well-Known Member
- Joined
- Mar 14, 2007
- Messages
- 180
Hi Guys,
I would appreciate your advice with the following problem.
Since I started racing 7.5cc OB tunnels in 2006, I first used Rossi powerheads and when the Nova OB powerhead arrived about 3 years ago I switched and have had nothing but great performance from the Nova. However, without going into the details, I managed to damage the engine and don’t currently have the required spare parts to fix it. Our final club race day for the current season is in a few weeks. We then have a two and a half month winter break during which time I plan to rebuild the Nova.
So for the first time in my life I’m preparing/rebuilding a used 7.5cc Redhead K&B that I bought last year but have never run. As the old piston/sleeve is way past it’s sell-by-date, I’ve decided to install a new piston/sleeve/conrod assembly that Joe Monohan kindly obtained for me but here’s the problem. After installing the new assembly and bolting down the cooling head (without the glow-plug), I tried to ratate the crank by turning the flywheel by hand and it is absolutely impossible to turn the crank further than the position as shown in the two attached photos.
Please tell me how to ‘lap’ the piston into the liner manually as I’m concerned that if I tried to start the engine with my electric starter, I may damage the conrod or it’s bushings.
Joe mentioned that he would be away from home for the next two weeks so I’m not sure if he will see this message which is the only reason why I’m asking the other K&B specialists here on our forum. Thanks up front for any help.
I would appreciate your advice with the following problem.
Since I started racing 7.5cc OB tunnels in 2006, I first used Rossi powerheads and when the Nova OB powerhead arrived about 3 years ago I switched and have had nothing but great performance from the Nova. However, without going into the details, I managed to damage the engine and don’t currently have the required spare parts to fix it. Our final club race day for the current season is in a few weeks. We then have a two and a half month winter break during which time I plan to rebuild the Nova.
So for the first time in my life I’m preparing/rebuilding a used 7.5cc Redhead K&B that I bought last year but have never run. As the old piston/sleeve is way past it’s sell-by-date, I’ve decided to install a new piston/sleeve/conrod assembly that Joe Monohan kindly obtained for me but here’s the problem. After installing the new assembly and bolting down the cooling head (without the glow-plug), I tried to ratate the crank by turning the flywheel by hand and it is absolutely impossible to turn the crank further than the position as shown in the two attached photos.
Please tell me how to ‘lap’ the piston into the liner manually as I’m concerned that if I tried to start the engine with my electric starter, I may damage the conrod or it’s bushings.
Joe mentioned that he would be away from home for the next two weeks so I’m not sure if he will see this message which is the only reason why I’m asking the other K&B specialists here on our forum. Thanks up front for any help.