Re: Yamaha 130 rebuild questions
I will try a shot at this and see if i am on the same page as Rodbolt.<br /><br />"What part do I need checked at an outboard shop?" I would say the block, to be sure the cylinder walls are okay and the crank case and intake and exhaust ports are not damaged.<br /><br />"Do I need to replace the piston that has the melted ring on it?" See what the outboard shop says. If the top of the piston is not hurt, it has not been bent out of shape, and the ring journals (seats) are okay, you may can reuse it.<br /><br />Boring siae & Horsepower??? I Don't know?? MAy Rod can answer that one.<br /><br />"Bottom bearing? Is this in the bottom of the crankcase?" Yes, this would be the bearing, also called a lower main bearing on the crank.<br /><br />"Recirc check valves? Huh?" I don't know on this either.<br /><br />"Replace fuel pump? why?" If you are doing a rebuild, the last thing you want to happen is a small part going out that you could have replaced and saved the headache. You can probably rebuild the fuel pump instead of replace it. I am not sure on the Yamaha.<br /><br />"Do the carbs. I'm assuming you mean overhaul the carbs? These were replaced two years ago." Yes, overhaul them. You said this disasted happened in August, it is not Dec and I assume the engine has not been cranked since. THe carbs are probably begining to gum up or have the fuel in them varnish. I good rebuild will ensure that they work properly and reduce the chance of running the rebuilt engine in a lean condition.<br /><br />"Replace pressure valve grommet t-stats.<br />Are these the thermostats that I pulled out of the cylinder head covers or are you talking about the thermoswitches?<br />Complete pump kit? Once again, huh?<br />Pump kit for what?" Yes, these are the thermostats that are pulled out of the head covers. Like any new engine application or rebuild, always replace the thermostats and the waterpump to prevent problems. THe Pump Kit is to rebuild the water pump. Again, this is a 10+ year old engine and may never have had a water pump rebuild or an impeller replacement. Doing the rebuild, the last thing you want to happen is an over heat on the sea-trail and ruin the rebuild work.<br /><br />Rod, I think I was on the same track as you, please confirm and I hope this helps.<br /><br />knightgang
. I would do all 4 pistons to the first overbore. replace the bottom bearing, replace the recirc check valves. replace the fuel pump and do the carbs. replace the pressure valve grommet t-stats and complete pump kit.<br /> good luck and keep posting
