Hi,
I recently got a mako 228 with a pair of 120 nissans. I'm trying to get everything running with a minimum of expense because I don't want to sink money into a project without knowing just how bad everything is. I plan on eventually doing carbs, plugs, gear oil, control cables, electrical, etc. In the meantime I have both engines running off a portable fuel tank and keeping idle, which is good enough for me on that front. Next I am trying to sort out the trim on the starboard engine (port works fine) and cooling on both engines. One pees poorly and the other not at all.
The trim unit: the motor whirs, but it doesn't move up or down. I tried filling the reservoir, but no difference in operation. The service manual leads me to think I need to have the motor tilted up to pull the unit out, but the manual valve release might as well be welded shut. I removed one of the bolts holding the motor to the hydraulics in an attempt to get the pressure to release, but the bolt head sheared off with depressingly little torque. No pressure loss, and I'll just have to deal with that once the unit is out. My current plan is to drill out the center of the pressure release bolt as precisely as I can. However, the bottom pin attaching the trim unit to the bracket seems very stuck. After looking at a couple used ebay parts listings this seems like a common problem. An alternative seems to suspend the motor and take the mounting bracket apart from around the trim unit. Is there a trick to getting that lower pin out? I don't want to destroy the manual release valve if I will end up taking the bracket apart anyway.
Lower units: The bolts are very rusted out. A couple came out by hammering on sockets, but for the rest I think I will have to grind them flush and then pull them out using the threaded stubs exposed by removing the lower unit. I'm not too concerned about that, but who knows what I will find when I actually get to the impellers.
Also, I heard that these engines can be brought up to 140hp output by modifying the throttle stops and ignition timing. Is it worth doing this, or will I see problems with fuel economy and reliability?
I can't get the forum attachments to work so here is the imgur link: https://imgur.com/a/FoB1DSl
I recently got a mako 228 with a pair of 120 nissans. I'm trying to get everything running with a minimum of expense because I don't want to sink money into a project without knowing just how bad everything is. I plan on eventually doing carbs, plugs, gear oil, control cables, electrical, etc. In the meantime I have both engines running off a portable fuel tank and keeping idle, which is good enough for me on that front. Next I am trying to sort out the trim on the starboard engine (port works fine) and cooling on both engines. One pees poorly and the other not at all.
The trim unit: the motor whirs, but it doesn't move up or down. I tried filling the reservoir, but no difference in operation. The service manual leads me to think I need to have the motor tilted up to pull the unit out, but the manual valve release might as well be welded shut. I removed one of the bolts holding the motor to the hydraulics in an attempt to get the pressure to release, but the bolt head sheared off with depressingly little torque. No pressure loss, and I'll just have to deal with that once the unit is out. My current plan is to drill out the center of the pressure release bolt as precisely as I can. However, the bottom pin attaching the trim unit to the bracket seems very stuck. After looking at a couple used ebay parts listings this seems like a common problem. An alternative seems to suspend the motor and take the mounting bracket apart from around the trim unit. Is there a trick to getting that lower pin out? I don't want to destroy the manual release valve if I will end up taking the bracket apart anyway.
Lower units: The bolts are very rusted out. A couple came out by hammering on sockets, but for the rest I think I will have to grind them flush and then pull them out using the threaded stubs exposed by removing the lower unit. I'm not too concerned about that, but who knows what I will find when I actually get to the impellers.
Also, I heard that these engines can be brought up to 140hp output by modifying the throttle stops and ignition timing. Is it worth doing this, or will I see problems with fuel economy and reliability?
I can't get the forum attachments to work so here is the imgur link: https://imgur.com/a/FoB1DSl