587 overheating

[jbusam115]

I posted before in march of 2021. Put a white 587 in a Jon boat . Lot of custom metal work, fabrication, engineering, welding, etc… long story short , had 2 hours of fun . Blew it up . Rings seized , scored front cylinder, ruined piston. Rotary gear gave up life …poor thing was running on borrowed time and I never knew it till it was too late . anyways . Got a new yellow 587. Rebuilt top to bottom. Never been run since rebuild.Swapped it in. Fired right up . For my application I converted it to single carb from my white 587. My issue I’m having is I don’t think my water lines are correct. I can’t for the life of my remember everything but I was sure I routed everything correct . They are different from my white 587. Took it out today. Got hot. Switched some lines around and got water flow finally . Did some jerry rigging . Engine cooled off . Could keep hand rested on it , then on the way back to the trailer . I could smell burning paint . The muffler can was smoking hot . The pipe was also very hot to touch and the top of the engine was warmer than I think it should be . I know it’s different than in a ski but the lines should still all be the same . I can post pictures and if anyone could tell me if I’m wrong or missed anything I’d much appreciate. The first was a reference pic from in the ski ( I might add this motor was not originally in this ski. Someone took a white out and put a yellow in and I found a few things they did wrong ) everything else is what I did to get water flow on the river today

 

[POPPS]

You can just find the manual for that motor for the correct hose routing,,,initially,,,seems that they are reversed,,,
When you run water through it is the pisser working,,,It is also possible that the drain lines are plugged,,,check that they are clear,,,had one once where the line was plugged zebra muscles…also…is the pump properly secured to the transom,,,if it is not,,,you will not get proper water flow to the cylinders,,,also,,,check that all water injection fittings are clear…

 

[mikidymac]

You are also going to be lean without the air box if you didn’t change the jetting and pop-off.

Pretty much everything is different between the white and yellow engines so water flow even though the pipe is going to be different.