Hey guys, finishing up the process of getting my father's (once his father's) QDL-18 Johnson 10hp rebuilt and ready to fire for the first time in 30+ years. Unfortunately there was gas left in the tank (old style pressurized 6 gallon 1956 or prior with hole in middle of diaphragm for fuel pump push rod) for maybe that long as well so you can imagine the horror. However, I had good luck/fortune and was able to clean it up quite successfully with some phosphoric acid and elbow grease. All the tank components have been thoroughly cleaned with new gaskets, double hose line, and diaphragm on the way delivered by Friday. All other parts are totally reusable (float is free, gauge works perfect, foot valve/screen are clear and allows water to pass, etc.) so I wanted to keep it as original as possible. When the tank was finished I went ahead and put a few ounces of Amsoil HP 2-stroke synthetic in there and taped it off to slosh it around and ensure that no flash rust appeared on the gray coating the acid left which I understood should have inhibited rust anyways but I wanted to be sure. When I told my friend this who just bought and rebuilt a 1954 Johonson 5.5hp, he was concerned and asked me if the oil was appropriate simply because it says injector oil on the front. I told him it had good reviews and has the TC-W3 designation and says 50:1 premix. With that being said, I wanted to ask anyone on here if that is a good way to go because I know the original formula called for 24:1 but have done a lot of research saying that newer oils are better and older motors can be run much leaner so I was aiming for like 32:1 maybe at first and then go from there. My thinking is that the motor has sat forever and probably needs a little extra oil to start off with for the lubrication and then I'd play around with it to see what it really likes as ease of starting, idling, smoke, excess oil on the water all come to mind. Any ideas or thoughts/suggestions or do/don'ts?
On a side note, the engine itself is immaculate with only a very little wear and tear on the paint in the obvious places. When we took the cover off it was basically dust free inside with absolutely no corrosion. We tested the lower unit pressure to 60lbs+ and it had no leaks and the gear lube has been replaced. The only noticeable damage was broken coils (the covers were all cracked and discolored which I understand to be common with those after many years) but I already have 2 new OMC ones to put on but still waiting for my own flywheel puller to get here which also comes Friday. We lightly sanded the points and those along with the condensers were spotless even though they may need replacing as I'll find out. The plugs are still in there from 30+ years ago and are really clean and they both throw a spark but only when in the top so I'm hoping it was just that coil for the bottom, but like I said, I'll find out. The plug wires are still rubbery and flexible with no cuts or anything. The carb looked pretty dang good too but has not been rebuilt or cleaned so we'll see. My father said when it last ran it was ran dry and stored. My buddy thinks it will fire right up so that is the hope as he's on his 4th rebuild in the past year or two. I also have a 1968 1.5hp Evinrude that is very clean (zero rust in its gas tank) with very few hours that is next inline along with replacing the wooden trim on his 14' aluminum Starcraft which the motors will once again join in tandem to hopefully hit the water come spring.
This is the oil I was going to use as my premix. Thanks a ton for any help, tips, etc.
On a side note, the engine itself is immaculate with only a very little wear and tear on the paint in the obvious places. When we took the cover off it was basically dust free inside with absolutely no corrosion. We tested the lower unit pressure to 60lbs+ and it had no leaks and the gear lube has been replaced. The only noticeable damage was broken coils (the covers were all cracked and discolored which I understand to be common with those after many years) but I already have 2 new OMC ones to put on but still waiting for my own flywheel puller to get here which also comes Friday. We lightly sanded the points and those along with the condensers were spotless even though they may need replacing as I'll find out. The plugs are still in there from 30+ years ago and are really clean and they both throw a spark but only when in the top so I'm hoping it was just that coil for the bottom, but like I said, I'll find out. The plug wires are still rubbery and flexible with no cuts or anything. The carb looked pretty dang good too but has not been rebuilt or cleaned so we'll see. My father said when it last ran it was ran dry and stored. My buddy thinks it will fire right up so that is the hope as he's on his 4th rebuild in the past year or two. I also have a 1968 1.5hp Evinrude that is very clean (zero rust in its gas tank) with very few hours that is next inline along with replacing the wooden trim on his 14' aluminum Starcraft which the motors will once again join in tandem to hopefully hit the water come spring.
