73 9.5 johnson smoking alot

[yamadirt426]

Picked up this motor. Everything runs and works good except it smokes blue pretty bad. I got the motor ,changed the leg oil ,changed the plugs,cleaned the carb, did comp test 63/73, then did a decarb with seafoam, (run only in a barrel so far) did another comp test now 64/70. Gonna do a run hopefully tonight or tomo but I have a feeling i'm gonna be doing piston and rings. Is the run on the water gonna make a diff ? I high idled seafoam with gas for about 15min and put in cylinders, then waited and then through carb and revved her on and off . She smoke white then back to her usual blue. Minimal at idle but fairly smokey at higher revs. She pumps water pretty good so the water run isn't gonna hurt and she actually runs good in the barrel just smokey. What do you brains think? I should have water run it before I posted but just waiting for the rain to stop which I think it just has .what else would make it smoke so much. I did notice the end of my rich/lean adjustment screw has a bad nick on the taper in the carb? I dont think that could be it though

 

[F_R]

Re: 73 9.5 johnson smoking alot

The nick on the needle will make it harder to adjust the idle mixture. Other than that, don't be freaking out about the smoke. Put it on a boat in the water and run the heck out of it to burn out all that stuff you dumped in it. Compression is a bit low, but if it starts and runs good go for it. You probably have some stuck rings may get better, may get worse....probably the latter.

It is supposed to smoke. But you notice it a lot more when it is confined in a barrel.

 

[yamadirt426]

Re: 73 9.5 johnson smoking alot

Ok. I'm gonna have to wait until tomo now to run it. I will and report back. Thanks FR

 

[yamadirt426]

Re: 73 9.5 johnson smoking alot

so I took the boat for a spin today after the decarb from yesterday. Well she fired up good with some smoke . Warmed her up and set of slowly went to turn on the power and nothing. My 68 6hp went better. Dropped my buddy of to lose a bit of weight and see if I could plane by myself. It was a no go. I knew this wasn't right. So when we were packing up the motor my buddy says "What about using the other spark plug". I says what other spark plug. What are you talking about, pulled the top off and only one lead is on. In my haste to try it out I didn't even care to check that out BEFORE the test ride. Idiot !!! But let me tell ya my disappointment turn to happy hollering as i twisted the throttle in a hurry. Motor has a great hole shot and goes to 33kph very quick. I didn't hardly notice any smoke on the water. This motor ran great with one cylinder on idle and everywhere just no power. Now she was flying. So much fun. Now two ?'s. 1 Is this the exact same as the evenrude 9.5 sport twin of the same era (73)? 2 At full rpm the water pump had what look like a good thick pee and at idle more of a spray pee. Seems right just wondering. Thanks again

 

[ezeke]

Re: 73 9.5 johnson smoking alot

When you get time, make sure that you have a good 143 degree thermostat in the engine; it will run cleaner - less smoke and less plug fouling. The 100% synthetic oils help too.

The Mercury 143 dgree thermostat MM-75692 works great, for about half the price of OEM.

The paint, decals and engine cover are different on the Evinrude, but they still fit. Everything else is the same in the respective year. Much is the same from 1968 through 1973.

 

[F_R]

Re: 73 9.5 johnson smoking alot

That is about the way the water spray should be.

 

[yamadirt426]

Re: 73 9.5 johnson smoking alot

I might as well change the thermostat then I guess. So I will order that this week thanks guys!!!

 

[iwombat]

Re: 73 9.5 johnson smoking alot

There's one difference. The '73 had a different reed cage/plate/whatever and a matching intake manifold. The newer reed cage had marginally better recirc capabilities. Seems like the 73 reeds work better for idle and mid though.