Test tank question for johnson 100hp

[RobSS]

Howdy all
I own a 1972 Johnson 100hp.
Here is what i would like to do... is it going to work?
Using a large slightly modified trash can and my muffs run my engine at idle in the trash can to prevent over reving and on my muffs to ensure engine remains cool. The problem i have been having is that i get the carbs adjusted on the muffs alone but once i get them in the water with any sort of load they are mis-adjusted. I realize it wont be dead on river conditions but my engine will have some load and back pressure on the exhaust system to get them dialed in more ball park. I would appreciate any input anyone may have on this. If it is a horrible idea please let me know.
Thanks.

 

[Boss Hawg]

Re: Test tank question for johnson 100hp

If i'm understanding the situation corectly you have you lower in a barrel AND on muffs?
If so leave off the muffs & just use the barrel-
That will simulate the motor actually being in the water - river- lake or whatever
The idle settings will be the same, motor won't know what type body of water its in-

 

[Bifflefan]

Re: Test tank question for johnson 100hp

I use a cut out 55 gal plastic drum, no muffs, and no prop for my 85 HP. Then just run the hose in it also to replace the spillage.

 

[kenmyfam]

Re: Test tank question for johnson 100hp

Personally I would fine tune it on the lake.

 

[tashasdaddy]

Re: Test tank question for johnson 100hp

set your idle speed at around 1000 on muffs, then put it in the real water, and fine tune it. must be in gear, and in the water to fine tune.

 

[RobSS]

Re: Test tank question for johnson 100hp

Thank you all for the help.