79 70hp wont start

[brokenwrist]

The smoke issue seems to have solved itself as well. At idle its thin and kinds of wispy, but if I give it some fast idle, it gets a little heavier, but at this point I'm not gonna worry about it. If it's thin and wispy at idle, it isn't gonna bother me. I like the reliability and simplicity of working on these engines, but dang if they ain't finicky about everything, and I mean everything.

 

[brokenwrist]

It is also worth mentioning that, last time the carbs were off, I didn't look at the reeds. This time though I did, and they look brand new, no bends, they sit nicely. I know someone at some point before me was in the motor doing something.

 

[oldboat1]

might test the thermostat. If it's running cold, could account for some of the smoking. Running temp should be in the range of 130 - 140F (no hotter than 160).

 

[jerryjerry05]

The heat range for that thermo is 110d.
F528068 part#

 

[brokenwrist]

Just put a new thermostat in at the beginning of this whole debacle. New t-stat, gasket, and oring, also rebuilt the fuel pump, all 3 check valves replaced, new screen, gaskets and diaphragm.

 

[oldboat1]

t.stat and impeller replaced, sounds like (presumably 110 degree stat). Never hurts to check running temp -- good excuse for an IR tester, if you don't have one.

If running on muffs while testing, you are undoubtedly seeing more exhaust and getting more noise than if in the lake.

 

[brokenwrist]

I hate muffs, I always use a water tank. yep 110 degree t stat, impeller done last year when I put the new lower unit on.

 

[jerryjerry05]

Heat or temp gun

The heat gun became part of my tool kit a few years ago.
Can help solve problems without taking a bunch of stuff apart.