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77 Stinger Running lean

Timguy, ya... i am still at it. But i am getting close to the end. Have my fingers crossed. Need to set up a tech. If i am gona be beaten by it, i will tow it across the river and meet you in person :).
 
Flyingscott, thanks for the link. I went through the same procedure last night. Accept the 4 degree thing. My engine does not have a fast start . They use the same technique on some airplane engines. retarding the spark for an easy and safe handproping starts. The timing advances after the engine reaches 400 rpm threshold. So i set it right on the money. Will be checking it tonight after work.
 
Still trying to rig up a tach. But something interesting happened. ran a tank of fuel with SeaFoam in it. Smoked my house up but.... the compression went from 112 to 125 -127psi. Does this mean the engine sat for years? and rings are breaking lose?
 
Maybe maybe not you will have to run it for a while to find out for sure. Use engine tune from BRP /Ring free from Yamaha or Engine tune from Mercury to clean carbon out of the motor. Those products work 10x better than seafoam.
 
One more issue. I am using the laser gun to check the temp. Is it wrong?. I see that operating temp should be around 160 degrees. Mine is half of that, Is thermostat suck open or missing?
 
After a short family break i am happy to report on my progress. I finally took the boat to the lake. It started in the water as expected. Idle is almost satisfactory. I still do not have a tach. It bogs down if throttle advanced sharply. If i advance slow i can get on plane pretty quick. At 3/4 throttle is moves nicely. From 3/4 to 4/4 if i punch it - it throws me in the back of the seat. Just the damn transition isn't there.
If i bump the choke for a split moment it momentarily bogs down and the recovers quickly and accelerates nicely. But here is something else i found. Flyingscott- you were almost correct. I have ordered a thermostat kit and it came in today. Popped the cover and ..... there was a big HOLE - no thermostat. Whoever put the engine together used the red permatex instead of a gasket.

Now... that is the reason the engine never got to temp. I understand that in 2 cycle the engine temp is much more critical then in a 4 cycle. Cold engine temp may cause a lean condition ( my thinking). How would the engine behave if the thermostat is missing?
Do i have one problem or still possibly two?.

Thanks guys for all you help. It still a bit sick... but it aint limpin no more :)
 
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One more thing happen. No i have two boats. Traded my remote control airplanes for a 1084 Bayliner Capri with AQ125 and 270 in it. I am just getting ready for all the criticism in another forum :)
 
maugli said:
After a short family break i am happy to report on my progress. I finally took the boat to the lake. It started in the water as expected. Idle is almost satisfactory. I still do not have a tach. It bogs down if throttle advanced sharply. If i advance slow i can get on plane pretty quick. At 3/4 throttle is moves nicely. From 3/4 to 4/4 if i punch it - it throws me in the back of the seat. Just the damn transition isn't there.
If i bump the choke for a split moment it momentarily bogs down and the recovers quickly and accelerates nicely. But here is something else i found. Flyingscott- you were almost correct. I have ordered a thermostat kit and it came in today. Popped the cover and ..... there was a big HOLE - no thermostat. Whoever put the engine together used the red permatex instead of a gasket.

Now... that is the reason the engine never got to temp. I understand that in 2 cycle the engine temp is much more critical then in a 4 cycle. Cold engine temp may cause a lean condition ( my thinking). How would the engine behave if the thermostat is missing?
Do i have one problem or still possibly two?.

Thanks guys for all you help. It still a bit sick... but it aint limpin no more :)
Click to expand...
Do not run without a thermostat the engine will not come up to normal temp and is hard on the pistons, rings and cylinder walls. Put your hand on the head after five minutes it should get hot enough you want to pull your hand away but do not have to for a slow count to six.
 
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