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O320 start after sitting first AC motor

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Wildhair

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Bought my first AC boat this spring and it ran fine when I took it out. I took the motor off this summer to do some repairs on the hull that were much needed. So it hasn't been run since May/June. As with any project the repairs on the hull went from minor to major so just got it all back together this weekend.

Plus fixed a lot of wiring and quick fixes that someone had done over the years.

Anyway I wanted to know if there is anything I should do before starting it after it's been sitting for so long? Its a narrow deck O320

I did an oil and filter change and serviced the carb. Thanks in advance.
 
make sure it has clean fuel, oil and i would spin it over a few times before i hit the mags. other than that, i think you'll be fine
 
smokster said:
make sure it has clean fuel, oil and i would spin it over a few times before i hit the mags. other than that, i think you'll be fine
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Thanks for the advice. Yeah new oil, clean fuel since I just replaced the fuel tank. Just wanted to make sure I’m not missing something
 
So having some trouble getting it running now. It looks like i have spark on all plugs, but I replaced the plugs just to be sure. They are Autolite 386 with a .027" gap. I also cleaned the carb while I had it down and replaced the accelerator pump piston to clear up the flat spot in the throttle. The carb is an MA-4SPA. It ran well before I pulled it for repairs on the hull so I am a little stumped.

What are things to check next?
 
Drop that gap to 18. Are you getting gas out of the carburetor when you depress the pedal a few times?
 
Gary S said:
Drop that gap to 18. Are you getting gas out of the carburetor when you depress the pedal a few times?
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Turns out I had the mixture assembly not seated correctly into the bowl, as well as the butterfly was not fully closed so it was trying to start at about 1k rpm. The combination made it a hard start. I did drop the gap to 0.018" on the plugs at the same time. Cold starts no problem now.

Thanks for the help.
 
Boat had been running great until Sunday had a hard start and cylinder 2 never got hot. I checked the plugs and they were wet, so I replaced them and got it to fire and warm up but any throttle above an idle it would back fire through the carb. Eventually after it warmed up and ran it would throttle up with some backfiring and then cleaned up and would throttle up and hit 2700rpm at full throttle on the trailer. Let it cool and went through the same issue. I thought maybe I had a carbon up valve running it too rich and it cleaned up. Maybe run some seafoam through it?

Things to check?
 
Might be a sticky valve, marvel mystery or seafoam in the gas wouldn’t hurt. Seafoam the oil too. Could be a stuck lifter. You can pull the lifters without pulling the jugs. Probably worth pulling them all, cleaning/checking them and reset valve lash all around after you run a tank of cleaner through her. Since she has been sitting for a while, no telling what crap is in the oil. I’d change that when doing valve lash.
 
Slidin Gator said:
Might be a sticky valve, marvel mystery or seafoam in the gas wouldn’t hurt. Seafoam the oil too. Could be a stuck lifter. You can pull the lifters without pulling the jugs. Probably worth pulling them all, cleaning/checking them and reset valve lash all around after you run a tank of cleaner through her. Since she has been sitting for a while, no telling what crap is in the oil. I’d change that when doing valve lash.
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Thanks Slidin. This was the 4th time I ran it after getting the boat back together and it ran great the 3 times before. We ran about and hour or two each trip burning around 10gallons of gas. I also put a new fuel tank in so it was all new fuel.

But this was the first time it was really cold (below freezing), though the afternoon ride back same issue and it was 50 out. I did an oil change right before I put the engine and stand back on the boat. But I'll seafoam the gas and oil and run this tank of fuel out then check the lifters. Thanks for the help.
 
Slidin Gator said:
Here is a link to one of my threads on the page covering lifters. Do not use a magnet when pulling the lifters, see the thread.

Make sure to check the stupid stuff, intake tube leaks, both mags/plugs/wires failing on the same cylinder etc.
Oil Leaks Are Normal - Curtiss Jenny & A Lycoming Angle Valve (AV) IO-540 Tear Down
Oil Leaks Are Normal - Curtiss Jenny & A Lycoming Angle Valve (AV) IO-540 Tear Down
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Thanks! That's a very informative thread. I am suspect of my intake tubes leaking, they look old and hard I be there is a crack leaking. It looks like I did have both plugs fail on cyl 3. Hopefully can check the intake leaks tomorrow when I have some daylight, these short winter days make it tough to work on anything.
 
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