1959 35 hp evinrude lark

Johnson110

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Dec 31, 2003
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Hi, This engine has spark compression seems ok , pumping primer bulb gets hard it will not fire, I took off carb and opened up the bottom no gunk looks clean, Anybody now these motors for some insight, Thanks
 

fhhuber

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Squirt a small amount of fuel mix in directly through the carb butterfly. See if it will pop a few times.
If it does then you have verified a carb issue.
If not then inadequate compression or inadequate spark or bad spark timing.

You CAN have visible spark with a bad plug.

Plenty of ways the carb could still be an issue without gunk in the bowl.
Quick, easy test.
 

F_R

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Have you checked the coils? Unless they have already been replaced, you can almost bet the farm that they are junk (cracked). Yeah, yeah, I know you said it has spark. But the coils are the Great Deceiver. It will have spark but not run. Nearly everybody tears into the carburetor before they discover the real reason it won't run.
 

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Johnson110

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Dec 31, 2003
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Yes I will check out the coils and check out the plugs i did squirt so ether in the cylinder, i know big no-no, just wanted to see if she would kick over, this engine also has the pressure relief on it, Thank you for the response I really appreciate it !
 

F_R

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Unless it was you, somebody has already been into that carburetor. It looks fine. How far open is the main needle? Should be around 5/8 turn, no more than 3/4. I still don't believe the trouble is carburetor.
 

Johnson110

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Thanks, This is how i got the motor, the guy that i brought it off said his father is an old time mechanic that is why i got it ,anyhow i did check the coils no cracks looked new along with the point, you say " main needle" not sure what that is i did not change any settings also the plugs champion j6c look old, i will change them, the motor is all new to be but looks pretty clean for it's age, Thanks
 

fhhuber

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Ether is bad for 2-strokes a few reasons... one is there is no oil. If its not getting enough gas to fire then its also not getting enough oil.

Pump up the fuel to the carb, pull the plugs, choke it and spin the engine several revolutions. You should be able to smell gas at the plug holes.
(I like tests that cost essentially nothing)

A gasoline engine needs fuel-air mix, adequate compression and properly timed spark.

Easiest to diagnose are compression and fuel.
Squirting fuel in, bypassing the carb, making it pop over (or not helping) proves (disproves) a fuel issue.
Compression gauge should be 110+ psi (more for an engine that isn't nearly worn out) Compression gauges are cheap.

If its spark then first you have to ensure you have spark at all, then if its timed correctly and powerful enough to ignite the fuel.

"Main needle" is the primary fuel metering needle valve in the carb.

There are little passages in any carb that can get plugged up. Annoying to clear some of them. I like fuel filters.
 

Johnson110

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Dec 31, 2003
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Ok, Then "main needle" still confused, the only adjustments that i know of are low speed an high speed needle adjustment, i removed the needle valve that was under the float checked it and out in back in there in no adjustment that i know of it, also good suggestion on pulling spark plugs and smell for gas , those plugs seemed bone dry to me!
 

Johnson110

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Dec 31, 2003
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I took plugs out champ j6c and put them in lawn mower they work, I dipped plugs in the 2 cylce gas and put them in engine still nothing, when I disconnected the gas line to motor gas shot out all over, I can I tell for sure that it is getting spark I try pulling the motor with plug attached to lead but it hard to see what the hell is gong on, checked the coils and point thru the access cover on flywheel they looked new. it seems like it should run carb very clean point clean not easy pulling ????????????????
 

racerone

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The ignition was designed to produce up to 28,000 volts.---Jumping the 0.030" gap on a sparkplug does not need that much.------So buy a proper spark tester or build something so you can force the ignition system to jump a gap of say 1/4" or more.-That is how you check for proper spark !
 

Johnson110

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Dec 31, 2003
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Ok, finally got someone to pull the recoil i grounded both plugs and the spark was intermittent one cylinder look white spark other looked more blue!
 
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