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1986 Evinrude 4hp not starting.

M

meverett

Member
I have a 4hp Evinrude that has hardly been used since new.
I got it set up the other day to check it over but it will not start.
I have checked for a spark and its good on both cylinders.
I have checked compression and again good at 140-150psi.
I have stripped the carb and cleaned it, fresh fuel but it will not start.
I have also checked that the ht leads are on the correct cylinder as well.
Any ideas? Please.
 
Based on what you are saying the motor should run.------------What happens when you spray a little mixed fuel straight into the carburetor ??
 
Thanks Racerone,
Just tried that and still not firing up. Checked again for a spark, put new plugs in and still nothing.
I have stripped out the reed valves and they look like new. May try to source another carb to see if that works.
Thanks again,
 
If the motor does nothing when you put fuel in the carburetor throat, then likely it is not fuel / carburetor related.------Try reversing plug wires !-------Inspect flywheel key as well.
 
I tried swapping the plug wires around which didn't work also had the flywheel off and didnt notice anything wrong with the key so the spark should be timed right.
Thanks again,
 
One last stab at helping on this motor.---------Good spark ?------------Compression and a clean carburetor then the motor should run.-------------Does spark jump a gap of 1/4" with a snap that you can hear ??-------Or was spark checked by laying the plugs on the block.
 
That motor has the universal magneto ( points / coils / condensers ) and I have never seen one that would jump 1/2 "---------1/4" gap indicates strong ignition on that model.
 
Thanks for all the help. I did check with squirting some fuel mix straight into the cylinders and try to start it but still nothing. Does this mean a strip down and replace cranks seals? Not a major problem as it is easy to strip. I will check that it will spark 1/4" gap first as I just checked with the plug earthed on the block.
Many thanks again,
 
Checking with plugs on the block is ----NOT A GOOD TEST----------It tells you there is some spark at atmosheric pressure.---------It takes more voltage to jump that gap when air is present and compressed to say 70 PSI in the cylinder.--------No need to think about tearing that motor apart just yet !--------------So do a proper spark test first.
 
Thanks to everyone helping me.
Here goes, I have set the points to 0.020 and the plugs to 0.030 then tried it and nothing. Tried the spark test at 1/2" and no spark, tried it at 1/4" and it does spark but not on every pull, checked the connections and still the same not on every pull.
 
Perhaps the points need a good ,and I mean good cleaning.-----------No dirt / oil of any kind left on the points affter cleaning.
 
Apparently in post # 1 it says that the motor has hardly been used.-----------Cleaning the points would be step #1, after that more trouble shooting can be done if needed.
 
Here goes,
I have stripped the coils, points and condensors, given them a good clean paying attention to the points. Put it all back together and reinserted the HT leads into the coils. Set the points to 0.020 and done a spark test, got a spark to jump 1/4" on both leads and even got the spark to jump 1/2" at times.
Tried to fire it up again and still nothing.
I think I will leave this one for another day and come back to it.
Many, many thanks for all your help.
 
Are you saying this engine can have 140-150 psi compression when new?? I know this is an older thread but I'm having a similar problem.I am pulling 75-80 psi and was told by members in this group that 75-80 psi is good.Does ANYONE know what factory spec is??
 
lakewind said:
Are you saying this engine can have 140-150 psi compression when new?? I know this is an older thread but I'm having a similar problem.I am pulling 75-80 psi and was told by members in this group that 75-80 psi is good.Does ANYONE know what factory spec is??
Click to expand...

Close to 100 is okay...... 140/150 is impossible!
 
Whoops.... Just noticed that date of 2012 pop up.

How in the hell did that sneak in here?.... Time for a beer anyway! :)
 
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