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Mercury 4.5 (45) Older Project Motor

F

FosTerH0ME

New member
I recently acquired an older mercury 4.5 hp 2 stroke outboard. I am working on getting this running and would like any advice someone might be able to offer.

I have found mud dobbers nest throughout the stator assembly under the flywheel. The insulation is cracking and wires are clearly visible through the wire insulation to the coil.

After cleaning up the majority of this mess, I still have no spark when I check and it will not even try to start. Recommendations? This motor sat for about 10 years in a barn.

Thanks for the help!!

https://lh3.googleusercontent.com/-...q-TCvjx-O2s/w1461-h822-no/20140612_202345.jpg
 
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Can't see what ignition system it has. What year is it?

Jeff

PS: You have the good fuel pump, and those are really nice little motors. The impeller needs to be changed before you do anything or...
 
fastjeff said:
Can't see what ignition system it has. What year is it?

Jeff

PS: You have the good fuel pump, and those are really nice little motors. The impeller needs to be changed before you do anything or...
Click to expand...


I'm not certain of the year. This was a craigslist find for very little money and the gentleman had next to no information. According to him the "bottom end was locked up." Patience, gear lube, and corrosion removal has that issue resolved and it rotates easy now when I pull the starter rope.

The serial number is 4110195. When I pull the starter it does not even attempt to crank. I am thinking that I do not have a spark. When I set it against the block and pull the rope I can not see a spark. I got a new plug just to eliminate that easy fix and will test again tonight.

I have a few more photos saved on my phone if they will help. I have worked on a number of motorcycles but have very limited outboard experience so feel free to state the obvious. I would rather feel stupid than waste my time and there is only one way to learn it!

Thanks again for the time and assistance!
 
Thunderbolt ignition
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Ugh! That's the infamous Phase Maker nightmare. The points need to be clean and gapped around .018, and the kill switch (IF it uses one) must be closed for it to run--the opposite of "normal".

Those are a royal pain to get sparking, but the singles (Vs. two cylinder ones) seem to work better.

Jeff
 
fastjeff said:
Ugh! That's the infamous Phase Maker nightmare. The points need to be clean and gapped around .018, and the kill switch (IF it uses one) must be closed for it to run--the opposite of "normal".

Those are a royal pain to get sparking, but the singles (Vs. two cylinder ones) seem to work better.

Jeff
Click to expand...

Thanks Jeff!!! I gapped the points and cleaned them but is there a simple way to bypass the kill switch for diagnostic purposes? I am missing part of it and I would like to test the motor and get it running while I wait on the few incoming replacement parts.
 
I am also working on one of these engine and didnt reallize that the kill switch should be closed to get spark thanks for the heads up ,, and fastjeff if you put a jumper wire from ground to the coil s negitive post that should work if it startes and you need to shut it down just pull off the wire if i am reading fosterhome correctly

and thanks for the info
 
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