20hp merc ran fine, now won't crank

Zacharay55

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Aug 26, 2014
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27
I have 70's or 80's model 20hp mercury 2 stroke. I replaced the water pump and it ran fine, took it out to the river and it ran good the whole time I was out. It say r about 3 weeks, took it back and and it's not cranking. Carb is clean. Got good gas. It has a spark. It appears to be in time, i don't know where to go from here??
 

Fun Times

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Why do you may two posts for same problem???
It's not the OP's fault for having two or more topics about the same problem within the same sub-forum. The problem lies with the new forum software producing duplicate posts or topics. We're doing our best to keep the duplicates deleted to help lower the confusion until the problem gets solved internally. Sometimes some will get missed or overlooked for awhile. Thanks for your patience and understanding in advance.:)
 
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Zacharay55

Cadet
Joined
Aug 26, 2014
Messages
27
Why do you may two posts for same problem???
The motor turns over. It Is not starting. If it wouldn't turn over, it would have no spark. Normally when I pull started it it cranked up in the 2nd or 3rd pull and now I pull and pull and it won't hit a lick. It ran perfect. I didn't run it for about three weeks and when I took it out it just won't start up, took it home, took the carb off, bowl is clean an free, jets are clean, wiring is good, spark plugs are good, I don't know what else to check.
 

enginepower

Petty Officer 1st Class
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Jul 5, 2014
Messages
260
Do a compression check. Are plugs wet with fuel when you pulled them? Could be flooding and causing plugs to foul if so. Do you have enough spark to jump about a 1/2 inch gap? Weak spark could cause a no start.
 

Zacharay55

Cadet
Joined
Aug 26, 2014
Messages
27
Do a compression check. Are plugs wet with fuel when you pulled them? Could be flooding and causing plugs to foul if so. Do you have enough spark to jump about a 1/2 inch gap? Weak spark could cause a no start.
I have great compression, and spark plugs aren't wet.. Idk about how strong the spark is though..
 
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