1986 Merc 60hp 3-cyl issue

andrewss

Seaman Apprentice
Joined
Oct 24, 2020
Messages
34
Pulled a family boat out today that hasnt run in a few years. It's been in a heated shop, under a cover, and was drained of fuel and fogged before sitting. Half the day was spent moving other **** out of the way that accumulated in front of it over the years lol.

Mixed up some fuel, threw the hose muffs on and God damn is fired up on the second crank and that 2 stroke sounded crisp.

No water out of the tell-tale though. I turned up the hose spigot and that had no effect. So I held the muffs on (is this bad?) which stopped them from leaking, still nothing out of the tell-tale. So I figured a blockage or bad impeller - but it was replaced before it ran last. I stood up and I swear there was water coming out from around the lower cylinder's spark plug. I immediately killed the engine and at that point. Given the time it was and the amount of crap I had to put back in the shop, I wheeled the boat back in and called the day a defeat.

So some history, it was last on the water in 2022. It ran great, punched up and got on plane, cruised on plane nice at 32kmhr and topped out at 52kmhr (32mph).. I have that info written down because I was comparing the 3 blade with a 4 blade prop. Oh and at that time the tell-tale pissed like it had been drinking Miller Lite all afternoon.

So without jump to worst case scenario, what are my next steps to diagnose this old beauty? Is it possible there's a seal failure in the LU and me forcing water through the muffs backfed water into the exhaust and then through the exhaust valve into the cylinder? And praying nothing bent.... Or is the head gasket the most probable?

Compression on all three cylinders in 2019 was lowish but even at 98-100-100. So once I figure the cooling system out, I'll rent a compression tester again

Any thoughts and prayers are welcome. I love this outboard so I have a pit in my stomach right now.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,411
Serial # is ?--If it is a 2 stroke ,there is no EXHAUST valve going to the cylinder.----And no head gasket either.
 

andrewss

Seaman Apprentice
Joined
Oct 24, 2020
Messages
34
SN 7014123
Or 7217467 is on the plaque on the motor, albeit very hard to read some of the digits. the other number I posted earlier was written in the manual from a previous owner who knows when

It is a 2 stroke
 

andrewss

Seaman Apprentice
Joined
Oct 24, 2020
Messages
34
No exhaust valves.----No cylinder head on that motor.

I think I'll pull the lower unit and see what's going on with the impeller. And see if I can blow low psi air through the tell-tale. If I can be confident that the cooling system is functioning I'll fire it up again and calmly see where water is or isn't coming from. In hind sight the spark plug was torqued in and shouldn't have allowed water to drop out, maybe the water line that runs near that plug was spray/dripping and in my haste to kill the engine I didn't pay close enough attention
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,588
Check tell tale hose first if it is clogged.
Not so uncommon if it has been running in salt water and if it has been sitting unused for some years.
Then check impeller, if it has been sitting unused the vanes get stiff and as they are bend in the impeller housing they got settled and not flex any more.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,634
Was there any water coming out of the Prop, when you were running it on the Muffs?
Water coming out from around the Spark Plug, means a bad Jacket Gasket, or more likely, in My Opinion, a warped Water Jacket Cover, which happens when the Motor gets too Hot
 
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