1990 20 hp Mercury

Looking for some advise from members with experience with this vintage of Merc 2 stroke. I found a motor on CL. It’s in mint condition, very low hrs. I’m more familiar with the OMC design. Is there any thing I need to look out for in these old Merc’s? How does the tiller-shift mechanism hold up over the long haul? Thanks


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I've had good luck with the old Mercs with no problems from the tiller-shift mechanism. The electronics can be hard to trouble shoot if not familiar with them.

I've got one of those from a bit earlier in their model years.

Great motors. I took my tiller off and converted it to remote, so I can't comment on the linkage durability but I've never encountered anyone having issues with it that stand out in my mind.

The only difference between the 20 and the 25 is the carb, which is an easy part to source and a quick swap even by inexperienced hands, if you're that type. You can get a 25hp motor (assuming pull-start only) weighing in at only 115 lbs. which is at the top end of what I'd consider portable for me.

Original owner of an '88. Replaced the ignition switchbox (around '96) & the propshaft (in '13) when it had worn just enough that the unit would not hold pressure/vacuum. Spun the original prop in '17. Otherwise, it has been bulletproof. No issues w/the tiller/shift mechanism whatsoever.

onthewater102 said:

I've got one of those from a bit earlier in their model years.

Great motors. I took my tiller off and converted it to remote, so I can't comment on the linkage durability but I've never encountered anyone having issues with it that stand out in my mind.

The only difference between the 20 and the 25 is the carb, which is an easy part to source and a quick swap even by inexperienced hands, if you're that type. You can get a 25hp motor (assuming pull-start only) weighing in at only 115 lbs. which is at the top end of what I'd consider portable for me.

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That's interesting. I'm not the OP but have been on the hunt for a 25hp since our local restrictions went from 10hp to 25hp. Saw a 20 hp merc of similar year someone was wanting to trade for a 9.9hp, which I have. I may look into that after I research and see what the cost of a used 25hp carb is.

About $100 +/- depending on the source.

One on ebay now for that:
https://www.ebay.com/itm/25-HP-Sea-Pro-Carburator-1390-8889T22/192664539904?hash=item2cdbb39300:g:qzEAAOSwKEhbo~Jv:sc:FedExHomeDelivery!06757!US!-1:rk:17f:0