Logo
FULL SITE MENU

86 90hp Mariner seized up

J

jbeb

New member
I am sure I will get a nice lecture over this one. I recently aquired a 16ft Charger with a nice trailer and a 90 HP Mariner. The boat has sat outside, near the lake, possibly sometimes partially in the water since 2003. I retrieved the boat and got it home. The power trim works perfectly but the motor is seized up. When I pulled the plugs they are ALL rusty. I tried spraying wd-40 into the spark plug holes. It is frozen solid. My neighbor and I used a breaker bar on the fly wheel nut....gently....but with enough umph to break it loose if it were going to be that easy. I have read all kinds of ideas and the main consensus I see is that the motor is toast even if I were able to get it freed up. I would appreciate any advice or possibly even confirmation to scrap it or keep trying. We are both mechanically inclined, the neighbor more-so than I, but neither of us have alot of experience with a 2-stroke outboard. When I got this boat the guy also had an 80's model Sylvan pontoon with a 28 hp Evinrude. The difference I think is that the Evinrude was not trimmed up. I put fuel and power to it and had it running within 10 minutes. Not so fortunate with the Mariner. From the looks of the boat the rear has been partially submerged at one time or another from the way it was sitting on the shore. I am guessing that water has sat in the motor.....unfortunately. Thank you very much for any thoughts, opinions and ideas.

John
 
Likely water on the precision internal parts.-----Bearings / crank / rods are likely scrap.---------Replacement parts can be found on E-bay for reasonable dollars.--------------Motor must come apart !
 
I really like Merc's 90 horse 2 stroke models - probably the most "successful" motor of all time (if you look simply at gross sales). You can totally rebuild this for about $1500 (if you don't count your labour - I did one two summers back so my price will be close).

So for 1.5K this is what you get -

Three cylinders bored or honed (50 to 100 bucks a hole at your local machine shop) - $150 to $300 (so shop around)

A "rebuild" kit - pistons, rings, rod bearings and gaskets ($500) or add main brngs, crank seals and rod bolts ($625) - if the rods are shot you can add about another $250 for the "total kit".

3 carb kits (@37 bucks a piece) = $111

Fuel pump kit ($13.50)

Water pump kit (the whole thing - new plate, gaskets, seals, impeller etc) $117

Maybe a lower unit seal kit ($70)

and a couple odds/ends (sparkplugs, gear oil etc)

If any ignition components are shot you could drop maybe a couple more hundred (coils about 45 bucks each, switchbox 200, stator or trigger under $150 each).

BUT, in the end you get a "like new" motor that should easily last another 20 years.

Compare that to the cost of a reman powerhead (about 3 grand and you still need the carbs/ignition etc from your existing motor) or a new 90 horse $7300 (discount price for either an Optimax or an EFI 4 stroke).

So I agree - definately a rebuildable motor and definately worth it unless there is a hole in the block - unless of course you have 10K just falling out of your wallet and you want a shiny new motor hangin on the back :)
 
Both 90 hp Mariners--3 and 6 cylinders--are "in-lines"! Think about it.

I would not assume the bearings are junk before getting her unstuck and running it--you might luck out. Getting her to turn over can be a pain, but time is on your side. You want to turn the motor carbs down (all the way down) then spray penetrating oil (not WD-40) into the holes for several days; then let it work. Give her a shot of penetraing oil every time you get near her.

I've unstuck a few that way, but it takes time and patience.

jeff
 
Back
Top