Mercury 90hp 4 stroke problems

Tailguner

Seaman
Joined
Aug 5, 2010
Messages
69
I recently purchased a 2005 sun tracker party barge and it has a mercury 90hp 4 stroke outboard on it serial# 1B103481 90 ELPT 4S with 8 pin harness. This is my first outboard so I have a lot of questions.

1. the valve shim appears to have gotten of place and nicked the side where it sits, is this an easy repair?
2. whats the best way to clean the carbs I have read that these motors have really small jets that clog easily?
3. the prior owner had the pontoon in a slip and the outboard is covered in gunk ? best way to clean this off ? I think the cowl and legs are plastic or fiberglass hard to tell.
4. whats the best service manual I can get so I can replace the head ? oem? seloc?
5. I'm a pretty good mechanic with cars (17 ASE's) but outboards are foreign to me thats why I always stuck to I/O.
6. if the motor is trashed what year mercury 4 strokes can i get that matches the 8 pin harness ? - I really dont want to have to re-rigg the pontoon with new throttle and steering cables and controls.
7. Is there a website that will tell me all the specs on this motor ie parts,maintenance etc cyl head.jpgoutboard.jpgleg.jpgleg2.jpg
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
The best service manual for your engine is the one that Mercury prepared. In other words, the OEM manual. That manual would also have the engine specs you are looking for as well as electrical diagrams.
 
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