Re: 2002 lpx 5.0 merc
The 3 problems will not be related.
The speedometer is simply a pressure transducer. Water entering the speedometer pickup compresses air in the rubber hose going to the speedometer. The air pressure causes the speedometer needle to deflect. Increased pressure means increased speedometer needle deflection. No speedometer needle deflection means no pressure is getting up to the speedometer.
The speedometer pickup is a small hole in the leading edge of the outdrive. Debris will often clog the hole and the speedometer will no longer work. Another common cause of the problem is the rubber hose for the speedometer is often disconnected when the outdrive is serviced and forgotten to be reconnected. The connection for the rubber hose is also on the front edge of the outdrive near the anti-ventilation plate and connects to a small plastic fitting. If the pickup hole on the front of the outdrive is clogged, you can use a fairly long, small diameter drill bit to clean the debris out of the hole by hand. DO NOT use a drill or anything like to clean out the debris. DONOT use compressed air and blow towards the speedometer.
Trim gauge - does it move at all? or is the trim indication irratic or totally dead as the outdrive is moved? A common source of an irratic trim indication problem or totally dead indication is a defective trim sending unit (located on the starboard side of the outdrive gimbal ring) or a broken wire to the trim sending unit. If the trim sending unit "puck" has previously been removed from the gimbal ring, it is possible that it was not reinstalled properly. A smooth but incorrect trim indication is a simple adjustment. The trim sending unit "puck" is held onto the gimbal ring by 2 screws, run the outdrive fully down, loosen the secrews, rotate the puck until the trim gauge indicated a full down indication and tighten the 2 screws securing the trim sending unit. Trim gauge troubleshooting can be found at
http://www.faria-instruments.com/downloads.php under Misc. Instructions. Unlikely, but not unheard of that the gauge is the problem.
Trim not coming up - Do you have a transom trim switch? If so, does the outdrive raise using the transom trim switch? Any click sound heard when trying to run the outdrive up? There are 2 relays on the trim hydraulic unit, swap the relays around to see if the outdrive will then move up but not down...meaning the trim up relay is defective. Another possibility is a defective trim switch on the throttle control handle or a broken wire between the trim switch on the throttle control handle and the trim hydraulic unit. A volt meter would be useful to locate the problem. Wiring schematics for the trim circuit can be found on the internet and downloaded.
