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TRIM and MPH TACH

carlnap

Contributing Member
"I put my boat in the other da

"I put my boat in the other day after having my lower unit put back. Everything seemed to be okay except. When I put my drive all the way down the tach read only half way down. Also my MPH tach intermittenly worked last year and this year,nothing?? Any suggestions??"
 
Carl:
"When I put my dr


Carl:
"When I put my drive all the way down the tach read only half way down." Are you talking about the TRIM gauge? I don't believe that the needle should point straight down with the drive in the run position; maybe to the 5 O'Clock position. Did the mech. move the trim position sender? That will send the gauge a wrong position reading. See the manual for the simple adjustment.

"my MPH tach intermittenly worked last year". Are you talking about the speedometer or engine tachometer? The tach is the engine RPM meter while the speedometer is the boat's speed. It is controlled by a PITOT TUBE at the rear of the boat and has a rubber hose connected to it. Water pressure forces air in the hose to move the gauge. Note: some models have the pickup for the gauge built into the OD. Look for a kink in the rubber hose or dirt in the pickup tube at the stern. A LITTLE shot of compressed air will tell you if it is working. I bet the hose is kinked or split somewhere.

Guy
 
"Carl: Turn the stern drive h

"Carl: Turn the stern drive hard to port (LEFT) in the full down trim position. The trim sender is on the starboard (RIGHT) side of the OD. Loosen (just a little)the two adjusting screws securing the trim position sender. Turn on the ignition key to the RUN position. Rotate the housing in the required direction until the gauge reads in the bottom limit. Tighten the screws and recheck the gauge while running the drive up/down. If correct, turn off key.
Guy"
 
"If the drive was removed, I w

"If the drive was removed, I wouldn't be surprised to see that the speedo hose wasn't re-installed. How it attaches depends on what year the drive was made. Some were just slipped onto a fitting and use a zip-tie to hold it on and some have a white nylon piece that you rotate a quarter turn and slip on, then rotate back to lock it in place. If you use compressed air on the speedo, don't set the regulator to more than about 30 PSI. You can damage the gauge with high pressure. Better to look for a loose, thin black hose and leave it off when you use compressed air. If you want to test the gauge, blow air into the hose without having the blow gun directly attached (from about 3", or so)."
 
Thanks again guys both problem

Thanks again guys both problems are fixed and the boat is finally ready to be put in the water.Thanks Carl!!!
 
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