2 questions from your newest noob. Tilt pin, Tachometer

[BassAssassin]

Howdy everyone,<br />i would like to start of by saying that this is a great site, and i have been coming here reading on all of my problems thus far. everyone gives great info and helps out a bunch. <br />Ok here is the skinny. i bought a 1978 monarch 18' bass boat about a year ago. i have been spending all my time and extra money refurbishing it. she is powered by a mercury 70hp motor, 1983 from what i can tell from previous posts (i have the serial but not on me right now). <br />My first question is about the tilt pin;<br />i know that the motor has to be enguaged for the tilt pin to lock(mainly reverse some forward too), but mine doesn't engage. i read that the ???? might need to be replaced in a previous post. when i tinkered with it a bit it'll move when put into reverse but just a little, nothing substantial. any thoughts would help.<br />my second question has to do with the tachometer. ifrom my readins i know that the brown wire is the "S" from my mercontrol and i have it all hooked up BUT it doesnt even move when i start the engine(i also heve it set at 6 for the poles). although i have not put the engine into gear. does it have to be in gear in oreder to get a reading? that would be stupid but hey you never know. and it might be the wrong type of tach too from what i have read.<br />well thanks for all your thoughts and help im positive you will hear from me again.

 

[WillyBWright]

Re: 2 questions from your newest noob. Tilt pin, Tachometer

Welcome to iboats.<br /><br />There is a cam on the shift shaft coming out of the gearcase. The originals were plastic and wore out. Replacements are metal. You have to drop the gearcase to replace it. That would be a good time to service the water pump. The tilt lock should engage in Neutral and Reverse. It releases in Forward.<br /><br />I believe the older versions with amplied battery ignition used a brown wire off the amp for the tach signal. Those have a distributor. On an ADI version (switchbox + 3 coils) it should be gray. The motor end attaches to one of the yellow leads on the rectifier. Find what color the wire is there and that's what color it should be at the gauge end. Merc has changed their wiring colors a few times, so it's possible for the remote wiring to not quite match the motor wiring. If all is connected well, then the likely cause is a blown rectifier. The tachometer reads off the alternator on an outboard. Seems like a strange place to get the signal from, but on an outboard the alternator is crankshaft driven making it quite accurate. If the rectifier blows, then the alternator doesn't alternate or send a signal. Tach operation has no connection to shifting. I believe the tachs are different for the different kinds of ignition systems as well, so a nonworking tach might mean it's the wrong tach. You mention a 6-poles setting which should mean it's the right tach for a distributorless model.

 

[BassAssassin]

Re: 2 questions from your newest noob. Tilt pin, Tachometer

Ya, thats what i thought about the tilt pin. didnt know that the OEM ones were plastic though thats sure a bonehead way to save money. that piece takes a beating whenever you are moving the throttle. just so i know, how often does the water pump need to be serviced? and the impeller too? i have to work on the boat on monday hopefully so i can take her out tuesday. i really appreciate all the help WBW. you gave me a bunch of good info already.

 

[WillyBWright]

Re: 2 questions from your newest noob. Tilt pin, Tachometer

The manufacturers advise annual water pump service. In most cases, 3 years isn't impractical. 5 years and you're pushing your luck. Naturally if the pump is weak, then it doesn't matter how much time is on it, it just needs to be replaced. In most cases, a water pump rebuild only requires an impeller and related gasket(s). Typically, unless you know the impeller is new and in good condition, replacing it is automatic anytime the gearcase comes off. You're in there anyhow.

 

[BassAssassin]

Re: 2 questions from your newest noob. Tilt pin, Tachometer

ya i have been told that this pump has about 1.5 years on it so its due. better safe than sorry. i need to order a few parts anyhow might as well order that kit. thanks a bunch for your help u have been gtrreat