I've got a really nice '89 150hp on my POS- that has been great until this Spring when I began having starter problems- replaced the starter and solenoid(x2), cleaned up all the connections and replaced a weak battery. it keep doing the same thing- starts and runs fine for about an hour, then I turn the key and NOTHING happens (and the trim doesn't work anymore either) was originally diagnosed as solenoid issue. now the only way I can get back to the ramp is by jump-starting it over the solenoid with a pair of pliers....


any ideas as the what da' fu q is up with this thing??

Trim goes up when you jump with cables ?
Sounds like you got an alternator problem.
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Sounds like control box issue, bad wire to shifter, bad ground. Loosing juice at the key? Wiggle everything going into the shifter box and see of you can recreate the problem
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start with the ground at the starter to the block... check the crimp... if you see any sign of green replace it..also check the grounds that attach to the block at the starter solenoid... they have a propensity to loosen and corrode. Check the in line fuse holder at the starter solenoid... they provide power to the key switch and trim solonoids... if all that looks good and tests fine...it most likely is the key switch... they are a prime culprit for this type of grief....if I were a betting man..I'd look real close at the solenoid grounds and the wires( in line fuse) that provide power to the key and trim.. seeing the 2 are related and merc. branches the power for the trim and key from the solenoid connections because the trim should be live even with the key off.

Is it true that the shop manuals for these motors are really comprehensive and useful for troubleshooting? I ask because I'm having some strange behavior with my motor as well and ordered the manual based on advice on TheHullTruth. Ordering one for your engine might help as well.

Mine gets here tomorrow, so I'll know better and can let you know how helpful it is (mine is a Johnson)
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Is it true that the shop manuals for these motors are really comprehensive and useful for troubleshooting? I ask because I'm having some strange behavior with my motor as well and ordered the manual based on advice on TheHullTruth. Ordering one for your engine might help as well.

Mine gets here tomorrow, so I'll know better and can let you know how helpful it is (mine is a Johnson)
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Alot depends on the particular manual...most are good with basic stuff but not as good as factory manuals with service bulletins
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may have gotten this fixed. starter solenoid got too much power and fried itself.... not sure how exactly. I went through and cleaned all the ground and traced the leads back to the key (didn't see an inline fuse though...)


all seem to be okay. it starts and trim works normally (for now, at least.........) I'll take it for a ride on Monday and see how it goes.

thanks for all the replies- these gremlins drive me friggin' nutz