Pinion drive gear not engaging flywheel

I have a 1975 Bayliner Mosquito powered by a 1975 Mercury 850. I have had a problem with the pinion drive gear not popping up to engage the flywheel in the past, but was able to tap it a few times with a wrench and it would "fix" itself. No luck this year. It spins when I turn the ignition but I cannot get it to engage at all. I am wondering if this is something that I can disassemble and clean and it will work again or if I need to find a new used one, thanks in advance for any insight!

Jerry

Re: Pinion drive gear not engaging flywheel

First thing is to measure the voltage between the hot and cold wires on the starter....measure the studs, not the cable clamps.... while attempting to engage the starter. If not 10v or greater, start with the battery. Have it load checked. It needs to hold at least 11v at 200 amps....WW can do that. Then clean up all the terminals, not outside per se, but inside where the current flows between the battery and the starter studs. Take them apart, clean them and replace them. When finished there is a battery spray you can buy at WW where they sell batteries, that you can spray on the contacts, after reassy. to help in preventing corrosion....don't forget the lead posts where the cables connect to the battery. WW sells a wire brush also made specifically for the purpose in the battery department.

Then, after you fix all that, put some lube on the starter shaft...I use Lubriplate chain lube (WW also) for most everything as it stays put and leaves a moly film. Rotate the Bendix up the shaft to ensure that it is free to move.

If, after all that you still have problems, then you need to check your solenoid terminals input and output and ensure that there is no voltage drop across it.....if so, get another... If ok, you can dig into your starter and put in new brushes which you can probably purchase either, both here.

The Bendix has to be spun at a high rpm to get it to run up the shaft. Problems I mentioned can prevent that.

HTH,
Mark

Re: Pinion drive gear not engaging flywheel

WOW! great answer, the only thing I could add is well,,,,,,nothing. Just do all that above.

Re: Pinion drive gear not engaging flywheel

Canyon Runner said:

It spins when I turn the ignition but I cannot get it to engage at all.

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Agree with all of the above....but be sure your battery cables aren't reversed.

Re: Pinion drive gear not engaging flywheel

schematic said:

Agree with all of the above....but be sure your battery cables aren't reversed.

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CAREFUL HERE!!!!!!!. YOU DO NOT WANT TO BE PLAYING WITH YOUR BATTERY CABLES.

Proper cabling is black wire to case of starter and other end on battery -, or it may go to the engine block and there may be a black jumper wire from there to the starter case. Usually it's to the case due to the high current required for starting.

Red wire is usually tied to the input post of the starter solenoid (convenient distribution point for 12v.....other small red wires will be on that terminal also) and the other end to battery +. Other side of solenoid, also red and short, goes to the hot/insulated terminal on the side of the starter.

Reversing the battery terminals, just for a second can blow the diodes in your rectifier. Don't experiment.

Mark

Re: Pinion drive gear not engaging flywheel

Thank you for all the responses. Before I checked for replies I called the local boat shop asking about their lead time, when the guy told me two weeks my heart sunk, but when he asked what the problem was and I told him he said that a lot of the time that could be fixed with a couple shots of WD-40 down the shaft. When I got home I gave it a shot, but she still spun freely with no extension, bummer. I then read your replies...I do not have a meter, so was unable to check the voltage, etc. but I did inspect and clean the battery terminals. Now the embarrassing part, I began to wonder if the battery was connected correctly, and when I connected my depth sounder it would not turn on, so I reversed the terminals and low and behold the depth sounder worked. I decided to turn the key and hope I did no damage if they were backwards and she fired right up with a little choking! So now the question begs, as Mark suggested, did I do damage to the rectifier all those times trying to get the motor to start with the terminals reversed??? Can I safely say that since it did start I somehow managed to do no harm? Or is this going to bite me in the *** while I am out on the water...

On a side note, I am quite electrically challenged, so forgive my ignorance, but is there a reason black is negative on the boat but it is positive on my trailer?

- Jerry

Re: Pinion drive gear not engaging flywheel

Canyon Runner said:

Can I safely say that since it did start I somehow managed to do no harm? Or is this going to bite me in the *** while I am out on the water...

- Jerry

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There is no question......the rectifier is cooked. Replace it. It will run even when rectifier damaged.