My Mercury 25hp won't start... Help!!

[kimberman45]

I recently got a 1994 17' Basstracker with a Merc 25HP engine. I ran it several times over the past couple of weeks without incident. <br /><br />The other day, I filled the gas tank (and added 16oz. 2 cycle oil for the slightly over 6 gallons of gas - 50:1 mix), and took it out for a few hours. No Problems. <br /><br />Went fishing next night and used the trolling motor with the running lights. I'm pretty sure that my lights run off the cranking battery, and I know the the trolling motor runs off of a seperate marine battery.<br /><br />Went to trailer the boat, and started the 25hp. It started right up. When I put it into reverse and gave it gas, it stalled. Started it back up (it started right up again), gave it gas in reverse again, stalled again. Tried to start it again, and only got a "click" when I turned the key. <br /><br />I then used the trolling motor to trailer the boat, and hauled it home. At this point I figured I probably flooded the engine by not letting it warm up sufficiently, and the electric starter problem could be a result of either a low charge on the battery or a bad starter (or solonoid), or maybe even a combination of both. I put my battery charger on the cranking battery overnight and brought it up to a full charge. <br /><br />Next day, I charged the marine battery up to full as well. Still only "click" when I turn the key. Battery termninals are clean. Seems to have plenty of "juice" at solonoid. Starter motor shaft is not stuck. Engine is not stuck.<br /><br />Now, I cannot start engine with pull start either. It doesn't even try. Saw some gas by the exaust (mixed with oil), and figured the engine was probably flooded again. Checked the kill switch, it's in the "run" position. Double checked that the key was turned on as well.<br /><br />Pulled plugs, they were wet. Dried and replaced them, still won't start. Engine has spark. <br /><br />Back to the starter problem - bought a solonoid and replaced it (trying least expensive way out). Still only "click". Tried applying direct voltage over + and - terminals of the starter motor and it doesn't spin (I detached the wires from the solonoid before doing this). This is leading me to believe that the starter is bad.<br /><br />It was fine one minute, then dead the next. I'm running out of ideas. Could a solonoid cause both the problems I'm describing? Having voltage directly applied to the starter and not seeing it spin would seem conclusive that the starter is bad or the voltage isn't enough (to me). Would you agree to that? <br /><br />What could I test next? I'm ready to just take it to a mechanic, but time and money are both a little scarce right now.<br /><br />Any ideas?<br /><br />Any suggestions would be greatly appreciated...<br /><br />Thanks,<br />Jim

 

[CJ ROOSTER]

Re: My Mercury 25hp won't start... Help!!

kimberman. use a good set of jumper cables. apply red to your wire post. and the ground to a good ground on the starter. it might be easer to take starter off. also check all wiring connection that they are tight. also if the starter does work off of the motor. start looking at the neg side of your battery cable. it sounds like a wiring proublem. but the armiture in the starter might be grounding out not letting it run. <br />Keep me posted.<br /><br />CJROOSTER

 

[DLJ]

Re: My Mercury 25hp won't start... Help!!

Are you sure the motor is in neutral-just a thought because I have done that before and all it does is clicks until put into neutral. DJ

 

[kimberman45]

Re: My Mercury 25hp won't start... Help!!

I managed to figure it out. Very strange coincidence... Starter AND spark plugs go at precisely the same moment?!?!?<br /><br />First, I'll never underestimate the power of spark plugs again. I installed new ones, and the *&^$#@ thing fired right up on the first pull.<br /><br />As for the rest, I first replaced the solonoid. Same symptoms as before. I removed the starter, gave it 12 volts, and got nothing. <br /><br />I took it apart and cleaned it up, then I was able to get it to spin on the bench. <br /><br />I put it back on the motor, nothing. <br /><br />Uninstalled again, would not spin on the bench. <br /><br />Took it apart AGAIN, and found a bad ground braided wire rivited to the end cap. <br /><br />I drilled a hole n the end cap and re-attached the wire. Runs like a clock now.<br /><br />Thanks a million to those of you who responded to my plea for help.<br /><br />One last thing... I found that going to www.mercurymarine.com and looking at the parts listed in "Express Parts", I could not order an end cap or brushes.<br /><br />When I called the "factory autorized service center near me", they were able to order precisely what I needed, but the web site claims I would need to order a whole new starter, as those parts allegedly only come as part of a complete assembled starter.<br /><br />If you order parts from Mercury, it might be wise to inquire with the local shop before taking a plunge and buying more stuff than you really need.<br /><br />Total cost of repair? About 2-3 hours of my time and two spark plugs.<br /><br />Thanks again!<br /><br />Sincerely,<br />Kimberman45

 

[Walter]

Re: My Mercury 25hp won't start... Help!!

Ya know...I wish someone WOULD explain how spark plugs can fail like that. I won't go into details (it's too embarrassing), but somehow or another...the plugs on my newly rebuilt MerCruiser Chev 350 became fuel fouled. She cranked but just wouldn't light. My buddy says, "Let's change the plugs!" I said, "Hey, those are brand new plugs!" What the heck...it's only money. Installed another new set of plugs and VA-ROOOOOOOOOM!!<br /><br />So...when plugs get fuel soaked (even if you pull them and dry them off) ...what the heck causes them to not fire any longer???<br /><br />Inquiring minds want to know....<br /><br />Walt PS Congrats on getting your Merc back in the running... Another fine example of something so relatively simple to fix causing a major headache! Great job of diagnosing and repair!