battery terminal crossed by shop 115 mercury I6

demarko210

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I am new to boating as of last July. I purchased a 19ft grady white weekender cc with a 115 hp inline 6 5314656[FONT=Arial, Verdana, Geneva, Helvetica, sans-serif].[/FONT] i took it to a repair shop near me. they clean the carbs, installed a new bilge pump, and did a boat inspection for me. Well after getting the all green i take it to the ramp and try to start and it drain the battery trying to start. so i took it back to the shop an ask them to show me how to start the boat. The guy turn the key and told me the battery is drain. He removed the all the extra wire for a second battery and got confused and crossed the wires up and tried to start the boat. My old battery was fried after that. I would have charged it on my solar panel but now i have to purchase a battery from them.

Doing so the engine fires right up with the throttle advance but it is misfiring somewhere i was told by my auto mechanic that service the boat after that shop damage the battery. he only told me that once we took the boat out fishing. it ran ok on the muffs after he rebuilt the carbs (because he told me the other shop did not rebuild them only cleaned) and cleaned the tank, new sending unit, new fuel lines, fuel pump, water separator and bulb. We had problems with water and black stuff in the gas tank. my mechanic said if they cleaned the carbs the should have check the gas tank. dirty tank clean carbs is what lead to the fuel system rebuild. I did not change the plugs.

Ok the symptom of my problem is when i start the boat in the water and let it run, i feel a bump or bumps through the floor and when idle and wot. my auto mechanic told me that was the misfire. he told me to get a set of wires for the engine because they look like they needed changed. I did not tell him the battery was crossed. My question to the forms is should i replace my switch boxes, ignition coils, and rectifier too? I have not change the wires yet but i have just purchase them along with new ngk plugs. I know i should have gone back to that shop but i am just putting 2 and 2 together as to what is my problem with the engine. I have a shop manual and will try to fix myself. my mechanic help me alot over the summer learning about my boat so i feel it a simple task as long as i have a book, camera and this form.
 

Chris1956

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If you have spark, and it sounds like you do, the stator, switchbox, etc are good. The serial number you gave points to a 1979 motor. If so, it will have a battery-powered CDI ignition and a distributor. Those ign parts are very expensive to replace. The spark plug wires do go bad on those motors, but you can usually see or hear them shorting to ground with a snapping sound and an arc. Those wires unscrew from the distributor cap. The rotor is non-removeable and very fragile, plus costs $200+.

The rectifier is probably bad, if the battery cables were switched. Put a voltmeter on the battery and start the motor on the flusher. Increase the idle speed to 1100 or so, and the voltage of the battery should rise. If so, the rectifier is good.
 

demarko210

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Thanks Chris i have spark and the motor runs. I have a distribute-less ignition however.
 

gm280

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WOW seems the shop that crossed the wire should foot some or all of the bill... JMHO!
 

demarko210

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I agree but it to late now. If I would have known what could happen when this was done i would have made them check this out before hand. My advice to new boaters review boating and boats well before you buy and never tell a shop you are not familiar with boats.
 

Faztbullet

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Reversing battery leads on a BDI ignition usually damages the switchbox or trigger....
 

Chris1956

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OK, then the motor is a 1979 and 1/2. That is when the IL6 went to distributorless ign.
 

demarko210

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Thanks Faz. you said that is damages the switch boxes do you think both?
 

jerryjerry05

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Do a compression and a spark test.

If it's starting and pumps water on the hose.
After dark, in a dark area start it and see if the plug wires or shorting out.

In 1983 I had a late 70's 85hp and the battery leads got crossed(I did it, new to boats) it fried the regulator. It wouldn't charge the battery but ran.
Crossing the lead shouldn't cause the battery to go bad.
How old was the battery?

Feeling a "bump" could be a bad prop?
Look at the top of the forum it should have a sticky that helps synchronize the carbs.
Where you located? You might be close to someone who can help.

The dealer should help pay for any damaged part if they crossed the wires.
 

Faztbullet

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I didnt see where you posted it was a ADI ignition but no it shouldn't hurt switchboxes but will hurt the rectifier..
 

demarko210

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jerry thanks man. Im located in Germantown, Maryland I have my boat parked in Annapolis, Maryland now. I haven't done a compression check but that shop did one for me and it was fine at the time. Then battery came with the boat. we tried to start the boat first time out and drain the battery that's when i went back to that shop to get them to show me how to start it. But the battery should have been changed anyway. I was going to charge it on one of my solar panels but the shop said it was fried. then new battery I would not know if the battery is being charged by the motor because i have a 100 watt solar panel keeping the battery charged also. At the time i installed the solar panel i did not know boats came with charging systems oops.

I have a new prop on there.When we (me and my auto mech) got in the water you could fell these little intermittent vibrations through the floor and we had no reverse. we change the lower unit oil which the lower had a crack in it and nothing but water came out of it. it leaked later after taking it out of the water. I thought the vibration was the lower so i purchase one from ebay. here is the link:

http://www.ebay.com/itm/181584838815...%3AMEBIDX%3AIT

I installed it but when I go into reverse there is a noise and the engine cuts out. I'm thinking I need to adjust the shift cables and that maybe its not hitting reverse all the way. We installed controls and cables too. i attached a pic of controls we use.

Jerry I have already purchase wires and plugs,just haven't installed them yet. This is something I should have done after we did the fuels system anyway. My auto mech use to build and blueprint marine engines for a few years and i watched him work on the boat. From what he said on muffs it runs and idles good after the work we done. My auto mech and the shop that worked on the boat are two different shops.
 
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demarko210

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Jan 2, 2015
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Faz thanks, yes its one of those di ignitions. i will purchase a new rectifier from amazon for 26.00 on Monday.
 

demarko210

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Jan 2, 2015
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Jerry,

I removed my prop that i purchase. it was a black max with the torrque hub. my mechanic put it on for me and come to find out that he let the thrust hub on the prop shaft. the new black max prop already had one on it so i removed it and re installed the prop.
 
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