2000 Mercruiser 3.0 w/ EST wont start after rain

[kramerpage]

While vacationing in Michigan the boat ran great for four days. Then two days of hard rain. Went out to start the boat and it would not start. Removed engine cover and smelled wire burning. Found ignition coil really hot. Could not leave hand on it. Turned key off and removed wire harness plugs to let dry. Returned to boat three hours later and plugged harnesses back in and boat would not start. Last day of vacation so I packed it up on the trailer a day early. Ordered new ignition coil. Installed coil. Verified 12v at Purple wire on primary side of coil. Turned motor over several times. New ignition coil is hot again. Covered up boat. The marina I bought the boat at when new went out of business this winter. There are no marinas in the area. I would have to tow it up to Lake Erie by Sandusky where I have a Larson at a slip in a marina. I would like to try to shoot it myself with your help. I have a fluke multimeter. Thanks

 

[fat fanny]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

Try checking to see if condensation set in under the dizzy??

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

OK, Ill check under the dizzy FF when I get home tonight and post findings.

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

Got home and made several checks but cannot get spark from coil.

Coil:
Purple wire has 12v with key on and 11.2 while cranking
Grey wire has 2 ohm@1k resistance to ground both keuy on and cranking
2 wire harness going to ditributor Pink wire has 6 ohm @1k resistance from end to end unplugged

Distributor
Harness plug withe to grey not used
one white green with resistor shows2ohm@1k with kill switch OFF
same white green shows open with kill switch ON

pick up coil
white
green

both wires to distributor case ground show open
green to white show 816 ohm

So I hooked up a sparkplug to the coil high tension post and grounded it good with two gator clips and cannot get any spark. I am begining to think my new coil is cooked also. Thanks for any help.

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

My Clymer manual has a troubleshooting section for just this issue. No spark.
I got all the way to the second to the last test and it states to replace ignition module. So I ordered one. I was hoping it was the tachometer shorted out but that was not it. I guess I'm whistling to myself on this forum but maybe it will help someone. Will update after module is installed.

 

[fat fanny]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

Just make sure you buy A/C Delco oem mod the after market ones don't last very long just my experience. Also make sure you check all the inline fuses in the harness there should be one incased in a boot before the large pin connector.

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

FF,
I purchased a Mallory Model Number: 9-29800 module. I hope it will perform well. It wasn't cheap but 20.00 less than an ac delco. A boat should be able to set in the rain. It has before numerous times. I still think it originated in the dash instruments but cannot prove it. They were exposed. Everything else is under cover, unless it is all coincidence. We'll see.

 

[fat fanny]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

Well another option is to use this stuff the navy came up with years ago and it does do what it's name abreviation says it does WD 40 (water displacement formulation#40) spray it on all your contacts and electricals it works it will disolve condenstaion almost instantly I use it when I lay my rig up for the winter, and when I suspect condensation intrusion. Good luck

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

New Module didnt do it. Im throwin parts at it now. Will have to tow 130 miles to the marina. Ill post the outcome.

 

[kramerpage]

Re: 2000 Mercruiser 3.0 w/ EST wont start after rain

The 2000 3.0L mercruiser with no spark solution was a defective tachometer. The technician stated when the coil gets hot like that its a grounded tachometer since as soon as the key is turned on the coil is being grounded. So after all the bull**** I went through it was a .5 hr fix for a good seasoned tech. I was happy to pay him. So if your 3.0 wont spark just take all the wires off the tach.