MERCRUISER 3.0 WONT START

wes21

Recruit
Joined
Apr 14, 2004
Messages
2
HI just pulled my boat out of winter storage and it wont start. It turns over then backfires but thats it. I changed the plugs and wires but that didnt work. I then tried starter fluid but no dice. I think its getting fuel, the new plugs smell of gas. Dont know if I am getting a spark. I have a digital distributer. If anyone can help I would be grateful. engine is a 3.0lx merc
 

Trent

Captain
Joined
Nov 17, 2001
Messages
3,333
Re: MERCRUISER 3.0 WONT START

You need to check for spark at all plugwires while starting. You need a nice "blue spark". Also a compression check would ne good.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,291
Re: MERCRUISER 3.0 WONT START

Just get back to the Basics.........<br />Fuel,<br />Fire,<br />Compression,<br />At the Right Time..........<br /><br />Get All 4,+ She'll Run...............
 

johnkc

Petty Officer 1st Class
Joined
Dec 12, 2001
Messages
388
Re: MERCRUISER 3.0 WONT START

put the kill switch in the run position
 

wes21

Recruit
Joined
Apr 14, 2004
Messages
2
Re: MERCRUISER 3.0 WONT START

okay I have no spark, I have new plugs and wires. any ideas thanks
 

affa

Petty Officer 2nd Class
Joined
May 20, 2003
Messages
199
Re: MERCRUISER 3.0 WONT START

Hi<br />Try this advice I got from Captain HooknFinger when I had the same problem:<br /><br />-Sounds like you have an electrical problem causing weak spark at start up.<br /><br />- You should have full 12 volts at the coil when you are starting the engine.<br /><br />Try these quicky tests... <br />- Attach a jumper wire from battery positive to coil positive and attempt to start the engine. (You really should change the spark plugs before you do this test ), because they are probably junk by now from trying to start the engine with weak spark. <br /><br />*Engine starts ok? with 12 volt jumper connected?<br /><br />Your carb, distributer, coil, plug wires are all fine - Trace the wires feeding your coil in the key 'start' position. Something along there will be junk or grounding out on route to the coil. <br /><br />*No start? - with 12 volt jumper wire connected?<br /><br />- Distributer internal parts or distributer itself may need replacement.<br />- Spark may be grounding out inside distributer.<br />- Bad coil, or coil wire.<br />- Dirty, worn or cracked distributer cap.<br /><br />One test you can try to see if the distributer is grounding out..<br /><br />- Remove the distributer cap.<br />- Attach test light ground to distributer housing.<br />- Turn ignition key switch to (RUN) position.<br />- Use a screw driver to Open and Shut the points causing them to spark while at the same time , you stab the inside housing of the distributer with the test light probe.<br /><br />*Test light does not light up or flicker?<br /><br />- Head for the high voltage coil wire and/or coil.<br /><br />*Test light - lights up or flickers?<br /><br />The internal parts of the distributer or distributer itself may be bad/grounding out internaly.<br /><br />Affa
 

pmgrape

Cadet
Joined
Apr 14, 2002
Messages
29
Re: MERCRUISER 3.0 WONT START

What year is your engine, and does it have electronic ignition or points?<br />If it has points try an emory board (like what my wife does her nails with) and file the points just a little bit.<br />A guy who specializes in ignition systems told me points can glaze up after sitting. This would definitely take away your spark (but so can being married for 9 years).<br />I have to do this if my motor doesn't run for about a month or more.
 

akriverrat

Chief Petty Officer
Joined
Oct 31, 2002
Messages
588
Re: MERCRUISER 3.0 WONT START

also check your harness plugs. a few years ago i replaced my battery and every part in my ignition system only to find a wire loose on the ignition switch. oh well... now i have a spare for everything.
 

cuzner

Senior Chief Petty Officer
Joined
Feb 14, 2004
Messages
771
Re: MERCRUISER 3.0 WONT START

I had the same problem as you ,after 3 days of pulling my hair out I found I had damaged the wires to my kill switch,when the boat started shaking when I was starting it the conection was off and on,causing the spark to do the same. maybe something worth looking at.<br /><br /> jim
 
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