HELP MerCruiser left me stranded

Greetings all, I'm new to the forum.

This is my first boat its is a 1986 Renken Bowrider with a 2.5 Mercruiser I/O. I have a very limited knowledge about boats and a decent knowledge about engines.

A couple of weeks ago out on the water the boat was running fairly well. I was running about 2600-3000 rpms crusing along when the boat died instantly. Still would turn over but no fire at all.

Yesterday I pulled the fuel line and there is sufficent fuel getting to the carb. I also dumped fuel directly into the carburetor and still no fire.

I then turned to the coil. I unhooked all wires from it. A resistance test from the two outer poles shows 1.1-1.4 ohms resistance. I ready online that a typical coil should read .75-.81 ohms. I then checked from one of the outer poles to the middle contact where the coil wire goes (does it matter which pole u test from?) I found a resistance of 7k ohms. I read online that 10k-11k ohms is typical.


Is this enough data to determine the coil is the culpret!

PLEASE help me get back out on the water

Re: HELP MerCruiser left me stranded

It appears the manual I am looking for is no longer available.

Does anyone know the proper coil specs?

When checking the points look to see if there burnt/discolored?

Re: HELP MerCruiser left me stranded

Are you sure you didn't accidentally bump the kill switch that the lanyard is attached to? On some boats, it's easy to do without realizing it.

Re: HELP MerCruiser left me stranded

What is the kill switch you speak of. The boat has an igntion key switch is there another switch? The motor will still turn over.

Re: HELP MerCruiser left me stranded

What is the kill switch you speak of

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it's a switch that interupts the ign. circut of your engine. you wear a line (lanyard) that attachs to you. if you fall overboard. the switch is tripped and inturpts the ign. turning off the engine..

http://boatingsailing.suite101.com/article.cfm/boat_engine_kill_switches


it's what this guy was wearing that prevented him from being chopped up by his own boat..
http://www.youtube.com/watch?v=1UEETjztLqI

Re: HELP MerCruiser left me stranded

I dont think my boat has such a device

Re: HELP MerCruiser left me stranded

many old boats don't. including mine..

have you done a minor tuneup ontoit lately?

hate to admit it. but mine did the same thing this spring. just up and died instantly. in my case. it was my own error. i didn't get the distributor cap back on tight after replacing it for this summers use. it was crooked. the rotor got a bent contact that connects with the distributor cap carbon button. my issue was probably not to common though. but it's a thought. i'd start with the tune up if ya've not done one and go from there...
i also clean up as many wiring connections that i can get my hands on. you'd be surprised at the difference between a 1 year old connection and a freshly shined up one. they're noticeably different looking after cleaning. yes, ya have to take them apart to clean them.. i use emery cloth to shine them up..

Re: HELP MerCruiser left me stranded

Does anyone know the proper procedure and specifcations for testing the coil.

I get spark when grounding the plugs but it looks very weak.

Re: HELP MerCruiser left me stranded

go buy a new coil older boat and car coils are the same i think or just for testing.

Re: HELP MerCruiser left me stranded

assuming it's not ddis

from the s/m...

coil

1. use magneto analyzer for test.
2. check coil for the following:
a. coil power test
b. coil surface insulation test.
c. coil continuity test.
d. primary resistance test.
e. secondary resistance.
3. replace coil if test results are not within specifications.



that's what it says. the magneto analyzer is a mercruiser specialty tool. i've no idea how it works as i've never seen one.. some of them tests i'd assume ya could perform with a vom. some maybe not. surely i'll be corrected if someone knows exactly what ya need to do..

maybe take the coil to yer mercruiser dealer and have them test it. i'd guess a dealer would have the proper tool to do the deed.. i reckon they'll charge ya for the test though. which may make it more economical to just R&R the coil depending on it's cost...

ya didn't say weather ya did yer tuneup? like points and condenser.. that'd effect the coil too for putting out properly..

Re: HELP MerCruiser left me stranded

I havent performed a tuneup I really should.

It just bugs me how it died so quick, makes me think its a simple fix.

About how much for points rotor crap and condensor, I would probably be going to Napa.

Re: HELP MerCruiser left me stranded

I havent performed a tuneup I really should.

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yep, ya really should...

check this out too from the adults only sticky thread.. http://forums.iboats.com/showthread.php?t=192804
ya should do all that stuff if ya want to have a happy boating summer instead of a summer working on your boat...

About how much for points rotor crap and condensor

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oem, $50 + or -...

i'd go with mercruiser parts myself...
here's an example of what napa provided me for a cap..



the oem cap is on the left. note the larger contact area. more rings around the carbon button. it was also noteably heavier than the napa cap... i don't know if the cap napa provided me was marine duty. but i certainly specified marine duty... i was so unhappy with it, i took it back and used an old cap i had on hand from last year...

Re: HELP MerCruiser left me stranded

Thanks for the good info Ziggy.