ignition coil

[markwh]

i just changed my ignition coil in my 87 OMC 4.3L cobra sterndrive as i have been having issues with engine running rough, i've changed plugs, water/fuel separator, done a carb kit, checked rotor cap, looks in good shape. and was still running rough. than i noticed oil all over the engine, and looked like it was coming from coil, and was told that meant it was no good, engine still fired up on old coil but was running rough, put new coil in tonite and it won't fire up at all and this engine has always fired up right away. when i bought this coil they cross referenced mine and said it was for a 1990 and above, don't know if that would make a dif or not ?

 

[Levinz11]

Re: ignition coil

I would do a FULL tune up. Points, condenser, cap, etc. Are you saying that the coil busted or blew up and threw oil all over?

 

[markwh]

Re: ignition coil

it didn't blow up it was just spitting oil out the top all over the engine

 

[Howard Sterndrive]

Re: ignition coil

0383444 COIL ASSY. Ignition, is for a 1987 4.3
and Sierra 18-5437 is the aftermarket replacement from NAPA

1987 4.3 has a resistance wire for run, and a resistor bypass for start, so a coil specifying "for use with external resistor" is what you want.


Or, you can replace the resistance wire with regular wire, and use a coil that says "internal resistor" (which is nonsense, but that's how they label them when they don't use an external resistance wire).
The $39 tractor one from TSC works well in my experience on boats - it requires the resistance wire be removed/replaced. The starts won't be as hot, but that's not an issue.

 

[markwh]

Re: ignition coil

the one i purchased does say external resistor, i switched to my old one and my motor fired right up, so it must be the new coil is wrong, not sure what dif is year to year but if they sell dif ones there must be a reason, so i'm going to bring the new one back hopefully they take, sometimes sticky about electrical stuff

 

[Howard Sterndrive]

Re: ignition coil

probably not wrong so much as defective

 

[markwh]

Re: ignition coil

brought that one back and got another one, this one fired up but didin't resolve original problem, maybe i'll change points, condensor and cap, just don't no where to stop, last try then i'll have to pay someone to figure it out

 

[Don S]

Re: ignition coil

Points and condenser should have been your first thought to change. Those are maintenance items and should be replaced yearly for best running.
Be sure to set dwell, the the timing after installing the new ones.

 

[markwh]

Re: ignition coil

sorry not real good at pinpointing problems, just workin my way around the engine, tryin dif things from dif opinons