Coils and Ballast Resistors - 1977 OMC Ford 302

RogerBoat

Seaman Apprentice
Joined
Mar 5, 2011
Messages
37
Thanks guys, I can't tell you how valuable your input was to identify a fuel pump. Redrig, the part number you proposed was the right one. Thanks. Now for a harder question.

I said I had an ignition problem. I put a dwell meter on the coil and concluded it was below recommended reading, so I pulled it off to discover the only markings on it was "6 Volt.no part number or vendor. " What???? This is a 12 volt system. After spending 4 hours on the internet I concluded perhaps this is not necessarily wrong. So, I uidentified Sierra part 18-5437 which seems to match a OMC part number listed in various vendor sources. And it is 12 Volt.

But here is the rub, What Ballast Resister should I get? Surely a 6 volt coil and a 12 volt would require difference ballast resisters? How do I match the correct ballast resistance to what the coil requires? neither device provides information as to its application to the other. I found two vender parts claiming to be for a marine 302 Ford engine, but no literature anywhere to match the two parts together or even to decide if I can use the existing ballast in the boat. Am I wrong to think different Ballasts have difference resistance capabilities? I don't want to burn up plugs and points the first time I go out. Any advice out there?

The other option I am considering is to convert to electronic ignition wherein hopefully a kit would have all the right parts for the application. But I have read a lot of negative reports and seems to be some question about Marine applications.. Any opinions?
Thanks
 

Bondo

Moderator
Staff member
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Apr 17, 2002
Messages
71,095
The other option I am considering is to convert to electronic ignition wherein hopefully a kit would have all the right parts for the application.

Ayuh,...... I've done the Pertronics up grade on many older motors, all with great success,......

As for yer set up, hook it up, 'n Try it,......

The resistor just lowers the voltage fed into it,......
 

Redrig

Master Chief Petty Officer
Joined
Oct 13, 2009
Messages
860
Glad to hear the fuel pump number helped

have you by chance seen this link ? Its an old school OMC parts catalog that gives you all of the part numbers that you can cross reference to replacements , it helps me all the time.

http://epc.brp.com/Index.aspx?lang=E&s1=04a25590-6958-4f36-bd2c-c3559b5479dd

your original ballast resistor is listed as 0981654 , so that is what "should" be in there, or an aftermarket equivalent
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,297
if you maintain the points every year, you only need to change them every 15 years or so.

that being said, putting a dwell meter on the coil and getting a reading that is not correct indicates that the gap in the points is not correct.

why did you need to change the coil, etc. vs simply filing your existing points, re-gapping, verifying with the dwell meter, and then setting timing?

the points are manufactured by Blue Streak (a division of Standard motor Parts)
 
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