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sjones
04-20-2011, 07:50 PM
I need to replace coils on my kicker. it is a 1961, 5.5 hp. Evinrude fisherman. Is there any reason I would buy one maker or the other a CDI, Mallory, OMC, or Sierra.

Thanks,
Sean

Mav186
04-20-2011, 10:35 PM
Hi Sean,
I'm not sure really what the differences may be between all of them, or what buget you have to live by...but my philosophy with my boat engines is I don't scrimp on the quality of my engine repairs (kicker, main or bow mount) because each type is designed and used for a specific function, and that is to put fish on the deck and get me and my loved ones back safely. I would buy what my budget would allow...just my 2 cents.

sjones
04-20-2011, 11:11 PM
Price was not really the issue @ $5-10 diff in price for the pair. I just wanted to know if there was a benny of one over the other. The question is, is there a good, better, best? I just did not know the answer. If they are all the same I guess it does not matter.

lowe1648mt
04-21-2011, 12:46 AM
If it was my motor, I'd replace the points, condenser, and top seal along with the coils. As the motor is an oldie and I assume a goodie, I'd do it all. If you can get the parts. Might not find them in another 5 years. I would stay with OMC - they probably will have all the right parts. I had a 1961 Johnson 10 hp and a 1952 2.5 Jonson. Great motors. Any oil under the fly wheel?

sjones
04-21-2011, 10:13 AM
Everything looks good under the flywheel. I was going to replace the points, condensers, and maybe the seal. The first time I tried to run that motor this year it was 28 deg. and it did not fire. So when I got it home I started looking at stuff. Every thing came up good till I checked spark, that is when I found no spark on the #2 cylinder. Looked in the inspection hole and found the coil was cracked. I am going to do it all while I am there and have already done the carb as of last week. I just did not know if there was a reason for buying one or the other of the manufactures. This boat and motor combo was my Great Uncles and it is a 1959 Crestyliner, with a 1964 Evinrude 40 horse, and 1961 5.5 horse. I will get the kicker running today or Friday.

lowe1648mt
04-21-2011, 11:58 AM
The 40 hp Johnson & Evenrude were particularly well known for taking out the top seal and getting oil on the points. The 5.5 not so bad.

fishbiker
05-25-2011, 10:08 AM
The function of any ignition coil is to convert a low voltage (12 volts or less) into a voltage high enough (25,000-plus volts) to jump the spark plug gap and ignite the fuel-air mixture in the engine cylinder. It performs this function by making use of the principle of induction. The internals of a coil consist of primary and secondary windings of wire coiled around a vertically mounted soft-iron core. Because of the ratio of primary to secondary windings, a small input voltage is transformed into a very large output voltage. One of the differences between a conventional breaker-point-style coil and a Transistor Ignition (TI) coil is the ratio of these windings. A TI coil uses higher ratio when compared to a conventional coil. In addition, the TI coil uses larger diameter wire in the primary winding which decreases the resistance and allows the coil to operate at higher current levels (approximately 7.5 amps). This high current enhances the coil's ability to produce a high output voltage.

An important point to remember is a conventional point-style ignition system is current-limited due to breaker point life, where a TI system is voltage-limited due to the electrical components used in amplifier construction.

A coil intended for breaker point usage will not work in a TI System for two reasons.

One is the turn ratio -- due to the fact that a TI system operates at lower voltage (2.5-7.0 volts) there is not enough "step up" capabilities in a conventional coil because of a relatively low turn ratio.
The other is the operating current -- a conventional coil has high primary winding resistance in order to control breaker point current to a value of approximately 4 amps. When this low current is combined with the low turns ratio of a point-style coil, the result is a substantial reduction in output voltage in a TI circuit.