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1978 35 hp evinrude battery charge issue

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dmorray

New member
hey guys, after owning a 1976 25hp rude pullstart for years, i finally decided to (upgrade) to a 1978 35 hp elec. start motor. i absolutley love the motor, it runs, idles, starts, etc. with perfection, (i love these older motors) anyway,.....my question is this: i have two batteries on the boat, one for trolling motor, and one (brand spanking new) marine battery just for engine starting. now, every now and then i will run the trolling motor battery*dry, and use the starting battery for a little longer fishing time, and if that one goes dead then i can simply use the old reliable pullstart on the motor to get me home. again,.......to the point,.......should my motor re-charge the battery like a vehichle with an alternator??because most times when i take it out, i only use the starting battery to run the motor, and even after a full day of fishing (and a 40 minute ride back to the boat ramp) which i would think would be enough time to recharge the battery after only one crank for about 3-5 seconds, it still only shows 70-80% battery life when hooked back up to the charger. and keep in mind this is when i havnt used that battery for anything else but engine starting. i can only assume the power pack, magneto, alternator, or whatever it is called is working, because it will run on pullstart even without a battery. im sorry, i know im long winded, just wanted to give you the full spectrum!!!! any advice or knowledge of the issue would be appreciated!!!!!
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thanks!!
 
That engine has what is called Magneto Caapacitance Discharge ignition, meaning it is self contained and dos no use battery voltage to energize the ignition. A stator under the flywheel provides AC voltage to the powerpack capacitor in order to energize the ignition.

The majority of the 1978 35hp models incorporated a alternator. Look for a rectifier which would be attached to the stator wiring at a terminal strip. The rectifier could be one of two types... 3 wire or 4 wire. The 3 wire would be yellow, yellow, red, the 4 wire would be yellow, yellow, yellow/blue, red. A rectifier being present = alternator.
 
thank you for your reply, it sort of helps me, this electric start motor definately has some components that my old pull start did not, for instance there is a small round electrical component that the wires from the ignition coils pass through,(this is right beside and in front of the coil packs) also there is a larger (apprx. 1.5 " x 3.5") black electrical component on the port side of the motor (right beside the cylinder head to the left if faceing the motor from behind) these same wires seems to connect to this. they all originate from under the flywheel on the starboard side. im assuming this is what you are speaking of. what is confuseing me is that the color sequence for the wires is brown, brown/yellow, white/black, black/white. any further infor would be great!
 
Black component with wires of those colors would be a powerpack.

A rectifier would be about 1" tall, round in appearance about the size of a half dollar, and have a triangular base. It would be attached with two different size screws/bolts (usually). On that model, it would normally be installed on the starboard side of the engine just to the rear of the carburetor area..... and the wires would be colored as I stated.
 
ok, we hit the nail on the head with that one!! thank you so much!!! i defin. do not have the rectifier. it appears that it was removed at some point, im assuming this because where it should be, there is a new bolt replaced in one of the various holes. now, how do i know that is all i need to replace? im assuming it was taken off by the mechanic of the guy i bought the motor from. he serviced it before selling. that would make sense if he saw that it was faulty and didnt want to spend the extra money for re-sale,....as it is obviously not a must have on the motor. or are there more parts to look for before i go replacing just the rectifier? it is a model 35802r, if that helps.
 
How do you know if all you need to do is replace the rectifier?

Remove the flywheel so that you can inspect the components installed upon the armature plate/timer base.

If you have a couple small components mounted there, you DO NOT have a charging stator.

If you have one fairly large one piece sealed ring installed, that would be a stator that combines the ignition and charging system and in which case, then yes, the engine would have a charging system. Possibly you can see the stator if it exists by simply looking closely under the flywheel.
 
A puller that uses 3 bolts and the 3 holes in the flywheel hub.----They are 1/4-20 bolts.----Do not use a gear puller with 3 arms !!
 
If you have the yellow wired coming from under the flywheel, you have the alternator stator---unless the guy removed that also. Do a resistance check between any two of the three yellow wires. Should show a few OHMs (don't know exactly how much without looking it up) If is shows open circuit something is amiss.

EDIT: Oops, eight year old thread. We were not supposed to reply. Start a new one
 
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