IBoats, The Greatest Resource

[jcunningham]

I've learned more about boating in the last month of reading Iboats, than I think I would in ten years of learning the hard way.
I'll keep reading and some day graduate up from asking beginner questions, but for now here's another no brainer for you guys.
235 Evinrude, can't find the serial number. I've read the posts on finding the year of an engine, but unfortunatly I need it dumb down for me. I find numbers stamped all over the place, but they are different, and I wonder if that's from replacement parts.

Ultimately I'm trying to find out why the battery won't charge. The tack works, and I just bought a multimeter to do the test to see if there is voltage. I've been reading about changing the regulator and the rectifier, but I've got no clue what these parts look like or where to find them on the engine.

So I figure its time to determine the year and get a repair manual.

Thanks guys

 

[Randyg123]

Re: IBoats, The Greatest Resource

I am not sure where you would find this on your motor but this is the tag on mine This is off a 1973 85HP so if your motor is of this era, maybe it will be similar. This photo is taken standing behind the boat so the tag is easily visible (not hidden).

The serial number (and model number) should also be found on a welch plug somewhere on your engine. This looks like a freeze plug but i have no idea of its purpose (I am new to al this myself). To find mine, I had someone tell me where it should be for that model. I had to remove the top bracket that my four coils and wire terminals and powerpack was attached to in order to find mine. Good thing I did that too, It turns out that someone had put a different engine on that bracket. So my stern bracket ID said 85ESL73M, meaning 85HP 1973 year, while the model number on the engine itself was a 135ESL75. As someone put, I just got fifty horses for free.

Again, I am just a beginner myself. I would assume you have a tag on the stern bracket like the photo. If not, hopefully someone will chime in and let you know where to find the welch plug or other indicator for your model.

 

[tashasdaddy]

Re: IBoats, The Greatest Resource

if not on the transom mount, look for a plug like this.

 

[ezeke]

Re: IBoats, The Greatest Resource

The 235HP Evinrudes are all crossflows from 1978-1985. If it has the VRO fuel pump it is the end of the list and if it has the twin lift fuel pumps it is at the earlier part of the list.

http://web.archive.org/web/20011024175639/www.evinrude.com/docktalk/modref/evmodyr/EHP235.html

The early 235HP motors have the unregulated type 10 AMP rectifier with a separate voltage regulator. Look for a triangular base with a cylinder protruding from it.

The last models had water cooled regulated rectifiers inserted in place of a lifting eye.

The 10 amp rectifier is sufficient to maintain a good battery if the battery is not used for much other than starting, tilt and trim, and gauges -provided that the battery cables are in great shape and the grounds are good.

There are suggested methods By Mr. Joe Reeves for testing the unregulated rectifier and limited testing of the water cooled type. They are found in the Engine FAQ forum on this website.

 

[jcunningham]

Re: IBoats, The Greatest Resource

It's a higher priority now,
The first tank ran out of fuel today and after changing to the second tank,
we didn't have enough battery juice to crank it over. I tried everything I could...we floated for a while before flagging down a tow.

Thanks guys,

 

[jcunningham]

Re: IBoats, The Greatest Resource

So my wife thinks she has found the problem with our boat. It always runs good at the start or about 2 hours. Then the engine slows down and has about half power. When it died today it wouldn't start again unit the battery charger had been on for about ten minutes. Is it possible that a low battery is draining and once low enough it is killing the engine?

 

[ezeke]

Re: IBoats, The Greatest Resource

The ignition system and the starter motor are not related. The battery is not required at all for ignition. In fact, if you were strong enough you could rope start the engine and run the motor with no battery.

The battery needs to be strong enough to power the starter at about 300 RPM. That takes a fully charged, powerful battery. If the motors slows down in actual operation, it is related to fuel supply, spark or compression. If the engine overheats it will also bind and slow down.

 

[samo_ott]

Re: IBoats, The Greatest Resource

So my wife thinks she has found the problem with our boat. It always runs good at the start or about 2 hours. Then the engine slows down and has about half power. When it died today it wouldn't start again unit the battery charger had been on for about ten minutes. Is it possible that a low battery is draining and once low enough it is killing the engine?

At least your wife is trying to help solve the problem, most wives would not be too happy if they were stranded out on the water! I know mine would sure not be!

 

[tashasdaddy]

Re: IBoats, The Greatest Resource

read this.http://forums.iboats.com/showthread.php?t=158071

 

[jcunningham]

Re: IBoats, The Greatest Resource

I found the model number, it's a 1985, 235hp. Now I think it's time to buy the manual.
I was reading the FAQ post about testing a rectifier. It says that if the rectifier is blown that the tach simply won't work. But my tack works fine. It does sputter a little but that only tends to be when the engine isn't running good. So if the tach works why won't the battery charge?