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'71 Evinrude 40HP 40153G -- restoration questions...

boatbuilder57

New member
Hey everyone,

I got a fixer-upper '71 Ski-Twin 40153G and I'm eager to get it running again. I've restored smaller & older engines before, but this one has some features with which I'm not too familiar. Let's begin with the charging generator.

The seller told me that he always "pull-started" the engine...in fact he didn't even know it was an electric start engine when he sold it to me! I was happy to discover that the starter motor & solenoid are in tact (although not yet verified to be working) *AND* there's a charging generator, albeit not connected to anything.

Question 1: Is this a generator or an alternator? Based on age, I'm suspecting "generator", but don't want to assume. I purchased a service manual, and I'm disappointed to see that there's zero mention of this feature; likewise, the parts book makes no mention either. So what do I have? Was this an Evinrude option? Or was this an aftermarket add-on?

Question 2: Regulator....there's none present. Nor can I find much info about what Evinrude used, what the replacement is, etc. Suspecting that this is a generator (not an alternator), I'm going to need something.....so what do I use? On eBay, I see all sorts of NOS regulators for old cars, so I'm wondering if I can use one of those. Guidance is appreciated!

Question 3: the electrical harness in the engine is a mess, but the plug (black, 5 pins) is in decent condition. I'm an electrical engineer, so making a new harness and re-using this plug should be easy, but I'll be darned if I can source the mating female receptacle. I don't need a complete harness....just the receptacle. Can't find it or a part number for it.....only a part number for the entire harness (discontinued).

So let's start there, although I'm sure more questions will come up!

Thanks for your help and support,

Mark
 
Is it a belt driven unit mounted like the starter ?----------Have you looked at the accessories books ?--------How about looking at a 1969 model with electric shift as they came equipped with a belt driven generator.
 
Yes, it's belt driven...and would appear to be factory installed. Accessories book?........I'm unaware of such a thing. Can you point me towards one?

I have not researched a '69, but I will. That said, I always find it scary to assume that parts from one year translate to subsequent years. I've spent a small fortune on wrong parts by making such assumptions.

EDIT: OK...I looked at the 40ESL69R. The charging device is called a Generator, so I'll accept that is fact. http://www.marineengine.com/parts/j...ohnson&section=Generator+Group+Electric+Shift

The regulator....found that, too. $155 bucks? http://www.marineengine.com/newparts/part_details.php?pnum=OMC0383609 Does anyone know the actual electrical specs for it? How many amps is it? Anyone know? I can most likely get one at the local auto parts store. How many amps is it? Anyone know?

Last question: anyone have a repair manual that shows which terminal on the generator is which? They're not labeled, and I'd prefer not to fry anything by miswiring it...
 
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The generator kit is shown here at marineengine.com http://www.marineengine.com/parts/j...rt+40+Hp+Models&yid=34239&mid=34240&sid=35516

Yes, it is a 10 Amp regulator, with a Type A field, and no you will not find any cars using only a 10 Amp system. Using a regulator for higher amps risks burning up the generator armature. There is a 10 Amp Harley Davidson regulator on e-bay now (or at least there was a few days ago when I looked. The mounting pattern is different, so it won't fit in the junction box, which you do not seem to have anyway. There also are 10 Amp solid state regulators for Harleys that some have used successfully. Be careful not to get the 32 Amp, or whatever it is.

Decide if you really need a generator anyway. The motor only used the battery for starting. And a charged battery will last for quite awhile, depending on how much starting and stopping you do.
 
You raise a good point: an awful lot of starting can be done on a charged battery....might not need a charging system at all. For now, it's good to know what I have, so I appreciate the info. I'll concentrate on making the engine run for now; a charging system can come later.
 
Moving on with my tear down / eval / restoration......Two questions:

First: starter motor questions: With a 12V car battery attached, the starter motor runs, but the gear doesn't pop up. Is this a Bendix spring design? i.e. Can it be re-built? Or am I looking at buying a whole new new starter motor?

Second: the electric choke: With a 12V car battery attached, the solenoid "tries" (so it's not dead), but the mechanical motion is not enough to pull in the choke. Is this just a need to rebuild (disassemble, clean, reassemble)? What is the likely problem? My experience with coils (relays, solenoids, contactors, etc.) is that they're either good or bad, and any reluctance to fully function is usually due to dirt, debris, gunk, etc. in the works.

Thoughts?
 
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First things first. Make sure you have adequate battery voltage to the items in question. Check cables, connections, etc. The symptoms scream out Low Voltage!

About the Bendix. It is possible but unlikely that it is stuck/dirty from rust or gunk. But in the great majority of cases, it is a low voltage (here we go again) problem. The Bendix is thrown upward by the instant and very fast acceleration of the starter---which doesn't happen if the voltage isn't there.
 
Jumper cables connected to my running truck......connected with jumper cables (#4 welding wire). Hard to figure that low voltage or insufficient current is the culprit.

But your point is valid, so I'll take another look.
 
Problem fixed.....there was some trash down in the bottom of the motor housing that was keeping it from spinning full speed. A good cleaning, reassembly, and it's running good. The gear "snaps up" just as it should.

Fixed the choke, too. The solenoid draws about 6 amps, and since the ground connection is purely mechanical (clamp to carb), and since it was filthy & oxidized, I had a crappy ground connection. Cleaned everything up and the choke snaps open & shut as designed.

Moving on: can someone explain the purpose / intent of the "locking lever" on the recoil housing that connects to the carb and seems to engage the flywheel? I'm at a loss to grasp the meaning. Is it disallow starting at WOT? Something like that? My service manual is silent to the purpose.
 
That lever locks the recoil starter to prevent starting manually with too much throttle opening.-----There is also an electric switch to prevent cranking at too much throttle.
 
Just think about it. Suppose you aren't paying attention and hand start it in gear, and a fast throttle setting, and you are standing up to better haul on the rope. Guess where you are going to wind up if it starts and the boat runs out from under you. The starter lockout makes sense, doesn't it?
 
You can test the generator by running it like a electric motor. Remove the belt pully and then run a jumper wire from the field terminal on the generator to engine ground then apply battery pos to the armature terminal and the generator should spin. That also polarizes the generator. That is a 1969 motor is it electric shift also? If not the generator was probably a add on. There is a F and A on the generator I just got rid of a generator and regulator I cant remember it the housing or the bottom plate is stamped with F and A. Mastertech marine has wiring diagrams for the electric shift motors you can use a amp guage or a volt meter the charging system starts putting out around 1500 rpms.
 
OK....I'm into the tearing down stage, and today was "drop the lower".

I've done this process on a lot of engines before, but this is a first: The lower wouldn't come until I tugged on it....and when I did, the shaft stayed with the engine, not the lower.

40_HP-lower_-_1.jpg


40_HP-lower_-_2.jpg


What's going on here? What do I do about it? Do I have to pull the powerhead to see what's going on?

Any assistance would be appreciated.
 
The crankshaft and driveshaft splines are jammed with rust.---Likely someone left an o-ring out or forgot to grease the splines.---Fairly common event.
 
Yep, a common problem that should never happen at all. There is a groove around the top end of the drive shaft for an o-ring. The o-ring keeps water out of the splines, and grease in. So, somebody comes along and drops the lower unit for a new water pump or another reason and doesn't put the o-ring back in, or else the o-ring was shot and fell off while reassembling. Whatever the case, water gets into the splines and rusts them into one solid mass. You might get lucky and get it apart or it may be so bad you will never get it apart. OR you may get apart and find the splines are all rusted out of the crankshaft, never to drive again. From what you've said about the rest of the motor, get ready for the worse case scenario. All because of a ten cent o-ring.
 
I figured the powerhead would have to be pulled to see what's going on.....so I un-did everything that needs to be undone (per the service manual), and the powerhead won't budge. I'm not feeling good about any of this.

AND...the mailman just delivered all of my ignition parts, new impeller, etc. from marineengine.com. As of now, it looks like these parts may never get used.

Not real happy right now....
 
As of 30 minutes ago, that's my new favorite expression!

That said is there a "secret trick" for getting the powerhead off? Or is this thing just completely corroded together, never to come apart?
 
I was thinking that, but couldn't figure where to pry. Where should I do it? Between what & what?

I was also thinking about turning the whole thing upside down and spraying PB on the shaft, letting it drip down to the problem. Repeat over & over for a week or so and let it penetrate. I've seen PB work free some really frozen stuff. Might work here, no?
 
So I went to YouTube and searched "how to remove a stuck powerhead", and a video came up of a guy who would show me how.....and he begins to wail on the poor engine with a 5 lb. maul hammer.

Umm....no.

So I went back to the service manual: remove all 8 screws & 2 nuts. See? it says it right there in B&W:

40_HP-powerhead-off_-_3.jpg


On the bench, as confirmed in a previous thread are 8 screws & 2 nuts. And yet, this powerhead is NOT coming off. So I figured my only real option is to turn the engine upside down and spray PB down the shaft, hoping for the best.

So I up-ended the engine, and......you guys are ***NOT*** going to believe this!! There it was: a ninth screw! I took out the 9th screw, and the powerhead literally "fell off"!!

Yup, the service manual is dead wrong! Go ahead & count the holes! And, upon reflection, the picture in the service manual is NOT a 1971 40HP at all....

40_HP-powerhead-off_-_1.jpg


So now I can see the mess, and yes, this shaft is stuck-like-chuck. I'll PB the hell out of it and hope for the best.

40_HP-powerhead-off_-_4.jpg
 
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