1971 Johnson 50ESL71S What do I do?

FISTer

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Sorry if this is a double post... It seems the forum deleted my original post.

I just bought an old bass tracker with a 71 Johnson 50hp model# 50ESL71S

I work with the previous owner, and his dad was the original owner, so he knows it's history and I trust what he's told me. He told me that before it quit running, it ran great. He said that for the past several years the motor quit charging the battery, then a couple of years ago it quit running (no spark). He thought it was the power pack, so he replaced that. Didn't fix it. It at least needs a new stator. The stator has a burned/melted spot on it. I'm going to replace that, then see if it will at least try to run. I don't want to pour a lot of money into it until I know it will run.

If the stator fixes it, what else should I do? I'm planning on at least: new plugs, clean/rebuild carbs, change gear oil, change fuel filter, possibly change water pump impeller.

If the stator doesn't fix it, where should I look next? Coils?

The lower unit is stuck in gear, and I can't get it into neutral. I noticed when looking through parts diagrams that it is an electric shift. How do I get it into neutral? Any ideas?

It doesn't have power trim. Is there another model with trim that will interchange with mine? Maybe I can find a used one.

The prop isn't in horrible shape, but it doesn have some decent dings in it. Where can I find a good used one? I don't really want to pay for a new one. What pitch should I get?

If I do replace the impeller, is there any special trick to getting the lower unit off, or does it just unbolt and drop right off?

That's all I can think of for now. I'm sure I'll have more questions later.
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

Well, I've answered one of my questions after scanning through old threads. I didn't know that the ignition has to be on for it to go into neutral.
 

5150abf

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Re: 1971 Johnson 50ESL71S What do I do?

Get an OMC manual for this engine,NOT Clymers Seloc or anything on CD a factory manual, it will have everthing you need to actually diagnose the problem rather than guessing and throwing very expensive parts at it.

They can be had here at iboats or poke around on Ebay but get one for your year and HP, it will cover you engine and your engine only.

Form reading your post it does sound like it is the stator but with the manual you can test it and be sure before you drop $200-$300 on one.
 

steelespike

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Re: 1971 Johnson 50ESL71S What do I do?

One of the first things mentioned when discussing the electric shift is the need for a fully charged battery and a fully operational charging system.Probably not directly affecting the ignition problem.But important in the operation of the motor.
You should have a factory repair manual.I believe there are reprint factory manuals here at boats.
Careless or improper trouble shooting of the ignition can cause damage.
 

Faztbullet

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Re: 1971 Johnson 50ESL71S What do I do?

I'm planning on at least: new plugs, clean/rebuild carbs, change gear oil, change fuel filter, possibly change water pump impeller.
All these you posted needs to be addressed and serviced. Remember the electric shift requires a special gear oil.
Is there another model with trim that will interchange with mine? Maybe I can find a used one.
This was a accessory that was added on and only a power tilt was offered at that time.. If you want trim did a CMC unit.
f I do replace the impeller, is there any special trick to getting the lower unit off, or does it just unbolt and drop right off?
Just make sure you disconnect the shift wires and tie on a heavy piece of twine to fish them back thru.. As suggested try to find a manual..
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

Thanks for the replies.

Upon further inspection, I found that both coil housings are cracked. I've ordered a service manual, stator, coils, carb kits, and a water pump kit. Now I just get to sit here and wait till it all shows up.

The only gear oil I've been able to find locally that says it is rated for the OMC electric shifts is citgo supergard.
Will this work?
http://www.academy.com/webapp/wcs/stores/servlet/Product_10151_10051_10681_-1?N=573959314

I had looked at the CMC trim units. I'd love to have one, but I can't justify spending $600 for the trim unit when I only paid $800 for the whole boat.
 

rockyrude

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Re: 1971 Johnson 50ESL71S What do I do?

In its most basic form, the electric shift lube is labeled "type c"
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

I'm also looking for info on which prop I should get. I've seen props that fit with pitches anywhere from 9 all the way up to 21. The prop on it now is a Michigan PJ80 13 3/4 - 15. Would a 17 or 19 get me a little more top end speed? I'm not too worried about holeshot. I wont' be trying to pull skiers or anything. LOL Again, the boat is a 16ft bass tracker with full decking.

Using the Michigan wheel prop finder thing, it comes up with a 17" pitch.
 

eavega

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Re: 1971 Johnson 50ESL71S What do I do?

Well, I've answered one of my questions after scanning through old threads. I didn't know that the ignition has to be on for it to go into neutral.

More than the ignition has to be on. The motor has to actually be spinning. You will be able to hear the shift solenoids click by applying voltage to the correct wires, but the engine won't actually go into neutral until it is turning.

Rgds
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

Pulled the carbs and lower unit this afternoon. The low speed adjusting needles both need to be replaced. The tips of both were bent. Also have to order both exhaust gaskets for the lower unit. They're in pieces. Other than that, no big surprises. No oil leakage from the lower unit. Carbs are dirty and gummed up pretty badly. Fuel filter/pump was surprising clean considering that the gas tank was full of rust and debris.
 

eavega

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Re: 1971 Johnson 50ESL71S What do I do?

I'm also looking for info on which prop I should get. I've seen props that fit with pitches anywhere from 9 all the way up to 21. The prop on it now is a Michigan PJ80 13 3/4 - 15. Would a 17 or 19 get me a little more top end speed? I'm not too worried about holeshot. I wont' be trying to pull skiers or anything. LOL Again, the boat is a 16ft bass tracker with full decking.

Using the Michigan wheel prop finder thing, it comes up with a 17" pitch.

Stick with the 15P so you can at least baseline it on your rig. Many things affect the correct pitch for your setup; boat weight and weight distribution, motor height, trim angle, etc. Get the motor running on the rig first. Then, check that your motor speed is within acceptable limits (I had a 72 50 HP Evinrude, and that one was rated to 6000 max RPM). If its close, make the adjustments that don't cost anything i.e. verify the correct motor height and trim angle (if you have manual trim like mine did, you don't get the luxury of playing with the trim angle while underway), and verify that the boat's weight is as expected and not super heavy due to water under the deck or in the flotation foam. Once you have all those problems verified and/or corrected, then use the prop pitch to get your motor running at the right WOT speed.
For the record, my 50 HP Evinrude needed a 13P prop to move my 15' fiberglass trihull properly. Someone had undertaken a rebuild of the boat, and had used heavy-duty plywood everywhere, thus making the boat over 100 Lbs heavier than it should've been. Pair that with the boat being under-powered to begin with (rated for 70 HP, so the 50 HP was barely acceptable). The 50 would move my boat at about 28 MPH by GPS with the 13P prop. It would just not get above 4800 RPM with the 17P prop that it came with, and would not plane the boat out.

Rgds
 

bustednuckls

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Re: 1971 Johnson 50ESL71S What do I do?

I had the exact same motor. Got it from a friend dirt cheap, with no spark. He gave me a book on it and done all the tests in the book. The stator was weak but not bad, turned out to be the trigger coil. I ordered a new one from Iboats and it was up and running like a champ. If it goes into gear when the engine is cut, I believe that means a bad shift solenoid according to the manual... Good luck and happy fishing
 

halfmoa

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Re: 1971 Johnson 50ESL71S What do I do?

Get it running before you purchase a prop! You don't want a $300 prop on a piece of scrap metal!
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

I am going to wait till I get it running before buying the prop. Also want to see how it runs with the 15 pitch before I get another. I am going to need another one though. The lower unit on this thing will be way too expensive to rebuild if a bad prop ruins the bearings/gears.

There is a tach on the console, but it's not hooked up to anything. How do I check the rpms?

Parts will be in Thursday, so I should know if it's going to run or not by Friday. Fingers crossed.
 

eavega

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Re: 1971 Johnson 50ESL71S What do I do?

I am going to wait till I get it running before buying the prop. Also want to see how it runs with the 15 pitch before I get another. I am going to need another one though. The lower unit on this thing will be way too expensive to rebuild if a bad prop ruins the bearings/gears.

There is a tach on the console, but it's not hooked up to anything. How do I check the rpms?

Parts will be in Thursday, so I should know if it's going to run or not by Friday. Fingers crossed.

Tach should have three connectors; power, ground, and pulse or signal. Inside the control there should be a grey wire. If the tach has never been hooked up, then it will simply have a rubber boot on the end. The grey wire is your signal. Other than that its power and ground, and all three should be marked. make sure the tach is set to 6p.

Rgds
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

I'll have to look into it. There is a bundle of wires hanging from the remote housing. Haven't looked at them too carefully, but I'm pretty sure one was grey and one was white with orange stripe. The tach has two short wires hanging from it that have been cut, one yellow and one brown or black. Can't remember for sure.
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

Some of my parts came in today. I got the carbs rebuilt, stator, coils, and water pump installed. Just waiting on the low speed needles, spark plugs, and some gaskets to get it all put back together so I can try to fire it up.

Here's some pics of the wires from the remote and the tach. There are 4 wires coming from the remote. Two that are white w/orange stripe, and two that are grey. The grey ones are joined together.
 

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FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

The rest of my parts should be in today, so I should know if it's going to run or not by this afternoon. Still need to figure out how to wire the tach. Also found a local boat shop with a brand new 15 pitch prop he'll let me have for a steal. That is, if I end up deciding to stay with the 15 pitch.

According to these instructions I found for the tach that is on the console, the yellow wire is the signal, and the black is the ground. There is no 12v + wire or connection.
http://www.classicboatwork.com/clas...ons/Airguide 653 Instructions Tachometers.pdf
So my issue now is, which grey wire do I attach to the yellow wire, and do I connect the black wire to one of the white/orange stripe wires, or ground it to the battery? Or will this tach not work and do I need to buy a new one?
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

After looking the tach over very closely, I found that it is an AirGuide model 661.

From the instructions for other airguide models, I know that the yellow wire is pulse signal, and the black is ground. What's stumping me is the two grey wires and the two white/orange wires.

The rest of my parts are out for delivery and I can't sit still. I want to get this thing put back together and running!
 

FISTer

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Re: 1971 Johnson 50ESL71S What do I do?

Parts showed up. Let's just say that the tach is the last thing I'm worried about now. Got it all put back together... STILL no spark. So I went back to checking all connections and wiring, etc. Noticed a tiny bit of electrical tape on the back of the rectifier/regulator. Immediately though it can't be good. I was right. Peeled off the tape and two of the three wires are frayed. I guess the PO was too lazy and cheap (only about $30) to fix it right. So now I know why the stator was fried. Oh well, guess I get to wait another 4-5 days on another part to come in.

Sorry for the gripe. Just a little frustrated/disappointed. I was really hoping to have this thing running today. I guess the upside is that I haven't wasted any money on parts I didn't need. The stator and coils would have had to be replaced anyway.
 
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