Johnson 70EL76D Looper Terminal Block Wiring

[Slab Slayer]

I have a '76 Johnson 70HP (70EL76D) that I inherited. It has been running for years with only a slight hesitation on WOT from neutral. Last season, it got worse to the point that the hesitation was permanent and it would not achieve more than 6 or 7 mph. I replaced the plugs and all 3 coils with CDI replacements in the offseason. This season, it began with the same. It would run cold off the dock, but once warmed up, it just wouldn't pull itself out of the water. I took it to one.of the last remaining mechanics who would work on it and was told it had a blown power pack and one of the new CDI Coils was bad. He replaced both with used OEM. It ran better, but was still sick. After two outings it again wouldn't achieve more than a slow troll. I have pulled the flywheel, stator and timing ring look good. Replaced the power pack and all 3 coils with Johnson OEM New parts. When I was checking the wiring harnesses for possible rub shorts, I noticed a discrepancy in the Terminal Block Wiring. Not sure if it has always been this way or if my mechanic had some reason to change it. I tend to believe it has always been that way but the looks of it.

In the Seloc '73-'91 Johnson Outboards Repair Manual, Appendix p. A-18, it illustrates the yellow\gray wire from the Stator connected to Terminal 2 with the Gray wire from the Remote Control Assembly. However, on my Terminal Block, this wire is connected on Terminal 3 with the Yellow\Gray wire from the Rectifier & Lead Assembly.

Should I move it? Is this a normal variation in the wiring? What issues would present if left this way? Could that be a part of the problem? What might happen if I move it?

 

[racerone]

Terminal 2 and 3 are the same connection.----Clearly seen in your picture !!-----But post your actual compression values here.----And is a new water pump impeller installed every 5 years ?-----Tested the overheat horn ?

 

[Slab Slayer]

Terminal 2 and 3 are the same connection.----Clearly seen in your picture !!-----But post your actual compression values here.----And is a new water pump impeller installed every 5 years ?-----Tested the overheat horn ?

Aaahh! I did not even notice the band connecting #2 and #3! Thanks for pointing that out! So that is a non issue. I will have to rerun compression for values, but I did test all 3 and they all tested within a pound or two of each other. Mechanic also tested them and said compression was good.

Motor does not have an overheat horn. But the water pump and lower unit oil was neglected prior to me getting it. I put in a new water pump when this started happening last season, possibly after damage was already done.

 

[stresspoint]

lets start by taking a step back .

the motor was running but had a slight hesitation that got worse after the boat sat, which in turn caused it to not be able to plane out .
? did you see any improvement once you put the new parts IE: plugs , CDI , coils ,etc.
? , what made the "mechanic ' believe it was faulty coil /coils , IE: how did he test them.

a few things here don't add up or you are leaving some info out that may be useful to help do an internet diagnosis .

now that we are back to square #1 , take carbs apart and give them a thorough cleaning and inspection.
replace the old worn out fuel pump with a new OEM one ,""" not a cheap ebay china one """..

compression test .post numbers , if possible a leak down test to determine condition of seals.

use a spark tester and insure you are getting a good solid spark on all cylinders.

this should keep you busy for a bit , when done post up results.

 

[Slab Slayer]

? did you see any improvement once you put the new parts IE: plugs , CDI , coils ,etc.
A> Not enough to be considered a successful fix.

? , what made the "mechanic ' believe it was faulty coil /coils , IE: how did he test them.
A> He stated that he tested the Power Pack and said it failed. I don't know how. He came recommended by the marina for these older motors since no one around here will work on them. Does a lot of older motor work. He said he spark tested the coils & 3 was intermittent. Not sure how he tested. I wasn't there.

I completely cleaned and rebuilt all 3 carbs w\ OEM rebuild kits at the end of last season. Also replaced the fuel pump, although not an OEM, and tested all lines for connection leaks

As soon as I get it back together I am going to do a cold compression test, spark test on all 3, hot compression test, and scope the cylinders.

Thanks for helping!

 

[racerone]

Just learn to test the overheat horn !!----If you have no clue ask.----There was a horn installed in the control box when that fine motor left the factory.----That is why I suggested to test this horn !

 

[Slab Slayer]

Thank you so much @racerone for your so very helpful and informative reply. If I didn't know any better, I would almost believe I was being scolded like a child rather than being helped like an adult. But since you are clearly in more of a helpful mood, I will entertain your reply.

I inherited this boat and motor from a family member who bought it second hand from someone. It is not the original control unit to the motor and neither is original to the boat.
There is no overheat horn or buzzer in the control box assembly. There is a temp sensor on the motor, but grounding it to test It produces nothing because... There is no overheat horn or buzzer in the control box. I have not yet chased all the wires to the control box to find the correct one, if it is even there, to install an overheat horn.

So, now that we have established that I know where the temp sensor is located on the motor, that I know where the overtemp horn should be, and I know how to test them, we can move on with other troubleshooting.

 

[Slab Slayer]

Cold compression test isn't looking so good.

Cyl 1: 82
Cyl 2: 82
Cyl 3: 76

Spark drop test passed on all 3
Spark test was insanely good on all 3. Was bridging a 3\4 inch gap and even jumped my insulated pliers to zap the snot out of me.

looks like she is just old and tired.

> UPDATE: I just went back and pulled the invoice copy from the mechanic. Cyl compression test was 108, 114, 102.

 

[F_R]

See the other forum where you posted the same question.

 

[racerone]

Well ----I cannot see , feel or touch your boat.-----I can only try to educate / teach those who are willing to listen.----The factory control had a waning buzzer !!----And compression should be around 140 PSI.----I will step aside.----Good luck with your project.-----Note ---I started repairing Johnson / Evinrude before that motor was even made !!

 

[Slab Slayer]

Well ----I cannot see , feel or touch your boat.-----I can only try to educate / teach those who are willing to listen.----The factory control had a waning buzzer !!----And compression should be around 140 PSI.----I will step aside.----Good luck with your project.-----Note ---I started repairing Johnson / Evinrude before that motor was even made !!

I wasn't commenting on your knowledge base, your experience, or your expertise, which by the level of your Forum Membership is clearly respectable. My issue was with your cast iron frying pan to the face approach without asking questions first to get a clear understanding of the situation. Just because you are an old grizzled veteran of boat motors doesn't mean you have to act like it. Perhaps less use of the exclamation mark would be more palatable!!!

While this is my first foray into the 2-stroke Boat Motors forum world, it isn't my first rodeo in turning a wrench, rebuilding motors, or being a Community Volunteer on forums. I have just never had the opportunity to deal with many 2 stroke marine motors.

 

[stresspoint]

i don't think any one is scolding you ,
there are knowledgeable people here on this forum that can help you only when you give information relative to the issue you are facing and what steps have already taken to rectified the issue..

it is possible that the over temp warning "" not working "" could be making the motor think it is over heating therefor sending the ECU into limp mode. JAT.

there is no crystal ball on the inter net , we don't know you changed the fuel pump or cleaned and rebuilt the carbs , hence , noting that you was not telling the whole story.

DO A LEAK DOWN TEST , the seals in your motor are 40 years old ,OH , and get rid of that AM china fuel pump before it starts melting.

I'm out

 

[racerone]

There is no ECU on a 1976 model.-----There is no " limp mode " on a 1976 model 70 HP !!

 

[stresspoint]

There is no ECU on a 1976 model.-----There is no " limp mode " on a 1976 model 70 HP !!

my bad i was not concise enough !.
power pack , cut out mode .

 

[racerone]

Overheat horn would sound.---Motor would keep running till it seized.------Up to boat operator to shut the engine off !!

 

[stresspoint]

Overheat horn would sound.---Motor would keep running till it seized.------Up to boat operator to shut the engine off !!

so not like other motors where the motor either goes into limp or shuts down if an over heat happens.
must be I'm so used to working on later high tech motors iv forgotten about how privative things were back in the day.
learn something new each day, what would we do without the internet?.

 

[Slab Slayer]

Thanks again for all the help. I did post these over on the other Marine Engines forum, so if you are also active over there, please excuse the duplication. If some are like me, I tend to stick to a home forum as a Community Volunteer where I am established.

I have scoped the cylinders and was expecting a bit more carnage than I found. But then again, I only have a frame of reference from 4 stroke industrial and automotive. Perhaps these marine 2 strokes are more intolerant. That's where I need an experienced eye.

I have uploaded photos for:

Cyl #1

Cyl #2

Cyl #3

Thanks in advance for your experienced feedback and assessment!

 

[racerone]

Older motors are elegantly simple and do not require $150/ hr factory support !!----So simple and reliable.-----One issue today is that folks have little to no idea how 2 strokes work and how they need to be looked after.

 

[Slab Slayer]

Older motors are elegantly simple and do not require $150/ hr factory support !!----So simple and reliable.-----One issue today is that folks have little to no idea how 2 strokes work and how they need to be looked after.

I agree. My ability for a rebuild is there, but time isn't. I also agree with the lack of knowledge on 2 stroke combustion flow. Like many things, it is knowledge that is dropping from society as high tech advancements are slowly making it obsolete. The tree huggers don't like them much either.

 

[stresspoint]

Older motors are elegantly simple and do not require $150/ hr factory support !!----So simple and reliable.-----One issue today is that folks have little to no idea how 2 strokes work and how they need to be looked after.

ahhh , remember when , ya , i agree the old 2 smokers were reliable and would be almost dead before they would stop .
i had forgotten how simple things were back in the 70s when OPs motor was popular , hence why i posted that something should have stopped the motor with no over temp warning present.

i will admit that it has been some time since i worked on a 70s outboard even although there are several up in the shed in various stages of running condition,(cant even give them away , i should pull a couple and brush up on the technology ).

enough waffling ,back on track ,
OP I'm guessing your bogging / hesitation was caused from a crank seal or a vacuum hose split ,its an old motor and seals dry out and cause leaning.( i cant view your pics for some reason) . there is O rings in the fuel pump that causes all sorts of funny problems / symptoms that pertain to air leaks , the china pumps are known for melting the rubber seals and making the motor act as you describe.
there is also a mesh filter under where the fuel line attaches ( silver finger screw) that is known to rust on the china pumps and cause little to no fuel to flow..