Johnson 60ESL70B component

[phoenix1151]

The wiring diagram for this motor shows a component named "diode assembly" and I have one on my motor, not to be confused with a "clipper circuit assembly" (that my model "B" doesn't use) or the blocking diode in the remote control. What purpose is this component? It seems to be exclusively to power the shift solenoids? It is fed by the same stator wires as the rectifier and leads to the shift switch whereas the rectifier leads back to the battery for charging purposes and powering motor operation. What is the output of this "diode assembly", 12 VDC? It must be rectified as well?

 

[phoenix1151]

OK, it looks like it is named "diode and lead assembly" on the exploded parts diagram, but other verification questions remain for me.

 

[racerone]

Elegantly simple.-----Blocking diode keeps lower unit in neutral using current from alternator.-----Prevents it slamming into forward when turning key to --OFF---at high revs it could do damage.-----Why the question ?

 

[phoenix1151]

I wasn't asking about the blocking diode (0279176) in the remote, I was asking about the "diode assembly" as it is called on the wiring diagram or might be called "diode and lead assembly" (0383840). I presume the output is 12VDC so it must be rectified and regulated like the formal "rectifier" (0580795) but I do think it is to specifically provide power for the shift solenoids through the shift switch.

Anyway, what lead me to it was I'm resurrecting the 60ESL70B that hasn't seen water in over 10 years. I've replaced the impeller, start solenoid, ignition switch in the remote and cleaned the carbs (reeds looked ok). I went to check battery charging but the voltmeter I had on the battery went haywire when the motor ran, so I figured the rectifier was kaput, so checked it and the diode assembly which made me wonder about the diode assembly's specific function, that's all.

Many years ago, a marine mechanic changed things to use an automotive coil in place of OEM components, but it runs, sort of. I may have to adjust the slow speed needles on the carbs and check timing. Today, I pretty much had to keep the start lever on the remote near full start position to keep it going (that advances the spark timing does it not)?

 

[jimmbo]

For the first 75-80% of the Throttle Lever, and all of the Warm Up Lever, all that is changing is the Spark Timing.

Is it firing on all Cylinders?

 

[phoenix1151]

Thanks, that what I thought. Yes all plugs confirmed firing with a visual spark tester tool. I cleaned up the insides of the remote and applied a bit of grease to the roller but haven't examined the engine cable adjustments yet.

 

[F_R]

To clarify, the blocking diode supplies power to the shift switch when key is in run or start position. But when key is turned off power to the shift is lost and the shift instantly defaults to forward gear with an unmistakable jolt. Basically, harmless but rather un-nerving. Enter the "diode and lead assembly", which continue feeding power to the shift switch until the alternator coasts to a stop. But why the "blocking diode? Why not just a pliain wire? Because the power coming from the coasting alternator would be fed back to the ignition switch and the motor would not stop. The blocking diode prevents that back feed.

Neither has anything to do with the running problem.

BTW, I am aware of the mod some have made by using a car coil and condenser. But I have yet to hear a report of it being successful.

 

[phoenix1151]

Thanks F_R for that explanation, that is exactly how I interpreted things from the wiring diagram. I was aware of the default in forward gear. I'm wary of the automotive coil usage too but that's for another day if/when it fails, lol. I'm awaiting a new rectifier before moving on with the resurrection.

 

[phoenix1151]

I drafted the following beautiful prose ready to post it, about the 12 VDC circuit going haywire when the motor ran, but then I thought of a comment I had heard about "earth grounding the motor" which typically happens through the lower unit being in the lake. Since I was running it in a plastic barrel with garden hose rubber "ears" on the water intake, I decided to pound a stake in the ground and hook the motor ground to it with a jumper cable. Well, to my pleasant 'surprise', the haywire VDC readings steadied right down. I've seen numerous driveway videos of people running with hose ears but they don't mention grounding the motor. It didn't stop the engine from running without the "earth ground" but surely it can't be healthy for the VDC circuit and components. Comments?

Anyway, yesterday I put in a new rectifier but still got the VDC meter on the 12 volt circuit going haywire when the engine ran. I disconnected the high tension lead from the automotive coil (2.4 ohm) with ballast resistor (1.8 ohm) used in lieu of OEM components and then got a steady 9.5 VDC from the rectifier and 8.8 VDC from the diode assembly during cranking. I was sure those values would increase at running RPM's.

I was hoping to not have to go under the flywheel but it looked like I would have to in order to visually check the stator, etc. I got 4 ohms on the YEL-YEL/GRY stator wires with no continuity to ground so it seemed to check out but I suspected something amok under the flywheel. OEM specs show a 9 amp stator 0580744 for this motor. However, solving my issue with the "earth ground", I'll concentrate on setting low speed needles and timing for now.

PS: A bit more background: the boat was put aside many years ago when it overheated and cut out. This resurrection started with replacing the thermostat, head gasket (blown) and water jacket gasket, then other parts previously mentioned in post #4. I've also put in a temporary cooling water telltale from the threaded port on the top of the engine and am inclined to retain it permanently (throttled to reduced the telltale flow) for visual peace of mind even if it slows the warm-up of the head. I presume that port is upstream of the thermostat since it ejects water right after start-up? What is the internal routing for cooling water?

 

[phoenix1151]

My limited online research suggests timing settings of +4 ATDC at idle and -20 BTDC at full throttle. I don't have access to the appropriate manual for the 60ESL70B, so looking for confirmation.

 

[jimmbo]

There is no Timing Spec for Idle. The Retardation of the Timing is what determines the Idle Speed, and there is no hard fast setting, as it will vary depending on the load on the engine. Adding or removing Pitch at the Prop, will affect where the Timing needs to be to get the correct Idle Speed
The Carbs are Fully Closed at idle, and remain closed, until the Primary Pickup. The Speed Control Section deals with setting this, and the next page shows a Timing Check

Max Timing on a 1970 60hp is 22 degrees BTDC

 

[racerone]

You must pull the flywheel off !----Need to clean / set breaker points at 0.010"----Inspect anti-reversing spring.----Clean rotor and distributor cap.----And 4 ohm on the stator does not sound correct.

 

[phoenix1151]

jimmbo, thanks for that info, can you provide a larger scale version of the pics or PDF file, they becomes illegible when enlarging.
racerone, thanks for the advice, I was hoping to avoid that for now but I guess I'll have to. Do you know the torque for the flywheel nut when reassembling?

 

[racerone]

Tork is 102.5 FT-LBS.----Wasting your time if you do not pull the flywheel off.

 

[jimmbo]

jimmbo, thanks for that info, can you provide a larger scale version of the pics or PDF file, they becomes illegible when enlarging.

That's odd. I click on them twice, and they are very clear.

 

[phoenix1151]

OK, sorry jimmbo, I got them printed.