1986 70hp johnson overcharging

[sickboy]

I just finished rebuilding my dash in my bass boat with all new digital gauges. When I fired it up on the muffs for the first te tonight, I was watching the voltage gauge.
Without the motor running it was reading 12.4

Started the motor and I was @ 13.4 slowly climbing without revving the motor.
I saw it hit 14.4 and still climbing.

Around 15 volts, all the digital gauges started glitching so I shut it down. I restarted the motor and the exact same readings and rate of climb happened again.

It's safe to assume the glitch was because at 15 vlts the gauges were trying to protect themselves.

My question is, what the hell is going on? I've been reading the service manual and nothing talks about overcharge scenarios, only under charge.

 

[boobie]

Re: 1986 70hp johnson overcharging

The 15-17 volts is normal on that motor. It doesn't have a voltage regulator. Just a rectifier. Your gauges may be designed for a motor with a regulator.

 

[sickboy]

Re: 1986 70hp johnson overcharging

Can a voltage regulator be added easily?

 

[boobie]

Re: 1986 70hp johnson overcharging

Check other posts on here. I know they're out there. OMC used to have one, part # 173640.

 

[sickboy]

Re: 1986 70hp johnson overcharging

I did see a thread discussing that p/n but that part is for a 4 & 6 cylinder. It won't matter going on a 3?

 

[Bosunsmate]

Re: 1986 70hp johnson overcharging

Interestng boat panel, thatd keep my eyes off where i was actually driving.
Looks like an f16 setup
A voltage regulator can always be added into a circuit, my car has one, radioshack or the likes should be able to get you a good 14v one

 

[J JACKSON]

Re: 1986 70hp johnson overcharging

i would check the manufacture but most gauges will work at that voltage i would double check your wiring especially the grounds

 

[sickboy]

Re: 1986 70hp johnson overcharging

The wiring is solid. I just redid everything. I ran a new 8 gauge pos and neg feed from the battery up to the console where they go into terminal strips. The pos goes to the master switch then into the terminal strip.

The manufacture says the gauge reads 0-15 volts. It's right at 15 when all the gauges start franking out. So somehow I need to limit it to under 15 volts.

 

[Faztbullet]

Re: 1986 70hp johnson overcharging

CDI has a direct replacment with built in regulator.

 

[sickboy]

Re: 1986 70hp johnson overcharging

Thanks I will look into that. Is it a replacement rectifier that has a voltage regulator built in? I'm just a bit confused to what the replacement part would be replacing if my motor dosnt have a regulator to begin with.

 

[sickboy]

Re: 1986 70hp johnson overcharging

I think this is the one. Johnson / Evinrude Regulated Rectifier: 193-3408

 

[boobie]

Re: 1986 70hp johnson overcharging

I'd give the one from CDI a try.

 

[sickboy]

Re: 1986 70hp johnson overcharging

Definatly, found it for $70 online. I'll post back with a update. But I figure if this dosnt fix all the problems 100% I can add a small regulator at the panel to protect the guages.

 

[Faztbullet]

Re: 1986 70hp johnson overcharging

Thats it.......

 

[sickboy]

Re: 1986 70hp johnson overcharging

Different question:
When running the motor the other day with the muffs on, after a few minutes the water stream just quit. The water pump has 2 seasons on it. Is it common for a pump to just quit? I thought it may be a thermostat but my motor is slightly different than the schematic in the book. The book shows a thermostat above a pressure relief valve both under the same cover, however I have a smaller cover and it only has a pressure relief valve under it.

 

[Bosunsmate]

Re: 1986 70hp johnson overcharging

Different question:
When running the motor the other day with the muffs on, after a few minutes the water stream just quit. The water pump has 2 seasons on it. Is it common for a pump to just quit?

no.

 

[sickboy]

Re: 1986 70hp johnson overcharging

I also noticed some water coming out above the lower unit and also at the top of the mid section? I didn't see anything in the service manual about servicing up in there. What hell is going on? I will try to take a video tomorrow.

 

[sickboy]

Re: 1986 70hp johnson overcharging

This is the pressure relief valve with no place for a thermostat. Not really sure what the. Purpose of this part is for. The manual shows this and a thermostat but it's not the case.

 

[sickboy]

Re: 1986 70hp johnson overcharging

Read thru the message boards and someone said to poke the telltail nozzle with something thin. Fixed the problem, just was clogged a bit

 

[boobie]

Re: 1986 70hp johnson overcharging

In pic # 1, that is the thermostat. It's got a vernatherm inside of it. Your manual is wrong.