Tachometer/Regulator Question

[cleve]

Haven't posted in a while, but recently bought a 1993 Ranger 365V with a 1993 Fast Strike 150 on it. The tach doesn't work but if you look closely, the needle slightly moves when you turn the key on. I don't see a name on the tach but it appears to be original or quite old either way. I pulled it out of the dash, verified it's getting power with my meter, cleaned all terminals/connections, and turned the pole dial a few times but still nothing. The light doesn't work either. I've ordered a new tach and will return if it ends up being a regulator issue.
My question is, if the regulator/rectifier is bad and not sending a signal to my tach, would that also mean that my starting battery would die as well? Battery was fully charged after taking the boat out for a ride the other day is why I ask.

 

[Chris1956]

If the regulator does not give a signal to the tach, it is likely it is not charging.

It is an easy test. Put a voltmeter on the battery posts, engine off. Read dc voltage. Start engine and set to fast idle. Read voltage again and compare.

Voltage at battery with engine running at fast idle should be higher than voltage with engine off.

 

[cleve]

If the regulator does not give a signal to the tach, it is likely it is not charging.

It is an easy test. Put a voltmeter on the battery posts, engine off. Read dc voltage. Start engine and set to fast idle. Read voltage again and compare.

Voltage at battery with engine running at fast idle should be higher than voltage with engine off.

I haven't tested this yet but I did go out again Thursday and rode about an hour or so. Battery was good and strong and engine fired right up at the ramp when we got back. Would think if it wasn't charging, that wouldn't happen. Hopefully it's the tach itself. My new one should arrive this week.

 

[cleve]

Well, it's not the tach. Hooked up a new one and no signal. Has power, needle moves to zero when turn key on, pole setting on 6, battery fully charged. I'm thinking it's a wire/wiring issue. Can someone tell me some tips on how to narrow it down? Also, the signal wire is white/tan colored not grey like I'm used to seeing. Haven't got under the dash yet to sort where it goes.

 

[Chris1956]

Use an ohmmeter to test the wire between the VR and the tach. Alternatively, test the tach wire at the VR, with engine running on a flusher, for some AC voltage. I would expect only a few volts AC to run the tach, but start on a 100VAC scale so you don't burn out the meter.

However, the voltage test I described will tell you if the VR is working. I would do that test first, especially if you run in saltwater. I had a CDI VR rust out about 3 years after I installed it on my '98 Johnny 150HPV6.

 

[cleve]

Use an ohmmeter to test the wire between the VR and the tach. Alternatively, test the tach wire at the VR, with engine running on a flusher, for some AC voltage. I would expect only a few volts AC to run the tach, but start on a 100VAC scale so you don't burn out the meter.

However, the voltage test I described will tell you if the VR is working. I would do that test first, especially if you run in saltwater. I had a CDI VR rust out about 3 years after I installed it on my '98 Johnny 150HPV6.

Got some time this morning to test battery. It was 11.77 at rest and 11.72 with engine running at high idle. Assume the rectifier is shot or do I need to do the other test? Took a pic of it and I guess it's the water cooled version.

Do I need to get BRP or is there an aftermarket that will work? Also where does the red wire go? I can't tell where it goes but it appears to be spliced and wrapped with electrical tape.

 

[Chris1956]

That looks to be the water cooled voltage regulator. I bought one from CDI or Sierra, and it rusted out in a couple of years use in salt water. Unless the OEM version is prohibitively expensive, I would recommend OEM.

 

[cleve]

That looks to be the water cooled voltage regulator. I bought one from CDI or Sierra, and it rusted out in a couple of years use in salt water. Unless the OEM version is prohibitively expensive, I would recommend OEM.

Got the BRP rectifier installed, new starting battery, wire brushed all terminals, and tightened post nuts down firmly, and tach works now. Thanks for help.
Have had my share of weak/bad batteries over the years and the outboard would barely turn over, but this one spun like a new battery was hooked to it. Yet portable charger showed 40% when I hooked it up, was flashing 'bad battery', and would not charge the battery. Meter showed 11.7 volts at rest which I guess is enough to crank the engine on a 1000 amp cranking battery.

 

[Berdink]

Thanks for posting an update.
I'm intending to wire up a tach and have been watching this thread.

 

[cleve]

Reviving this thread...

Recap:
Water cooled rectifier was bad on my 1993 Johnson 150 Fast Strike. Tach not working and starting battery not charging while engine running. Replaced with BRP rectifier.

Have taken boat out 3 times the last few months since replacing rectifier. Went for a short fishing trip yesterday and tach was working and battery voltage was reading over 14 volts on depthfinder when running to two different fishing spots. When ready to go home, started engine to go back to ramp and tach not working and battery voltage at 12.5 on depthfinder, so apparently rectifier is bad again.

I've read a ton about this and can confirm:
My battery connections are clean and tight with nuts and a wrench (no wing nuts). I do have 4 ring connectors on each post. Engine, NOCO charger, Depthfinder, aftermarket bilge pump.
Rectifier wire connections clean.
Red wire from rectifier to starter stud is clean and tight.
I have not reversed the polarity on the battery.
Starting battery is only a few months old (1000 MCA) and was fully charged.
I don't see any obvious wiring issues. No bubbled insulation, raw wire, burn spots, etc.
The BRP rectifier did not come with the purple wire. I wrapped electrical tape on the connector where purple was on motor side.

Any ideas what root cause is here? Anything else I should check? A $300 rectifier should last more than a few months. Stator/Power pack issue maybe?

 

[Chris1956]

Gee, the watercooled VR on my '98 Johnny 150HP Oceanrunner has the purple and grey wire connected. I am surprised your new VR did not have the purple wire connection. The purple wire usually gives the VR a "sense" of the voltage in the wiring harness, allowing it to charge properly.

The service manual calls for .185 ohms across the yellow and yellow/grey leads to the stator. Maybe that is your issue? Hopefully your ohmmeter is pretty accurate.

The service manual outlines some tests for the VR amperage output, however, you need a load pile (Big A$$ resistor) to load the VR. Since you have a new VR, If you can get it to charge, the total amperage is likely to be fine, IMO.

 

[Crosbyman]

jmho... I realize the VR is a water coold unit but... the stator having 2 yellows would indicate a basic ac stator feeding a full wave rectifier VR. 2 phase full wave VR are a very inexpensive component vs OEM. . if you could consider blocking out the VR openning on the PH with small plate seems you should be able to hook-up an external VR to take up charging duties. I realize most AMAZON type VR have no tach feed but that can be set aside to get you going.
As long as you can mount an external VR securely you chould be good to go .

 

[Mc Tool]

a 35a reg will do . I did google the johnson one and find one for $97 NZ ....so probly 60 bucks US.
If you go the air cooled reg see if you cant mount it near the air intake on the motor cover , or somewhere that it gets a bit of cooling air , and just leave the old one there to block the hole .
Not having a tach aint the end of the world , if your boat is propped correctly its not going to over rev on full throttle

 

[saltchuckmatt]

A quick note, posting an old thread is against tos. A moderator will come by soon and close it.

I suggest making a new post and put a link in it as to what you are comparing it to.

Very common issue in here.

Good luck, Salt out!

 

[cleve]

Talked to my mechanic. I am taking it to him in a few weeks for him to look at. He says he'd bet it needs a stator if it's never been replaced, but he's going to check it out.