Bad rectifier, Maybe?

[clemsonfor]

Im 90% sure its dead.

I have a 1990 johnson 150gt. I have had the problem for over a yr now. I just found the pinned thread i think by spinnerbait nut about testing the tach. That tells you to remove the grey wire at the terminal block and hook it to the yellow grey wire at the terminal block going to the stator. If the tach works you have a bad tach if not bad rectifier. I had no tach doing this.

The other reason i think the rectifier is bad is that my charging gauge always just shows 12-13 like the battery volts and the tach wont work. Well it works sometimes or most of the time at startup for a min or 3 max and it charges up to 14 on the gauge, then will drop on the volt meter and tach will quit.

My Real question is do these things just go dead or is it customary for them to do like i have seen and work for a few mins then stop right after startup?

If you dont think its the rectifier positively shoot me another direction.

 

[wilde1j]

Re: Bad rectifier, Maybe?

You need to eliminate the stator before you replace the rectifier. Measure the AC voltage across the yellows to the rectifier at fast idle. If voltage is < 30 VAC, the stator is NG.

You can also test the rectifier diodes with an ohmeter.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

Ok just got back in after running it. Here is what i did and found. This time the tach and charge gauge were working, and worked for the 5 mins or so i was standing there, even after cutting it off and on 3 times (it will never work on the water that long). I put my volt meter on AC and tested (on the terminal block) the voltage between the 2 yellow wires. I was showing like 1500 rpm on the tach and was showing around 25 volts.

Will this change if the tach quits working or does this mean stator is good and rectifier is positively bad. Any more test i can do to help the super experts here?

Edit; I just reread the post and saw you said <30 volts AC the stator is no good. So im guessing this means my stator is no good, but what about the rectifier now, will a bad stator make the tach go out like a rectifier?

Thanks, Nate

 

[wilde1j]

Re: Bad rectifier, Maybe?

The stator may be OK. What RPM was the idle? Did the voltage go up as the throttle was increased? There are additional tests on CDI Electronics website. You will need a DVA adapter. These are expensive parts and you want to be sure before you start replacing.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

This was as a constant 1500rpm. I did not move throttle up or down. I will go to the cdi site. Trust me im asking the questions cause i noticed the rectifier was 180ish and now the stator is like 350ish im not going to throw parts at it!

 

[clemsonfor]

Re: Bad rectifier, Maybe?

Ok after a few other things i did i went to retest it. At about 1000rpms i was getting 15 volts or so and when i run it up to about 2500 rpm to 2000rpm somewhere in there (tach dropped out this time so i could not tell) i was getting 40 volts. So this tells me the Stator is GOOD?

 

[wilde1j]

Re: Bad rectifier, Maybe?

I would assume stator is OK. Do some more testing of rectifier and check all associated wiring for insulation breaks and integrity.

BTW , CDI makes excellent ignition and charging system parts which are less costly than BRP parts.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

I would assume stator is OK. Do some more testing of rectifier and check all associated wiring for insulation breaks and integrity.

BTW , CDI makes excellent ignition and charging system parts which are less costly than BRP parts.

Yea i have used them on my other motor for parts. Im thinking to now that rectifier is bad. I felt better after this latest test of the stator.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

To pull the regulator so i have to pull the flywheel? Or is it that thing near the back on top of the block halfway under the flywheen that looks like you can get to it without pulling it (has to many wires coming out of it i think)?

 

[FarmerSid]

Re: Bad rectifier, Maybe?

It is the part that the two yellow wires go to that you tested the AC voltage at. You tested them at the terminal block. The terminal block fastens down to the reg/rect. At least it does on my 85 120. Don't have to pull flywheel. You do if stator is bad. The power pack is fastened on top of the reg/rect. Don't take this as the gospel as I just changed mine and had to do some poking around to find it. I have a service manual on the way and asked some questions here but found I got very few replies especially with the amount of traffic on this forum. Maybe it's because I'm new. Don't know. Some questions get tons of replies.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

Ok If its under the power pack thats prolly why i did not see it. All the wires are wrapped up so its hadt to see where they go. I could not figure why they would have put it under the flywheel, knew the stator was there though as it needs the magnet off it.

I will look around somemore thanks.

As to the number of replies you get you see you and Wilde1 were the only to respond to it. There are literally thousands of members and prolly hundreds at any one time. I think this is the most active forum i have ever been in. I have read a lot and fixed a lot from here as well no better place as far as im concerned. I have noticed the lack of replies, but i think its due to the traffic has nothing to do with you being new. Think about it when you log on you start at the top. If its been 3 days there literally may be 15 pages since you last logged in you may get through the first 5 then stop. You see i have been here since 2005. But in the last few years i have been problem free or could fix it myself. I know thats its not good i wasent giving back but thats how it was. I think back in 05-06 it was much easier to get replies to your posts there was still a lot of people but i remember JB Tasahsdaddy adn Joe reeves would comment on questions i have had, that seems to not happen as much anymore.

These threads also dont drift like in other forums ive been in, thats good for the searability of them. I guess they go in the talk section to talk?

 

[wilde1j]

Re: Bad rectifier, Maybe?

If in doubt, look at parts list on BRP Evinrude website. TD died last year and Joe and JB are still around, just not daily.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

Oh my god, i had no idea. Im sorry to hear TD died he was a gr8 guy.

I still see the Joe and JB posts from time to time but not as much. I also remember reading you stuff from time to time over the years as i recognize the name. Thanks for your help and time.

TD rest in Peace.

 

[ratkiller]

Re: Bad rectifier, Maybe?

Watching this thread with interest. I have a similar problem with a 1990 GT 150. Tach works intermittently. Runs then drops right off to zero. Then will begin to work again. I'll be interested in what you find wrong.
ratkiller

 

[wilde1j]

Re: Bad rectifier, Maybe?

Watching this thread with interest. I have a similar problem with a 1990 GT 150. Tach works intermittently. Runs then drops right off to zero. Then will begin to work again. I'll be interested in what you find wrong.
ratkiller

Start your own thread if you want help. Don't not hijack this thread. Bad form!

 

[emdsapmgr]

Re: Bad rectifier, Maybe?

Tachs do go bad, but not that often. In your case, it's probably not the tach, since two problems show up at the same time. No tach and low volts on the the gauge. Normally, the combination rectifier/regulator will permit volts to creep up to 13.5+ volts or so after running for a while. Likely the combination regulator/rectifier may be bad. That engine has the high output 35 amp charging system with the vented flywheel. This is a powerful system needs to be in tip top shape. If the regulator is the culprit, I'd get it serviced/changed soon. When they go bad, they are known to catch on fire due to the high current loads.

 

[clemsonfor]

Re: Bad rectifier, Maybe?

This is a powerful system needs to be in tip top shape. If the regulator is the culprit, I'd get it serviced/changed soon. When they go bad, they are known to catch on fire due to the high current loads.

!!!!! WOWW i did not know there could be that problem if i ran it. I will increase my search intensity for parts!!