GS1000 regulator/rectifier replacement (SH232)

[superawesome]

Hi all,

few weeks ago the (new) battery of my 1978 GS1000 didn't charge anymore. I did posplayr's quicktest to verify, then checked the diodes of the rectifier and found that one of them was dead. As a replacement I tried to get an SH775 (as recommended here in the forum) but they seem to be hardly available in Europe (maybe the lack of Polaris snowmobiles?), the few ebay ones don't seem genuine to me.
I tried silent hektik but they apparently change their products at the moment, so it would have taken at least 4 weeks to get something delivered.

Looking at the list of r/r here in the forum I bought a used SH232-12V from a Honda CB400 shipped from Germany for 25€. With the help of BikeCliff's documents I got all the connectors replaced to fit the GS.


So today was the day of putting it on the bike! Everything went well, the battery seems to be charging. Results of the quicktest are:

Quick Test Steps:

1.) key off................Normal 12.7 volts-12.9 volts 12.7 V

2.) key on (but not cranking with lights for 10 sec).....Normal 12.2-12.5 volts 12.5 V

3.) at idle (1500 rpm).....12.6volts - 13.2volts 14.3 V

4.) at 2500 rpm 13.5 -14.0 volts 14.3 V

5.) at 5000 rpm.....14.0 -15.0 volts 14.3 V

6.) key off.....slightly higher than measurements # 1 (12.8-13.0 v) 12.8 V


At this point many thanks for the great guidance (documentation) in finding the issue (posplayr) and fixing it (BikeCliff)!!!

So it seems to be charging, which gave me a first feel of relaxation At second thought (and re-doing the quick test), the charging curve seems a bit steep to me. It only goes below 14V at rpm lower than 1000 (idle speed is ~1500), I measured approx. 13.8V @ 1000 rpm.
The SH232 has a sense wire that I attached to the rear brake light wire (green-orange one). Between that and battery - I measured only 11.9V, while measuring the battery was about 12.7V. So I guess the sense wire makes the voltage go up.

However, as my experience and knowledge is limited I guess there are some people here that can tell me if this is nonsense or not.
Is 14.3V starting >1000rpm something to worry about?

Thanks for your insights
Juergen

 

[superawesome]

One more thing that comes to mind:

As the new SH232 is bigger than the old regulator, it nearly touches some plastic parts (see picture).
How hot do those things get? Might it melt the plastic?

 

[posplayr]

Hi all,

few weeks ago the (new) battery of my 1978 GS1000 didn't charge anymore. I did posplayr's quicktest to verify, then checked the diodes of the rectifier and found that one of them was dead. As a replacement I tried to get an SH775 (as recommended here in the forum) but they seem to be hardly available in Europe (maybe the lack of Polaris snowmobiles?), the few ebay ones don't seem genuine to me.
I tried silent hektik but they apparently change their products at the moment, so it would have taken at least 4 weeks to get something delivered.

Looking at the list of r/r here in the forum I bought a used SH232-12V from a Honda CB400 shipped from Germany for 25€. With the help of BikeCliff's documents I got all the connectors replaced to fit the GS.
View attachment 52686

So today was the day of putting it on the bike! Everything went well, the battery seems to be charging. Results of the quicktest are:

Quick Test Steps:

1.) key off................Normal 12.7 volts-12.9 volts 12.7 V

2.) key on (but not cranking with lights for 10 sec).....Normal 12.2-12.5 volts 12.5 V

3.) at idle (1500 rpm).....12.6volts - 13.2volts 14.3 V

4.) at 2500 rpm 13.5 -14.0 volts 14.3 V

5.) at 5000 rpm.....14.0 -15.0 volts 14.3 V

6.) key off.....slightly higher than measurements # 1 (12.8-13.0 v) 12.8 V


At this point many thanks for the great guidance (documentation) in finding the issue (posplayr) and fixing it (BikeCliff)!!!

So it seems to be charging, which gave me a first feel of relaxation At second thought (and re-doing the quick test), the charging curve seems a bit steep to me. It only goes below 14V at rpm lower than 1000 (idle speed is ~1500), I measured approx. 13.8V @ 1000 rpm.
The SH232 has a sense wire that I attached to the rear brake light wire (green-orange one). Between that and battery - I measured only 11.9V, while measuring the battery was about 12.7V. So I guess the sense wire makes the voltage go up.

However, as my experience and knowledge is limited I guess there are some people here that can tell me if this is nonsense or not.
Is 14.3V starting >1000rpm something to worry about?

Thanks for your insights
Juergen

Your numbers look good although as you have observed, you get an unusually high out put at only 1000 RPM. The 13.8v at 1000 RPM is more reassuring but still indicated higher than normal charging. It is curious but not anything to be particularly worried about.

As far as the sense wire, yes, you should be able to adjust the output charging voltage somewhat by changing that "sensed" voltage. Since this looks like a newer R/R, you might use your DVM (digital volt meter)on amps to measure the leakage current when the bike is off but the sense wire is connected directly to the battery (+). If it is on the order of 1-2mA (2mA is 1.3 Amp-Hr in 4 weeks) then you can connect it direct to the battery and get the best sensing point. If it is higher like 50 mA then it will tend to drain you battery over a period of about 2 weeks (50mA is 25 Amp-hr in 2 weeks). The typical GS battery is 14 Amp hour of which you don't want it below 50% state of charge.

 

[posplayr]

One more thing that comes to mind:

As the new SH232 is bigger than the old regulator, it nearly touches some plastic parts (see picture).
How hot do those things get? Might it melt the plastic?
View attachment 52687

It should not get above about 125 degF. Basically if you can't touch it comfortably, it is probably not doing your stator much good.

 

[superawesome]

I measured again and did not have any leakage current this time. Maybe I did something wrong the first time?! However, I will check the charging voltage again when the bike is ready for the road (fighting with the petcock at the moment). Many thanks so far!

 

[tom203]

I used a SH-232 before I switched to the sh-775 series unit. I had mine connected to battery positive.The sense current draw was really low--about .002 amps when bike was off.

 

[superawesome]

Hi all,

my SH232 r/r is still working and all is good at the moment.

However, I have wired the (-) of the r/r directly to the negative terminal of the battery. I have read in some posts that a single point ground is preferred over this for a number of reasons (and since jdvorchak saved me from wasting my time on the oil pan, I can come back to this issue right now ).

Here is a picture of the current setup on my GS1000:
View attachment 53654

The green r/r wire goes directly to battery (-) while the B/W wire goes (via harness) to the frame ground near the airbox.

I checked posplayr's sticky note (charging system health) and I think for me it comes down to three things:
- connect r/r's ground wire to SPG instead of battery (-) (cut wire to be as short as possible)
- make direct connection between negative battery terminal and SPG
- connect airbox frame mount to SPG (already in place)

Anything I missed here?

Thanks
Juergen

 

[hannibal]

You have three out of four. The B/W wire from the harness should also go to the SPG instead of the frame ground.

The only other ground should be from the engine case to the battery (-) to ground the starter.

 

[superawesome]

You have three out of four. The B/W wire from the harness should also go to the SPG instead of the frame ground.

True, that makes it single point ground

The only other ground should be from the engine case to the battery (-) to ground the starter.

Should this already be in place (on a stock bike) or do I need to create that as well?

 

[hannibal]

It should be there. It runs from a case bolt on top of the transmission to the battery negative. Not sure if it originally went to the battery box mounting bolt. I mistakenly removed it when I did the SPG. A year later, I fried my frame to SPG wire since it had been carrying all of the starter current through a tiny wire.

Actually, I see this ground listed in the GS 750 parts diagram but not the 1000. I imagine it should have one but I have no experience with the bigger bike.

 

[superawesome]

It should be there. It runs from a case bolt on top of the transmission to the battery negative.

I found it, the black wire disappears somewhere in the harness. Guess that should be ok.

I did the SPG now, I have four connections:
1. from the SPG to battery negative
2. R/R to SPG
3+4. 2 B/W to the harness

Sound about right?

 

[superawesome]

I did the SPG now, I have four connections:
1. from the SPG to battery negative
2. R/R to SPG
3+4. 2 B/W to the harness

On second thought, I think it should be like this:
1. from the SPG to battery negative
2. R/R to SPG
3. B/W to the harness
4. B/W to the frame (airbox/battery bolt)

 

[Grimly]

As a replacement I tried to get an SH775 (as recommended here in the forum) but they seem to be hardly available in Europe

http://www.polaris.com/select-country

For example, for me, there's a couple reasonably close to hand. It's not snowmobiles but ATVs they sell here.
The prices of the regulators have gone up in recent months, though. I suspect the bean counters at Polaris realised they were selling far more spares than could ever be accounted for by the normal number of ATVs they'd sold, and decided to charge what the market will bear.

Can't find any in Switzerland, sorry.
http://polarisgermany.de/handler-finden/karte/