Fan current?

[davidon]

Is there any way to lessen the current draw from the fan? I just got back from an Art museum in town and as soon as I got there and traffic slowed to stop and go and I could see the volts going down as the fan went on. As mentioned before I konked out at Thunder under similar conditions and am a bit nervous that it will happen again. May have to put in a headlight switch to turn it off when the fan goes on..but other than that anything else to do? Is this due to an old harness overall? I don't have any other electronics to drain the system.

On a side note ...gotta get to the museum more often...hot chicks a plenty..could'nt believe the body on one of them...:biglaugh:

 

[Rhoy Carter]

A better rectifier regulator will help. I put a late model RR from Python on my 85 and a headlight cutoff switch now Im getting 13.5 volts with headlight and fan running.

 

[Buster Hymen]

I agree with above. The problem isn't the fan, it is your charging system is not working properly.

 

[davidon]

As I said before...Odyssey battery, R1 R/R, upgraded Venture stator, crimp fix, heavy duty ground kit, everything soldered...If its the charging system I'd like to know where to look..this only happens under hot conditions. I would suspect the R/R as the only possiblilty since it was a used unit but i assumed it either works or does'nt. Is this correct or can you have gradual failure?

 

[Miles Long]

As I said before...Odyssey battery, R1 R/R, upgraded Venture stator, crimp fix, heavy duty ground kit, everything soldered...If its the charging system I'd like to know where to look..this only happens under hot conditions. I would suspect the R/R as the only possiblilty since it was a used unit but i assumed it either works or does'nt. Is this correct or can you have gradual failure?

So you've done all of the above - and you obviously have an on-board voltmeter - so what is the actual voltage when the bike is stopped at a light, idling, and after been driven for a while to (supposingly) charge the battery? Remember, at idling speeds it will be the battery voltage that will support the current draw of the bike, including the fan, so the battery must be in a healthy state of charge.
And what is the voltmeter reading at "charging" rpm's - say 4500 and above? Should be 14 + volts. A properly operating RR will keep it below 15 volts.
If all appears to be O.K., don't assume the battery is good, because it is new. Have it tested at a retailer. Even a defective battery can appear to be holding a charge, but can rapidly deplete when put under a loaded condition. No "staying power", so to speak. Let us know what your numbers are . Cheers, Miles

 

[davidon]

So you've done all of the above - and you obviously have an on-board voltmeter - so what is the actual voltage when the bike is stopped at a light, idling, and after been driven for a while to (supposingly) charge the battery? Remember, at idling speeds it will be the battery voltage that will support the current draw of the bike, including the fan, so the battery must be in a healthy state of charge.
And what is the voltmeter reading at "charging" rpm's - say 4500 and above? Should be 14 + volts. A properly operating RR will keep it below 15 volts.
If all appears to be O.K., don't assume the battery is good, because it is new. Have it tested at a retailer. Even a defective battery can appear to be holding a charge, but can rapidly deplete when put under a loaded condition. No "staying power", so to speak. Let us know what your numbers are . Cheers, Miles

If not hot its at 14V at idle and at crusing speed..when hot, idling and fan kicked in was starting to dip into the mid 12 range. The longer the idle time the lower the dip starts to go (or so i think..will have to test this). How long should battery power hold out with fan on?

 

[Miles Long]

13+ volts is normal when at idle. If only in the mid twelves or lower voltage when idling, light and fan on, this would indicate that the stator/RR is not supplying enough amperage. Did you have the Venture stator and R1 regulator tested, following installation? I don't know the capacity of a Venture stator, but a 1990-on V Max stator should supply 14 volts, 22.5 amps @ 5000 rpm (as per Clymer manual) The Venture stator should be putting out more amperage.
I would leave the testing to a qualified automotive or bike electrician.
If the charging voltage and amperage proves to be O.K., and the battery tests good, then the problem would be too much amperage draw, caused by defective components or wiring, just as you thought in your original post. But eliminate the causes systematically, starting with the stator. There is an excellent electrical fault-finding chart that has been mentioned in some previous posts. Perhaps someone can supply a link to it? Good luck! Miles

 

[davidon]

So you've done all of the above - and you obviously have an on-board voltmeter - so what is the actual voltage when the bike is stopped at a light, idling, and after been driven for a while to (supposingly) charge the battery? Remember, at idling speeds it will be the battery voltage that will support the current draw of the bike, including the fan, so the battery must be in a healthy state of charge.
And what is the voltmeter reading at "charging" rpm's - say 4500 and above? Should be 14 + volts. A properly operating RR will keep it below 15 volts.
If all appears to be O.K., don't assume the battery is good, because it is new. Have it tested at a retailer. Even a defective battery can appear to be holding a charge, but can rapidly deplete when put under a loaded condition. No "staying power", so to speak. Let us know what your numbers are . Cheers, Miles

Just got back from Batteries plus...batt checks out OK..I did see on the way back from there the Volts at speed was 13.5 vs 14 when engine is not warmed up. Does stator amps drop when hot? I'm going to test stator and R/R now. Also anyone know if idle setting also changes in warmer weather? Noticed idle dropped below 1000 now.

 

[RagingMain]

Just got back from Batteries plus...batt checks out OK..I did see on the way back from there the Volts at speed was 13.5 vs 14 when engine is not warmed up. Does stator amps drop when hot? I'm going to test stator and R/R now. Also anyone know if idle setting also changes in warmer weather? Noticed idle dropped below 1000 now.

Yes all electrical things are effected by heat. It will show a difference

Easiest way to tell the current draw is to use the following equation

V=IxR

Measure the resistance of the fan using a voltmeter across the terminals and divid that into what every voltage is reading 13.5 or 14.
THat will give you the current of that circuit.

 

[Miles Long]

Just got back from Batteries plus...batt checks out OK..I did see on the way back from there the Volts at speed was 13.5 vs 14 when engine is not warmed up. Does stator amps drop when hot? I'm going to test stator and R/R now. Also anyone know if idle setting also changes in warmer weather? Noticed idle dropped below 1000 now.

You are on the right path, Mr. Davidon. One step at a time! If the stator/RR is sending enough juice to your battery at charging rpm's and both under cold AND hot operating temps , then determine the culprit circuit that's causing you grief. One or more of these is drawing more amperage than designed, because of component or wiring problems. You can check each circuit individually using an ammeter. You can also test for short circuits in the wiring or connections with an ammeter, by doing a battery leakage test. But be careful with these tests, you can get shocked, and/or fry your test equipment if done wrong! I'm lucky myself - I have a friend that's an electrical tech, all this stuff is second nature to him. Works cheap too. No money, just beer! Miles

 

[davidon]

Alright I think it was the connections from the stator to R/R block ...seemed loose and one of the white wire connectors was missing a piece of its tab. Refit new connectors, soldered and reconnected. With fan on now getting 13.5 at idle but this is under non hot conditions. Will ride and retest this week.

 

[Buster Hymen]

OK, I didn't know you had done that much work to your charging system. I'll try and find out how much the fan draws.

 

[RagingMain]

OK, I didn't know you had done that much work to your charging system. I'll try and find out how much the fan draws.

Just measure the resistance of the fan and divide it into the voltage that will tell you the amperage

 

[satariel666]

Just measure the resistance of the fan and divide it into the voltage that will tell you the amperage

Fargo Im afraid this simple Ohm formula wont work with motors.
Current will be higher.

 

[davidon]

Alright I think it was the connections from the stator to R/R block ...seemed loose and one of the white wire connectors was missing a piece of its tab. Refit new connectors, soldered and reconnected. With fan on now getting 13.5 at idle but this is under non hot conditions. Will ride and retest this week.

Retested and the problem is still there! Back to checking the stator and R/R

 

[desert_max]

But be careful with these tests, you can get shocked, and/or fry your test equipment if done wrong!

A 12VDC circuit will not shock you - even if you're soaking wet.

(Maybe if you're holding onto a bare spark plug boot while using the meter on the charging circuit...)

 

[Miles Long]

A 12VDC circuit will not shock you - even if you're soaking wet.

(Maybe if you're holding onto a bare spark plug boot while using the meter on the charging circuit...)

I was thinking of the test performed at the stator output connection - AC current - I think about 50 volts across any two wires, (for the V-max OEM stator) Miles

 

[davidon]

Had a DOH moment and think I realize my problem now.. PCW mounted my R/R too close to the exhaust. When bike is hot and at idle with no air flow it's cooking it. Gotta move it to the scoop..hopefully before Thunder tomorrow.

 

[satariel666]

Had a DOH moment and think I realize my problem now.. PCW mounted my R/R too close to the exhaust. When bike is hot and at idle with no air flow it's cooking it. Gotta move it to the scoop..hopefully before Thunder tomorrow.

Nice. I would never say that this could couse Your problems :confused2: