Charging problems in XTR2 car

[PhillB]

Hi,

I have a 1999 hayabusa engine in a Westfield XTR2 car. Used to charge fine but has developed a problem that I can't solve so any thoughts would be great.

If battery is charged externally it holds charge fine and starts the car no problems, but if car is used for say 20 mins the battery is then too flat to stat the engine. Even though the battery goes flat the engine continues to run fine.

Have followed the charging test flow chart and all seemd ok other than the voltage at the battery actualy dropped when the engine was revved rather than rising (from around 13V to 12V), so changed the rectifier/regulator. Now the voltage across the battery when running the engine seems fine. However the battery still goes flat after say 20 mins running.

Have checked the generator output and that is fine from all three windings, and is the same at the rectifier.

If the battery wouldn't charge with a battery charger or didn't hold charge I'd suspect the battery, but as it does it seems the battery is fine, but I could be wrong.

Not really sure what to try next or how to test to find out why the battery is going flat with the engine running. Have read all the other threads I can find but still can't find the problem with mine so any thoughts would be most appreciated as its driving me mad!

Thanks,

Phill.

 

[RussellJ]

So when the engine is on, what voltage do you get on the battery?

 

[PhillB]

From memory around 14V I think. I would check but can't start the car as stripped the started motor splines during a spin and am waiting for the parts to come. Have been trying to find the problem with an avo in the mean time.

 

[RussellJ]

Yeah you should have about 14.6 while running.

Did you do the ohm (engine off) and 65V (engine on) checks on the stator yellow wires and all is good there?

 

[PhillB]

Yes around 0.4ohms between windings and greater than 65V (nearer 80V0 at 5000rpm.

 

[RussellJ]

Yes around 0.4ohms between windings and greater than 65V (nearer 80V0 at 5000rpm.

hmmmmm. Very odd. It would only point to the battery then? Or something draining the system while the bike is on. Short perhaps?

 

[PhillB]

Can't find a short, but that has to be a possibility. Thought I'd hit on the solution as have a resistor that grounds the generator when the battery isolator is switched off, so was sure I was going to find it was still grounding it when on, but checked and its working properly (ie. grounding via the resistor when off but open circuit when on).

Just ordered a new battery as can't think what else to try. Worst case at least I'll have one to use while I'm charging the other!

 

[RussellJ]

Can't find a short, but that has to be a possibility. Thought I'd hit on the solution as have a resistor that grounds the generator when the battery isolator is switched off, so was sure I was going to find it was still grounding it when on, but checked and its working properly (ie. grounding via the resistor when off but open circuit when on).

Just ordered a new battery as can't think what else to try. Worst case at least I'll have one to use while I'm charging the other!

Well good luck.. Tracing wires is going to be a pain

 

[PhillB]

I'll see what the new battery does and then have to think of somethig else if not. Its more of a pain as the car has a custom loom so doesn't conform to normal Hayabusa wireing diagrams.

Thanks for the help,

Phill.

 

[buddha65281]

PhillB, I have the same problem. The bike was putting out 13v at idle and when I revved it up the voltage droped to around 12.5. No matter how high I revved it, it would always drop in V. I bought a R/R and switched it out, now the bike has around 14.8V at idle but same this happens when I rev it up! I have checked everything. If you find something let US know. I am looking at buying a Stator/Generator and seeing if that fixes it. I have checked all the wires and can't find anything wrong. It really bites because after riding for a while if I shut off the bike, the starter wants to drag the battery down. But when it is cold, the bike fires up perfectly.

 

[RussellJ]

It is sopposed to drop. When you sit at idle at about 14.6 the voltage will drop when you revv it. That is normal to drop a coupe points. As long as it isnt anymore than .3 i think. I will have to check to see how much mine drops when revved. Currently under foul weather so I cant right now

 

[PhillB]

PhillB, I have the same problem. The bike was putting out 13v at idle and when I revved it up the voltage droped to around 12.5. No matter how high I revved it, it would always drop in V. I bought a R/R and switched it out, now the bike has around 14.8V at idle but same this happens when I rev it up! I have checked everything. If you find something let US know. I am looking at buying a Stator/Generator and seeing if that fixes it. I have checked all the wires and can't find anything wrong. It really bites because after riding for a while if I shut off the bike, the starter wants to drag the battery down. But when it is cold, the bike fires up perfectly.

Have you tried changing your battery? I will as soon as I'm back from holiday, as can't really think of much else it can be as both ac and dc (since changing the reg/rec) charging voltages seem fine and no shorts or current drains I can find. I'll let you know how I get on.