JMVintage
Just got it firing!
- Joined
- Jul 14, 2009
- Messages
- 18
After reading about some problems with alternator output, some time ago (900Km ago) I installed a voltmeter on my Vintage. Lucky me!
From the first time I had it installed I found very weird that with engine stopped it showed a little bit below 12v (correct) but while riding it showed a load of 15v and with the fog lights ON it showed 13.5V
I asked the dealer who installed it and he said he had compared with a professional voltmeter and that the readings were accurate and normal. I didn’t find a load of 15v normal but I took his word for it.
Yesterday I was riding on the motorway and suddenly I saw the load drop to 10v, then 9v. I decided to stop and check it out. When I switched the ignition ON I noticed I only had 10v on the battery. Miraculously I managed to start the engine and immediately I called my dealer who was kind enough to pick-up the phone on a Sunday afternoon. He said that, if the engine was running I could carry on till home and load the battery later. Fortunately I didn’t take is advice because I thought that an EFI engine needs electrical power to run. I let the engine running for less than a minute and I noticed the voltage dropping. When it reached 8v (minimum readout) the engine stopped (obviously).
Next I checked the Fuse box and I found that F1=30A “Battery Recharger” was so badly burned that it even melted the plastic top.
I replaced the fuse and managed to push start the bike (alone!)
Afterwards while ridding the voltmeter showed 12.5v at any range and 12v with the fog lights ON.
When I arrived home 45 minutes later (80Km) I stopped the engine and the battery showed 11.5v. I tried and started the engine again normally.
My questions are:
- Why was the alternator previously loading at 15v (too high) and now at 12.5v (a bit low)?
- Has the battery been damaged?
- Shall I have the alternator checked?
Thanks for your help.
From the first time I had it installed I found very weird that with engine stopped it showed a little bit below 12v (correct) but while riding it showed a load of 15v and with the fog lights ON it showed 13.5V
I asked the dealer who installed it and he said he had compared with a professional voltmeter and that the readings were accurate and normal. I didn’t find a load of 15v normal but I took his word for it.
Yesterday I was riding on the motorway and suddenly I saw the load drop to 10v, then 9v. I decided to stop and check it out. When I switched the ignition ON I noticed I only had 10v on the battery. Miraculously I managed to start the engine and immediately I called my dealer who was kind enough to pick-up the phone on a Sunday afternoon. He said that, if the engine was running I could carry on till home and load the battery later. Fortunately I didn’t take is advice because I thought that an EFI engine needs electrical power to run. I let the engine running for less than a minute and I noticed the voltage dropping. When it reached 8v (minimum readout) the engine stopped (obviously).
Next I checked the Fuse box and I found that F1=30A “Battery Recharger” was so badly burned that it even melted the plastic top.
I replaced the fuse and managed to push start the bike (alone!)
Afterwards while ridding the voltmeter showed 12.5v at any range and 12v with the fog lights ON.
When I arrived home 45 minutes later (80Km) I stopped the engine and the battery showed 11.5v. I tried and started the engine again normally.
My questions are:
- Why was the alternator previously loading at 15v (too high) and now at 12.5v (a bit low)?
- Has the battery been damaged?
- Shall I have the alternator checked?
Thanks for your help.