charging problems!

[sethbrown]

hi all,

ive found that my battery is not charging the battery itself is fine however when the bike is running it is only draining power and not charging.

the rectifier was changed recently and i have done the basic tests but am at a bit of a loss if anyone can shed any light on this it would be much appreciated.

thanks

seth

[Evilchicken0]

When you charge the battery it should have about 13v when you measure across the terminals.
Install the battery and again measure across the terminals, if it drops then there's a draw while the ignition's off - like an alarm which could be the source of the problem.
Next then, with the engine running you get about 14.7v across the terminals this should rise a little when you rev the engine but not much. If it spikes to about 16v the reg rec isn't working.
If your getting lower than 14v then the alternator could be to blame. First of all check the wires from it into the loom. Then take the cover off and check the windings don't look burnt and also look at the pick up, make sure it's not bent on the mounts.

[sethbrown]

hiya,

thanks for the post mate.

i found that when running the volts drop as you draw off any power i.e lights etc, so is 100% a charging issue and not battery. i have checked all conections in line from generator to battery and rectifier and cant find any fault ive also checked the windings in the generator itself and can find any signs of them being burnt out.

i supposse ill have to disconnect the cables both ends and test them! !!!!!
was kind of hoping it would be a simple fix or common issue with these bikes!

does anyone know how many fuses a yamaha fzr400 should have? i have only found one on the main ignition power from the battery am i right in thinking it should be fusesed from the generator?

again any help would be much appreciated,

seth

[thunderace]

If you've got a 1WG, there should be a bank of fuses (about 5 in a junction box) fitted on top of the battery. Not sure if the 3TJ is the same?

[Evilchicken0]

There aren't any fuses from the generator.
There's a wiring diagram if you go into Manuals from the front page of the site. The quickest thing I'd say to do is change the generator for a seconhand unit but you'll need to know whether you have a 3TJ or 1WG model ... Do you have a single trapiziodal headlight (with 2 lamps) or twin round headlights ???

[sethbrown]

thanks all ill have a look later cheers for the heads up,

its a 3TJ 1992 N reg

thanks for all the replies

[Evilchicken0]

Ok then - the 3TJ genny is attached to the casing with allen head bolts - it can be a right stard to get out. The casing itself is 3TJ only because of the way the wiring is routed but I think the generator is common to the FZR600R Foxeye and Thundercat (but I don't know for certain). It might be easier to get these rather than a 3tj one

[Taggyd]

ive got one i believe is from a 600! not much wrong with it pm if interested!

[sethbrown]

anyone know where i can get a wiring diagram for a 3TJ??

[Taggyd]

See Evil's post above!