Ive got a smallish generator which keeps on getting a flat battery,
the generator will run for a couple of days then when you go to start it again it has a flat battery, there was a bad connection on the alternator but that was fixed, if i leave it sitting with a charged battery for any time and go back to it the battery will be flat, what could be causeing the battery to go flat, could there be a short somewhere that is dischrging the battery???
the generator in question is.

Pramac P6000 Standard Silent Electric Start Yanmar L100 Dies :: TOOLSTOP

 

2 options really: either there is something discharging the battery as you say, or the battery is f**ked.

Presumably the battery is needed because its an electric starter..?

If the battery's a closed type (like one would have on a lawnmover or house alarm), then it will have a limited life anyway, so maybe a replacement is due.
If it's a car battery type then it may be one that needs "topping up".

The thought of a generator with a flat battery is still making me smile - oh the irony !!

Rich

 

Hah spose it is funny,
Bought a new battery for it (sealed type) when the prob started, been checked as fully charged then if you leave it for a couple of days its flat, so im guessing there has to be a short somewhere to flatten the battery, yeah to the electric start.

 

have you checked the open circuit voltage of the battery whilst genny is running? To make sure its charging correctly?

 

Chances are that there is a diode failed and the battery will be supplying the alternator (which will act as a heater) when the generator is off.

Andy.

 

As above, check the diodes in the pack on the alternator. You should get continuity if you put the probes on each end, then swap the leads over and then you should have an open circuit if one is broken....Or continuity both ways and its short circuit thus not rectifying the ac generated and instead of providing DC voltage to your battery to charge it, it's still ac.

 

Also check the belt make sure it's tight,you should only have about 10-12mm play in it if you push it up/down (or 1/4 turn twisting it)