New VR, Now System Not Charging????

Hello,
1998 Merc Force (OE 339847) 40HP 2-stroke. My tach stopped working and I traced problem to VR (with help from fucawi!). At that time my charging system was working fine putting out 14.5 vdc at battery. Anyway, I installed a new CDI 194-5279 VR. I smeared some heat sink compund on the back of the VR as the instuctions suggest.
Now my tach works, but my charging system is putting out around 13vdc.
Now I must say that I did not have the boat in the water, and only ran the motor dry (I know) at idle a couple of seconds to make sure the tach worked. Which it did. Not wanting to damage the impeller, I turned off the motor after a few seconds of run time.

I was wondering if I have to rev up the RPMs higher to make sure the output of the VR goes up. Is this normal?

Thanks,
-Nels

Re: New VR, Now System Not Charging????

My understanding is that yes you have to rev up the motor to get it to charge higher, i may be wrong on this but that was my understanding. Hope it is correct and help ful.

Re: New VR, Now System Not Charging????

ya you have to increase rpm for the voltage to increase.. you better replace the impeller before you go boating again... only takes a few seconds to a reduce flow of water and/ or destroy it ..

Re: New VR, Now System Not Charging????

as long as you are sure the heat sink compound is not isolating the back of the regulator which is probably the earth ....always run water ..use muffs

Re: New VR, Now System Not Charging????

You need about 2000 rpm to get up to 14.5. 13 at idle sound ok to me.

Re: New VR, Now System Not Charging????

Thank you all for your feedback.. I know running it dry, however briefly, is a major no-no. The impeller has two hours on it so I hope it will be OK. Will give it a good test this weekend...

And I will check to make sure the case has a good engine ground.

Thanks Again!