lower SG

arby

I performed an Equalization charge on my Surettes and it seems that with random hydrometer tests, the SG went lower.
Is this possible, and if so , why?
TIA

inetdog

Re: lower SG

arby wrote: »

I performed an Equalization charge on my Surettes and it seems that with random hydrometer tests, the SG went lower.
Is this possible, and if so , why?
TIA

This is not generally possible for the true SG, although the equalization charge might reduce stratification and cause a lower apparent SG if and only if you were dipping your hydrometer tube to the very bottom of the cell instead of from the top.

The other thing to consider is that you probably increased the battery temperature quite a bit and if you are not applying temperature compensation to the SG reading (either from a compensating hydrometer or from manual calculation) you will read a lower SG for the warmer electrolyte.

waynefromnscanada

Re: lower SG

Also check that you have not "sucked up" too much liquid and have the float hitting the screen/physical barricade at the top of the glass tube, which would not permit the float to find it's proper level. Another possibility is fine gas bubbles in the electrolyte, the result of recent EQ "overcharge", this would cause the float to sink lower until all the gas is released. Wait an hour or so after charging and try again, being careful to only draw up enough liquid to raise the float so it floats freely.

vtmaps

Re: lower SG

waynefromnscanada wrote: »

Another possibility is fine gas bubbles in the electrolyte, the result of recent EQ "overcharge", this would cause the float to sink lower until all the gas is released.

Huh? In my experience, the small bubbles stick to the float and cause the float to float higher, not sink lower. Are you suggesting that small bubbles in the electrolyte make it less dense (causing the float to sink lower)?

Arby, hydrometers need to be clean to work reliably. You must rinse them with distilled water after every use. If you don't rinse them, the surfaces get sticky and the float will stick to the sides of the tube and give you erroneous results. Before I figured this out, I used to get any reading I wanted... I just kept tapping the hydrometer until the float stuck in the position that made me happiest.

--vtMaps

arby

Re: lower SG

vtmaps wrote: »

Huh? In my experience, the small bubbles stick to the float and cause the float to float higher, not sink lower. Are you suggesting that small bubbles in the electrolyte make it less dense (causing the float to sink lower)?

Arby, hydrometers need to be clean to work reliably. You must rinse them with distilled water after every use. If you don't rinse them, the surfaces get sticky and the float will stick to the sides of the tube and give you erroneous results. Before I figured this out, I used to get any reading I wanted... I just kept tapping the hydrometer until the float stuck in the position that made me happiest.

--vtMaps

I like that system. )))
Same when I am going down south for a week. I check all of the weather forecasters until I get one that says sunny every day.