I just made a 40 gallon batch. It passed 3/27 test, but would not wash. I read on another thread that it won't wash cleanly probably because the batch was not completely reacted; I problably have mono- and diglycerides.
For 40 gallon batch, how much methanol should I use? I hate to use the full 8.8 gallons again.
Do I do a normal titration use the amount of KOH determined by the titration? Or do I use a certain amount per gallon???

Hello B. Rodgers, welcome to the forum

Can you be specific as to what you mean by would not wash.

If your biodiesel passed the 3/27 test it is unlikely your problem is mono or di glycerides.

I washed 7 times with warm BD (90F) and hot (110F) water. After the shake test, the water was not clear. I've had all other batches wash in 3 or 4 washings and the water in the shake test be clear after the last wash.

Hello B. Rodgers

The sooner after production you wash, the less soap that has settled out and the more soap you will need to wash out.

If possible wait several days/weeks before you wash and you will find that the biodiesel washes very easily

I suspect that if you allow this batch to dry and sit for a week your Shake-um up test will be very clear.

is your water soft??
the softer the water the less likely the shake test will pass. also the shake test is a poor test anyway.

if you really want to know the soap levels, measure them. check the CBT for how to measure soap.

just so do think I off my rocker...
I have measured the soap level when the BD was reasonable clear but the wash water wasn't..think skim milk colored...but the soap level was less than 100PPM..

-dkenny