variprice 50 not consistent

[callmike2]

The coin mechanism on my 64FS is not consistent.  One time, 50 cents; next time 35 cents; next time $1.25.  No rhyme or reason to the amount that it takes to trip the bottle release relay.  Jumpers are set to 50 cents according to diagram in the mechanism.

Anyone dealt with this problem that could share information?

Some pix are included.

Thanks!

[Jim]

I'm not well versed on this mech, but I would start by making sure all the contact areas for the price jumpers are clean and set correctly...

[callmike2]

I double-checked the jumpers first thing.  I didn't clean the contacts.  Good idea. 
Thanks for the good info.