I have a 90 which had belt slip when I got it. That was do to wear on the saw frame guide hex and arm, filing a relief chamfer front and rear of the guide to allow it to dodge the wear ridge fixed that. If yours comes with a very loose guide thats the reason why.
You should have two bits of bent rod sticking out of the dash pot, one attached to the arm and one free. Twisting the free one (half turn) will change the damping rate least to most. Engine oil works fine in mine. If the oils is too thick or too much damping selected your cut rate will be pathetic. Mine is happy with an 18tpi blade, but it has a bigger motor than yours. It will still bind and stall if the work piece moves in the vice, also watch outboard support.- too much and the cut closes on the last strokes, binds, stalls the blade and gives a smoking belt.
Make sure the crank rod is oiled properly.
Enjoy fairly quiet cutting 