Mini Mac Bar Oiler

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Scottnc

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Anyone intimate with the inner workings of the MM pulse bar oiler? Specifically, is it worth fixing (o-rings) and is it possible for one to leak so bad it becomes a crankcase vacuum leak? From comments found while using search it seems the MM is notorious for not running, starting. My dad bought this saw new in '73 I think, mom said the dealer had it more than he did. As bad as the oiler has always leaked and discovering it is crankcase pulse powered got me to wondering if plugging the crankcase hole might not be in order.
 
This is a very strange oil pump but it doesn't normally cause and problems with how the saw runs. With the saw sitting for awhile it can allow bar oil to drain into the crankcase which can cause hard starting and a lot of smoke when it does start. If you plug the pulse source from the crankcase, it won't work at all.
 
After a lengthy internet troll I have located most of what I wish to replace while this saw is apart, just wish I had found one-stop shopping as the freight will be more $ than the cost of the bits ordered. I'm gonna take a stab at resealing the oiler, new rings, seals, ignition parts and see how the saw runs. Going back through the carb again too, had less than thirty minutes run time when it started acting up. Again. Might be the "kit" used was old stock and dried out. It was fine off the bench but after putting it to work... It acted like a it had a holed carb pulse diapragm or crankcase leak - had to constantly play w/carb settings, sensitive to saw positioning (overhead tree pruning) and very hard to restart after it either died on its own (when returned to idle) or was shut off. The last straw was when it wouldn't even run cleanly at WOT. Last year I felt the oiler wasn't correctly installed hence the leak. At teardown this time it was obvious the bar oiler was leaking. Bad as ever, I swear it puked a quarter tank of oil.

Mark, the old thread was very helpful. Thanks.

O2S, the oiler being a crankcase leak was a wild a** guess, I was wondering if an attempt at repairing it was akin to beating a dead horse.
 
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