OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Chainsaws and Concrete Cutters Petrol Chainsaws and Concrete Cutters McCulloch chainsaw with oil leak

I've got a small McCulloch chainsaw (14") which runs GREAT except that when the saw sits overnight, the oil siphons out of the oil tank via the orifice at the bar (ie. where it's supposed to come out when the saw is running), and in the morning the saw is sitting in a puddle of oil.

What might the problem be?

I have a McCullock Timber Bear 24" with the same problem. It gets quite messy. It's been leaking ever since I bought it new from Costco. I wish I'd taken it back. Don't see any replies to help you. I guess I'll post the question too.

Jim Hartley - Heartspire@earthlink.net

You say you have a 14" McCulloch that leaks oil, tell us the exact model of the saw because there are a lot of them.
One thing to consider is that every chain saw made has an air inlet hole in the oiler system to let air back into the oil tank as the oil is pumped out. On some saws this inlet may be slightly below the highest level of the tank and if a saw is stored with the oil tank completely filled then normal temperature changes cause expansion of the oil and push it out the vent hole. Usually it will not cause the whole tank to empty though. One some other saws that use a pressurized oil tank system you have to bleed the pressure from the tank when you have been cutting before you store the saw, otherwise the pressure in the tank will force all the oil out.

Well the 14" inch saw is probably leaking cause of the oiler hose connections which was remedied by a new oiler system. The 24" inch from costco is leaking probably between the oil tank and the cylinder stuffer plate. You'll have to the saw apart and clean the tank and stuffer plate and put a small bead of "YAMABOND #4" sealer around the tank and assemble saw and that should fix your problem.Unless of course you broke the tank by missing the bar adjusting nut and bent the screw and poked it into the tank !!!

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Rick

Thanks for that, Rick.
Checking out the hose junctions was one of the first things I did, and I applied sealant (teflon tape) to them just in case they were the culprit. But the leakage continued.
So then I took the bar off, and could actually see the oil coming out of the delivery hole (whatever it's technically called)-- just siphoning out all by itself. So I suspect that the internals of the oil pump may be stuffed.
If it is the oil pump (and I think it is), what would you say are my options now?
Cheers,
Mike.