Chainsaws

Gary,

I have a few Model 455 chainsaws, one being the exact same date of manufacture too. Anyhow a couple of scenario's to consider, I just experienced one of them myself, so here are some possibilities:

1. Putting the chainsaw away while its still warm or hot, the excess barchain oil will run  back in the bar rails and it will pool, in one spot just about where the clutch is located.

2. Storing the chainsaw in Warm environment (ie a storage shed, or warm garage that may reach 90 degrees plus), the oil will expand, and if the environment is warm enough it will create pressure in the tank and push the oil out of the tank and through the pump and  out the discharge line.

3. The oil suction line to the pump is attached to the bottom of the oil tank, this cannot be readily seen unless you remove the front bar handle (grey colored) which also goes under the crankcase. It is a molded rubber oil suction line, which has a grommet in the line, It is possible that the grommet is not properly installed or damaged, and oil is leaking from this location.

4. The model 455 changed there design of the oil pump, I think around 2012. Anyhow the older oil pumps were just a round barreled pump with a hole for suction, and another hole for discharge, there is no fittings for the lines, it just depended on the compression of the rubber parts of the suction and discharge line to prevent leakage. The newer pumps, they have created a raised boss area on the barrel which the rubber lines are compressed over, I believe this was an attempt to reduce leakage.

Items 1 & 2 are easy to check out, and see if they are a problem, by the way Item 2, was my most recent problem which my garage got close to 100 degrees, and caused the oil to pressurize the tank, and leak out, also had a 1 gallon plastic gas can which got pressurized and broke the plastic cap off the can too!

Items 3 & 4, will require a little disassembly but not too bad, Item 4, you will need to remove the clutch cover, bar and chain, the clutch and drive sprocket, the metal guard plate and oil pump gear. Then there will be one screw that holds the oil pump in place, you will then be able to see the oil pump lines and fittings, and what kind of pump, or if it is leaking.

I hope this helps,

PS. I would also inspect the oil pump suction line and discharge rubber lines for any damage or possible leakage, then clean everything thoroughly and re-assemble.