Chainsaw oiling issue, I'm stumped...

[adw]

Completely different pump on the 288xp, fully adjustable pump, if you have changed the pick up pipe and filter it rules that out, as I tried ( maybe not well enough) the oil pump shaft rotates, however it has to have a throw to pump oil, so it rotates and moves in and out, this allows it to pick up the oil on the rearward  stroke and deliver on the forward stroke, the flat on the pump shaft is timed to the pick up and delivery holes in the pump body to achieve this, to increase oil flow you cannot increase the pump speed as this is controlled by the engine speed, so it is achieved by increasing the throw of the pump shaft, so either the shaft is not rotating, or you have no throw on the shaft, I.e the shaft is only rotating.

[spudulike]

My generic oil issue check.....flush the tank with a bit of Diesel/Petrol/Spirit, Check the pickup pipe and attached filter - pop a bit of WD40 down it and make sure it comes out of the filter - do not use an airline on it as it will BURST!!!

Inspect the pinion oil pup drive gear, it is easy to miss damage so inspect for a flat on the worm thread and also look at the start of the thread and follow it whilst rotating the gear, I have had one where the thread was broken and ran in to itself instead of completing the path to the end of the pump thus stopping the pump rotating.

FInally, blast some WD40/cleaner in one end of the pump and expect it to come out of the other freely if the housing is worn or less freely if it is in good order but.....you should beg some through. Blasting with a compressor is fine, wigling any blockage out with a pin is an option and, depending on the pump, you can often see a blockage or see the pump shaft if it is OK. Blockage is more likely to happen on the pickup/Input side.

This should fix most pump issues. Pump housings do wear to the point they stop working, the initiated can tell from blowing down a pit of fuel pipe pushed against the pump input or outlet holes.

[Patrick goulding]

Thanks guys I will have another go at it. Thanks. 👍 

[Matthew Jones]

9 hours ago, peatff said:

 

The bar oiling system is pumped not driven by crank case pressure. When you say the oil isn't really flowing how much oil is coming out of the bar feed hole ? It does only creep out of there not come out in a jet. Try some thinner oil.

 

Thanks Peatff,

That's rule that out. Yes i'm not expecting a jet but I would say it's coming out of the bar feed hole intermittently at best. I'll try some thinner oil though and see if that makes a difference.

 

Cheers

[Matthew Jones]

7 hours ago, adw said:

The 440 has a filter in the base of the oil tank, it is held in with a single screw, you can see it if you look underneath the saw between the fuel tank you will see it, also bear in mind for the oiler to pump it needs a throw on the shaft, on the non adjustable pump this is achieved by an eccentric cut into the the nylon gear, and a small pin pressed into the crankcase, if the pin has fallen out you loose the throw and no pump.

Hi adw, Yes the light grey filter that you can access through the bottom of the saw. I have removed this cleaned it and also replaced it with a brand new one so don't think that's the issue.

 

That's interesting what you say about the for the oiler to pump it needs a throw on the shaft. I'm not sure I follow this..😬 and what do you mean by an eccentric cut into the nylon gear?

 

I don't suppose you would know the part numbers to these so I can look them up and know what i'm looking for?

 

Thanks so much

[Matthew Jones]

1 hour ago, spudulike said:

My generic oil issue check.....flush the tank with a bit of Diesel/Petrol/Spirit, Check the pickup pipe and attached filter - pop a bit of WD40 down it and make sure it comes out of the filter - do not use an airline on it as it will BURST!!!

Inspect the pinion oil pup drive gear, it is easy to miss damage so inspect for a flat on the worm thread and also look at the start of the thread and follow it whilst rotating the gear, I have had one where the thread was broken and ran in to itself instead of completing the path to the end of the pump thus stopping the pump rotating.

FInally, blast some WD40/cleaner in one end of the pump and expect it to come out of the other freely if the housing is worn or less freely if it is in good order but.....you should beg some through. Blasting with a compressor is fine, wigling any blockage out with a pin is an option and, depending on the pump, you can often see a blockage or see the pump shaft if it is OK. Blockage is more likely to happen on the pickup/Input side.

This should fix most pump issues. Pump housings do wear to the point they stop working, the initiated can tell from blowing down a pit of fuel pipe pushed against the pump input or outlet holes.

Thanks Spud, I have done all of this and inspected and changed the worm gear and pump piston for brand new parts. So I think I have these covered. Thank you though

[Matthew Jones]

I flushed out the oil tank again yesterday with some spirit and I noticed there was a leak of this spirit which seemed to be coming from the crank case somewhere and building up at the base of the flywheel. Can the crankcase have leaks in the tank itself?

[Matthew Jones]

1 hour ago, Patrick goulding said:

Thanks guys I will have another go at it. Thanks. 👍 

Good luck Patrick!

[skyhuck]

I had a similar issue with a different saw, Dick Leigh fitted a spring inside the oil pipe. A sort of "stent", it appears the pipe was kinking and stopping the flow of oil.

[Matthew Jones]

Thanks skyhuck, I just replaced the oil pipe as it wasn't too costly