560xp infinite worm drive replacement...

[Smorgasbord]

Hello all,

This is my first ever post here after lurking for years but never needed to say much!

 

So my 10 year old 560xp, which has had a lot of use and is still running well, has started giving me a massive headache with the worm drive.

Last July the oil stopped flowing for the first time ever in it's life, turns out the worm drive was worn out - thread mangled.

The replacement worm drive lasted to mid last winter, then same thing - oil stops flowing and drive's thread is mangled.

This then happens again several times in a row for the last few months; I'm now on my 8th worm drive since last July!

I replaced the oil pump last week, but the previous pump was running fine and after a full strip-down and clean I'm confident it wasn't the source of the problem.

Cut firewood for a few hours last week after replacing oil pump, then a few hours today before the oil stopped again.

 

The parts are definitely correct for the saw and they are fitting correctly.

There is no play in the oil pump and the oil flow is good, all the lines clean etc.

When I put a new worm drive in it oils fine for a few hours then eventually the thread becomes mangled.

 

I've now replaced the pump, worm drive, needle bearing, sprocket, clutch drum, clutch AND even the clutch cover - all new parts.

Is there any other possible known cause for such a consistent and frequent issue like this?

Has anybody else had this issue?

 

See pic of last 6 worm drives all with almost identical wear on threads.

 

[Stubby]

20 hours ago, Smorgasbord said:

Hello all,

This is my first ever post here after lurking for years but never needed to say much!

 

So my 10 year old 560xp, which has had a lot of use and is still running well, has started giving me a massive headache with the worm drive.

Last July the oil stopped flowing for the first time ever in it's life, turns out the worm drive was worn out - thread mangled.

The replacement worm drive lasted to mid last winter, then same thing - oil stops flowing and drive's thread is mangled.

This then happens again several times in a row for the last few months; I'm now on my 8th worm drive since last July!

I replaced the oil pump last week, but the previous pump was running fine and after a full strip-down and clean I'm confident it wasn't the source of the problem.

Cut firewood for a few hours last week after replacing oil pump, then a few hours today before the oil stopped again.

 

The parts are definitely correct for the saw and they are fitting correctly.

There is no play in the oil pump and the oil flow is good, all the lines clean etc.

When I put a new worm drive in it oils fine for a few hours then eventually the thread becomes mangled.

 

I've now replaced the pump, worm drive, needle bearing, sprocket, clutch drum, clutch AND even the clutch cover - all new parts.

Is there any other possible known cause for such a consistent and frequent issue like this?

Has anybody else had this issue?

 

See pic of last 6 worm drives all with almost identical wear on threads.

 

@adw

[GarethM]

Blocked strainer or too thick a chain oil ?.

 

Just thinking either of those would strain the pump and cause excessive pressure and wear.

[Muddy42]

54 minutes ago, GarethM said:

Blocked strainer or too thick a chain oil ?.

 

Just thinking either of those would strain the pump and cause excessive pressure and wear.

Or a blocked oil tank vent?

[htb]

Had the same on 200t, when using veg oil, if used infrequently it starts to gum up/thicken and screws the worm gear. Changed back to oregon chain oil or Rye oil, never had a problem since.

[spudulike]

That sort of damage is usually caused by the oil pump gear being tight and the pinion worm drive then strips as it can't turn the gear correctly so.......why is the oil pump gear not turning correctly? Dirt, cheap/thick oil, oil pump not installed correctly.....

[adw]

Just one additional point, the early 550/560 had the black oil pump, the gear was driven by some spikes in the back of the sprocket, the later white pump had a gear driven by the splines of the sprocket, so have we got/ had a mix and match of sprockets, pumps and gears? 

[Mark_Skyland]

As ADW says it could be a mismatch. Post a pic of the worm wheel showing a top down view and the drum showing the part that locates into the worm wheel.

 

You can see the differences in the drum here

Clutch Drum Assy - Husqvarna 575261005

SKYLANDEQUIPMENT.COM

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Clutch Drum Assy for Husqvarna chainsaws. * PLEASE NOTE: 560XP Only fits upto serial number 20202200048 * From serial number 20202200049 please use part number 575 26 10-09...

 

Clutch Drum Assy - Husqvarna 575261009

SKYLANDEQUIPMENT.COM

---

Clutch Drum Assy for Husqvarna 560XP chainsaws. * PLEASE NOTE: 560XP Only fits from serial number 20202200049 onwards * From serial number upto 2020220004 please use...

 

[Stubby]

8 hours ago, adw said:

Just one additional point, the early 550/560 had the black oil pump, the gear was driven by some spikes in the back of the sprocket, the later white pump had a gear driven by the splines of the sprocket, so have we got/ had a mix and match of sprockets, pumps and gears? 

Smells like this to me . 👍

[Muddy42]

The weird thing is the OP said they have replaced the pump last week, so it wont have had time to fail or block up?

 

Are all replacement parts OEM and with part numbers that match those listed as compatible in the manual? As above has there been a mix up.

 

Before you fitted the pump was it easy to turn manually?