chainsaw clutch drum needle roller lubrication?

[Old WoodChip]

I always used Red Fluid Grease, regular. Never had a bearing fail and too old to change habits now.

[broonie]

I always used Red Fluid Grease, regular. Never had a bearing fail and too old to change habits now.

I concur wi tha auld wise one lol

[gensetsteve]

Little and often. A tiny smudge every couple of months.

[David Heaf]

The first issue is to find out why the clutch is slipping, after this time, it is likely the clutch shoes are worn down and need replacing - it is also worth checking the sprocket as this can also have a channel worn around its inside where the clutch contacts it.

 

Thanks for this input.

 

The clutch drum was indeed worn, so I fitted a new one that I obtained from the USA, only this time with a rim sprocket. I cleaned the shoes and gave them a light rub with emery paper. I also managed to source a metal cage needle roller bearing (K15X18X14 from Kugellager Handloser, Germany, who have an ebay.de shop) for the clutch drum. However, the bearing is still seizing after a few hours of use, despite taking great care in avoiding stalling the chain.

 

The clutch shoes for a Sachs Dolmar 123 seem harder to source. Does anyone here know what the clearance between clutch and drum should be on a chainsaw when new?

 

Another factor may be chain tension. I could have been over-tightening it. The over tightening could be causing clutch slip before full revs are reached.

 

One feature of the design of the clutch freewheel that seems less than ideal to me is that any lubricant introduced into the needle roller bearing must be flung out at each end during running. On the inner end it must end up on the clutch drum, thus increasing the risk of slippage of the clutch. In any case, needle roller bearings that have seized are always completely devoid of lubricant.

[arboriculturist]

The clutch roller bearing only comes in to play when saw is idoling so it dos't need much lube. Only ever had 1 clog up when milling with fine dust.

 

"The clutch roller bearing only comes in to play when saw is idling"

 

Exactly! - says it all really.

[peatff]

As a general rule most do not lubricate the bearing for the simple reason that it attracts tiny wood fibers which will clog the bearing .There are some who will argue to lube it also .

 

I have heard that said of nose sprockets (and still don't understand why) but never for clutch bearings. It is part of the service regime and not doing it doesn't make any sense. You don't omit grease anywhere else because it "attracts" dirt or in this case wood fibres. It's there to fulfil a purpose and an unlubricated bearing is a disaster waiting to happen. Only reason not to lubricate is because it's a pain getting the clutch off.

 

The clutch roller bearing only comes in to play when saw is idoling so it dos't need much lube. Only ever had 1 clog up when milling with fine dust.

 

If your saw is making fine dust it needs sharpening All the chips under my chain cover are well soaked in chain oil and stick till I clean them out with brake cleaner, how does the fine dust get in there ?

[NFG]

It was always one shot of grease per week on old Husqvarna saws

 

Hi

 

Agreed, I lightly grease the roller bearing every 50 hrs use

 

Too much grease can cause problems so avoid 'over packing'

 

 

N

[arboriculturist]

I always used Red Fluid Grease, regular. Never had a bearing fail and too old to change habits now.

 

Hundreds of hours continual use on 346xp and 357xp - no grease - no failure - obviously both spent very little time on tickover!

[David Heaf]

Hundreds of hours continual use on 346xp and 357xp - no grease - no failure - obviously both spent very little time on tickover!

 

The odd thing is that for 30 years I was unaware that the needle roller bearing of my Sachs Dolmar 123 needed greasing at all. I never had it fail until a couple of years ago. Since then I've got through several plastic cage replacements that Makita now stock and one authentic part with a metal cage that a chainsaw specialist in Germany just happened to have in stock.

 

There is clearly something fundamental wrong. Today, using a lower chain tension than I've been using for the past few years, I cut for a few hours a sycamore that was wider than my 23" bar. The bearing did not seize but has clearly shed most of the grease I gave it. Also towards the end of the session the chain was inclined to run on tickover, a somewhat hazardous condition.

 

Too much grease can cause problems so avoid 'over packing'

 

Thanks. I'll implement this. Until I've diagnosed the problem, I'm inclined to clean and regrease the bearing after each work session.

[spudulike]

The odd thing is that for 30 years I was unaware that the needle roller bearing of my Sachs Dolmar 123 needed greasing at all. I never had it fail until a couple of years ago. Since then I've got through several plastic cage replacements that Makita now stock and one authentic part with a metal cage that a chainsaw specialist in Germany just happened to have in stock.

 

There is clearly something fundamental wrong. Today, using a lower chain tension than I've been using for the past few years, I cut for a few hours a sycamore that was wider than my 23" bar. The bearing did not seize but has clearly shed most of the grease I gave it. Also towards the end of the session the chain was inclined to run on tickover, a somewhat hazardous condition.

 

 

 

Thanks. I'll implement this. Until I've diagnosed the problem, I'm inclined to clean and regrease the bearing after each work session.

 

The chain running on at idle is most likely worn clutch springs. It is usual for the needle bearing to shed its grease over a short period of time - it doesn't harm in most cases!

 

If anyone wants a clean Dolmar 123, I have a nice one ready to go and looks low hours! It wont break the bank:thumbup: