Stihl HT 75 chain not oiling.

[Peter.N.]

There appears to be a non return valve between the reservoir and chain case, have cleared it but still no oil. It doesn't appear to have a pump, at least if it does I can't see it.

Can anyone help?

Thanks. Peter.

 

[lostinthelight]

There appears to be a non return valve between the reservoir and chain case, have cleared it but still no oil. It doesn't appear to have a pump, at least if it does I can't see it.

Can anyone help?

Thanks. Peter.

 

[Burnerman]

If there is a tiny gear driven pump there, they always block......try running some light oil / paraffin mix through the machine and they usually clear after a while.
John

 

[Peter.N.]

Thanks for the video, normally the first place I look - getting old!

Hi John, thought I might see you, hope you are well and thanks for the info.

Peter

 

[Burnerman]

Hi Peter
https://www.lsengineers.co.uk/oil-p...MI54emm9_P9gIViNPtCh3vZgROEAQYASABEgIM2_D_BwE
This is the usual oil pump, driven by a worm gear that spins it. I've no idea if this is what your machine has though as I've never had to replace one on a pole pruner but I'd assume there must be something somewhere - or how would the chain get oiled?
It's an interference fit in the aluminium casting.
Regards
John

 

[Peter.N.]

That video was the right one John, only judging by the repairers hands it probably had more sawdust in it when he finished than when he started.

Yes that's the pump on your link. The removal instructions on the video were very useful

Peter

 

[foxhole]

Sawdust was always blocking oil when I had a chain saw.

 

[Peter.N.]

Never had a problem with my ordinary Stihl but this one has a different system. I've got the pump out now and it is indeed clogged with sawdust.

Peter

 

[Peter.N.]

Fixed the oiler but still have a problem. The chain was supposed to be new and it looks it but it only cuts halfway through a branch then smokes trying to cut through the second half and does very little cutting, in fact I have had it stuck in the tree two or three times. I have cut down from the top but about halfway through the branch splits and jams the the chain.

I have an ordinary 12" Stihl saw which I have used for many years, don't have any trouble with that. I have tried sharpening the blade but it doesn't seem to make any difference, I'm using a 5/32" file, 4mm? that sharpens the other saw fine - what am I doing wrong.

Peter

 

[lostinthelight]

If the bar jams as the branch splits try cutting away from the trunk as in the lower sketch.

 

[Burnerman]

Can I suggest you buy a quality Oregon or War-Tec chain from GHS or similar Peter? Your file should put a keen edge on the chain so something isn’t right.
John

 

[Peter.N.]

Could be that John but I have had all sorts of chains before and not had a problem. The chain looks and feels sharp although it looks different to the chain on my other 12" saw. I wondered if it needs a smaller file, the one I use for the other saw is a bit of a tight fit but I found a couple of thinner ones today so will try that.

The strange thing is it cuts through the first half of a branch OK but seems to object to cutting it all the way through.

Peter

 

[Burnerman]

That's curious Peter - unless you have a Powersharp or low profile chain I reckon they are very similar.
Personally I don't find using a slightly larger file makes any difference to the cutting edge - but of course you can't go back to the smaller one!
Is the chain matched to your bar?
Regards
John

 

[Peter.N.]

Well it fits John, otherwise I don't know. I think it said something about a 'pico' chain.

Peter

 

[Burnerman]

Picco chain, as far as I know, is favoured by chainsaw carving people....I can't say I've ever had the pleasure!
No experience with this one, I'm afraid.
John