Stihl 170 crankshaft seals replacements

[Ratman]

Ahh that's really annoying! I've not looked at the 170 as I don't own one. If you have to strip it down fully then yea, just buy a new one. 

The puller you suggest will do for the pro saws, the 170 clamshell and the likes are homeowner saws. If its only your own time and the history of the saw is good and everything engine / crank wise is good then sometimes theyre worth doing. Caber rings £10 to ya door, bearings and seals about £15 to ya door (ok wont be oem but good enough for a home owner saw)

[Ratman]

Not got the bottom pan but you can see the two ridges that the seal sits between and then lines up nice and square once theyre in situ.

[Paddy1000111]

5 minutes ago, Ratman said:

Not got the bottom pan but you can see the two ridges that the seal sits between and then lines up nice and square once theyre in situ.

I see what you mean. I wonder why it says you can do it in the workshop manual? 

[Ratman]

Pass! 🤷‍♂️ but you defo cant do em cos the clutch / oil pump side seal is partially hidden behind the crackcase housing once the engine is all in place. Think you’ll visualise what i mean from pics below

[ChrisNewport]

You can remove and install the seals without splitting the engine, there are 2 types of seals, one set you use when splitting the engine and the other type you use when not splitting the engine.

[bmp01]

46 minutes ago, ChrisNewport said:

You can remove and install the seals without splitting the engine, there are 2 types of seals, one set you use when splitting the engine and the other type you use when not splitting the engine.

Ha, that's useful info. I wondered if that was the difference between the 2 types of seal listed.

And why do they have the lip in the housing anyway ? Its not a feature that exists in many other split bearing designs. Think I'd be tempted to dremel the lip away 😈 😨

What about access behind the clutch though ? If you have to take the engine out that's still 90% of the effort / time / money...

[ChrisNewport]

16 minutes ago, bmp01 said:

 

What about access behind the clutch though ? If you have to take the engine out that's still 90% of the effort / time / money...

I wouldnt know about that, only reason i know about the different seals is because my local dealer asked me which ones i wanted when i was building my 170. As it was already completely stripped down i opted for those so i couldnt say what the difference is between the two types

Edited May 16, 2021 by ChrisNewport

[Ratman]

I’ll just keep taking them apart, stupid not to take the pan off and check crank / bearings / piston / cylinder etc for the sake of 4 bolts and a splurge of hylomar, its less than 30mins to have one fully stripped and in bits, it takes longer to clean everything.

 

[bmp01]

I agree with you, once engine is out of saw just pull the pan off.

I've got a 170 2-Mix in bits in the garage, I'm going to mock it up to a look at removing the seal behind the clutch. Picture in due course...

[bmp01]

Well,  in amoungst grass cutting and shower dodging here's a piccy or 2. It is a 170 2 mix cylinder, think the brg and seal arrangement is the same...

Conclusion, seal will pass though the housing but will not pass the oil pump (another thing to remove then ).