mag side crank seal -- which way?

[Gippslander]

Hi, am rebuilding my 73 CR250, and I have forgotten which way the magneto side crank seal goes in -- cant see it mentioned in the Haynes or the Factory manual 

I recall that the lip/spring faces in toward the crank with the flat/smooth side outwards -- is that correct?

Was on the 'phone yesterday to a Husky fanatic from Melbourne and he mentioned a bike he came across years ago that was a pig to start -- was a seal in the wrong way -- and I confidently had a laugh and agreed with him about people who don't know the basic stuff like which way a seal goes in -- now (one day later) I am unsure -- must be the beer

Thanks

[Barclay]

lip facing out ,idea being sealing dirt out and the negative pressure of the crank case pulling the seal on to the crank.
Possibility of the spring jumping off the seal when tapping it in and going into a main brg is also a very good reason .
cheers Boots

[Gippslander]

Thanks Boots -- now to go to the shed and put it together

[PEZBerq]

Not sure about 73 models..... but I know 78 and later Husky LH (ignition) side crank seals on models with the alloy seal holder plate go in with the flat end facing out (spring is exposed to the bearing). Parts book clearly shows this and all the ones I've pulled down have always been found this way.

[Gippslander]

Mmm -- I have not got to the seal bit as yet -- but the clutch/left side has the lip pointing out to stop the oil getting into the bottom end so that way round must work -- and the "danger" would be sucking air -- blowing fuel laiden air out is less likely -- so perhaps the "rule" is to have the seals to stop air/oil getting in

BUT -- have just put the case halves together -- and only seem to have 3 gears -- like my first bike a 125 Bantam 

So there will be a lot of lookin' and thinkin' tonight -- do not want to assemble any further unless I can clearly get 5 gears -- the selector forks could be in the wrong way -- there are 2 the same and one with a longer "tab" and it's a bit hrd to get them mixed up -- BUT I'm the one who could do it 

Any tips???

[bigk]

You have to "time" the transmission by setting it up in third gear, (4th for 6 speed models), not neutral. This will be your problem if you haven't done it this way.
Cheers,
K

[Mike52]

Not sure about 73 models..... but I know 78 and later Husky LH (ignition) side crank seals on models with the alloy seal holder plate go in with the flat end facing out (spring is exposed to the bearing). Parts book clearly shows this and all the ones I've pulled down have always been found this way.

Yer that,s what I thought too.

[Gippslander]

Hi BigK -- yep -- timed it in third -- remember you tellin' me that a while ago -- some things stick -- will be something silly -- anyway have a puller to get the right hand side case half off -- the CZ one I got from Jiri Starec at Xmas works spot on   (just had to buy something from him -- and did not have the foldies for a twin port)

So I'll look and if I cannot work it out will split em and look and see -- the gear clusters should all be in the correct order and all of the spacers and bushes all in the correct spots because I did not pull them apart -- just lifted them out and washed in petrol and blew dry and inspected -- so they will be ok -- it's gonna be the shift forks in the wrong way/place or not timed in third like you said.

Also -- the change pawl and linkage that works on the shift drum might be the problem -- I think I got the gear that works on the teeth on the bottom of the drum in the correct posi' -- like the book says -- so you can see one tooth out one side and two teeth out the other side -- if that's wrong I could be missing gears but I would be missing 1/2 or 4/5 because if it's in the wrong posi' it will be too far to the left or too far to the right.  If I am missing 1/5 then it will be the timing or the shift forks.

Crikey -- all that sounds like I know what I'm talkin about -- and that's not the case

[PEZBerq]

BTW don't confuse the dust seal lip with the actual oil seal lip. The oil seal is not energised by differential pressure to my understanding and even if it was the difference in a motorcycle engine is too small to be of any note. But then again I could be wrong....has happened before 

[Gippslander]

Thanks PEZ -- the seal I have is a "nitrile" from the bearing service -- seems to be what is used now a days -- and only has the one lip with a tension spring on it -- so no dust lip or anything fancy like that.

Jeepers -- is there an old Husky spannerman out there who has rebuilt lots of these and can just say -- "listen here Gippslander ya dill -- it goes this way!" 

[Gippslander]

Local bike mechanic Fozzy -- tells me the lip faces in -- so that's the way it is installed -- and the bike runs ok.

[PEZBerq]

Excellent news    Here is what all my Husky's are like.