Crank seal placement in Weedeater motor?

[golem]

Trying to find info for a friend that is replacing the crank seal on a GB120 blower engine. Although I've not seen it he said the seal has about 1" of area fore and aft between the bearings in which it could be placed as there is no seating boss. His concern is that placement would effect chamber volume therefore intake mixture. I'm inclined to think it not that critical but said I'd ask around as nothing could be found researching the web.

Seal is item #42 in image.

 

[LegDeLimber]

IF you are just trying to get the new seal in the original location,
I would look for the wear line on the crankshaft, where the factory seal was.
Might be sort of faint, hard to see , But it will be there.

edit: make sure that the location of the seal is a proper fit.
That there isn't a draft angle/ taper that would allow the seal to not fit properly

As for importance of the seal position?
Without seeing the motor, I would be mostly concerned if there was a way for some sort of fuel/oil "puddling" to happen in that area.

I would imagine that could , *possibly*, cause a little stumble of the throttle response.
If you roll the motor to an angle that dumps the puddle
while hitting the throttle.

Not saying that I think it's likely to be a problem, just doing a little bit of armchair speculation to see if it it helps stir any useful thoughts.

Looking at the diagram. I'm assuming that items 40 & 43 are bearings.
But what is #39?

Sorry that I don't have a better response for you.