Help! JLO Crank Shaft Seal PTO Side

[rturner]

I'm rebuilding my jlo 440 & my brain can't remember removing the old seal. when installing the new one does the flat side go in facing the crank or does the cup side with spring ? also some say use thread seal & some say high temp gasket seal to bond engine togeather any coments?? Thanks!!

[Bazooo guy]

All it says in the manual is "place the oil seal on pto end of shaft flush with the casting" Pg30/31
I would assume the spring and lip is on the inside.
Is the original seal the same as the new one?
Here's the manual look at pg36 spring looks to be inside on the twin cylinder.

http://www.vintagesnow.com/Engine_manuals_files/JLO%20Service%20Manual.pdf

[rturner]

I think now the cup with the spring is to the outside & the starter ring fits in that cup & I do see a small lip or bevel on the flat side that may fit just inside the crankshaft bearing. yes it is the same as the old. someone will know for sure.Thanks!

[Bazooo guy]

On the PTO side the spring should be inside.
The seal spring is on the inside if you want to seal the oil in.
If you want to seal the elements from getting in the seal would be outside.
We seal industrial gearboxes with 2 double lip seals 1 in and 1 out

[jessieherrera]

Hello,
The cup and spring definately go on the "Pressure" side which means on the inside. That goes with any seal whether it be on a motor, tranny, or wheel. The cup uses the pressure to force the seal closed. If you put the flat side in it will not create a forced seal.
Good luck.

[rturner]

Thanks for all the help. I would have lost that bet. what about sealing the crankcase, what should I use? Randy

[Bazooo guy]

I would use Permatex red (high temp) sealant?

[teeko]

I have always used "Three Bond" case sealer, available at any bike shop. It's intended use is specifically to seal crankcase halves where there is no gasket. One tube will cost around 20 bucks and last a whole lot longer than your machine.