Camshaft bearings

[NMills]

Hey guys.. quick question.... on the camshaft bearings... should the exposed bearing be facing inwards or outwards??? i see that one side is protected and the other not... just curious if it matters... right now the balls are lookin inward...

thanks..

[PaRedneckRiders]

Originally posted by NMills
Hey guys.. quick question.... on the camshaft bearings... should the exposed bearing be facing inwards or outwards??? i see that one side is protected and the other not... just curious if it matters... right now the balls are lookin inward...

thanks..
IIRC that is right, the sealed side goes out ill go check the manual and post back later unless someone beats me 2 it.

[NMills]

my manual says nothing about which way... it just says make sure they don't drop down the hole...

[PaRedneckRiders]

Originally posted by NMills
my manual says nothing about which way... it just says make sure they don't drop down the hole...
O i thought it said something.
But ya im pretty sure its sealed side out.

[NMills]

As long as i can find out by tuesday.... i'm sure it'll be fine...

[WoodTRD]

The sealed bearing goes next to the cam sprocket with the seal side facing out

[NMills]

so both seals out... gotcha...

[hocman123]

thats odd all the 400 i have worked on all had one half seal bearing and one open bearing but ethor way seals out

[NMills]

Not mine... both have one side closed and one side open...

[10sball]

all three of the ones i have been in have had only one seal near the cam gear.. the other was open

[WoodTRD]

Yea on mine just the one next to the sprocket had a sealed side and it was facing out, the one on the other end had no seals. Maybe they've been replaced before?

[NMills]

i don't believe so... could be wrong...

[NacsMXer]

Originally posted by WoodTRD
Yea on mine just the one next to the sprocket had a sealed side and it was facing out, the one on the other end had no seals. Maybe they've been replaced before?

No, that is the way the engine is designed. The seal is only on one side.

It is imperative that the bearing with the seal faces out/away from the camshaft on the cam sprocket side.

Note the two dowel pins that are on either side of the camshaft bearings which prevent the cam from moving side to side in the head. Underneath the cam sprocket side dowel pin is an oil passage that goes towards the bottom end of the motor. Oil is pumped from the bottom through that dowel pin and then into the small pocket in the head where the cam bearing rides. Because that seal in the bearing is facing out, oil in that pocket is able to "dam up" so it can be pumped through the hole in the end of the cam (notice the cam is hollow). It then comes out through small holes in the cam lobes/journals as it spins to allow proper lubrication.

There is no oil passage in the pocket on the other side where the non-sealed bearing rides.

If that seal were not there on the cam sprocket side, oil would pass right through the bearing. The oil would not be allowed to "dam up" in the oil pocket so it could be pumped through the cam. You would starve the cam of oil, ruining the cam and rockers eventually.

That's why the magic seal is important on only that side :)

[eprovenzano]

Thanks for the info. I'm in the process of finishing a bottom end rebuild and wasn't sure which bearing went where.

Now I know and will install them properly. Sealed bearing facing out on the cam sprocket side

[NMills]

ok you guys were right... i do have one that is half shielded and one that is not at all... i guess i was just confused... shame on me..