Innie or Outie?

[953 nut 55,321]

I am assembling a couple of K-241 engines and have a question about the crank shaft bearings. One side of each bearing is open and the other side of each bearing is shielded.         On one of the engines the shielded side of each was turned out away from the crank case (open side in) and on the other both shielded sides were turned into the crankcase (open side out).    The bearings on both engines were good and had some oil on them when the engine was taken apart. All are in good condition. My question is what way would you feel is correct?               

[pfrederi 17,741]

Never have seen  a crank bearing with a shield...Logic would say open to the crankcase... but...???

[WHX?? 48,828]

Very interesting question Richard. I recently cracked open a motor,  almost think it was a small block CRS. Both ends had one side shielded bearings. Again CRS on which side had it in or out but thought it odd. This is why a guy needs to have a camera glued to his eyeball....

 

[953 nut 55,321]

3 minutes ago, pfrederi said:

Never have seen  a crank bearing with a shield.

Both of the engines were 1963 K-241 Spec 46135A from a couple 953s.

[Ed Kennell 38,227]

I guess I don't understand why there should be a shield on either side.       Logic tells me more oil  is better on a bearing and you certainly  don't want the seal to run dry.

[WHX?? 48,828]

Exactly Ed... any sign of someone being in the motor before Richard? 

Unless someone figured enough oil would get past the shield to lube the seal? 

Edited February 27, 2021 by WHX24

[953 nut 55,321]

2 minutes ago, WHX24 said:

Exactly Ed... any sign of someone being in the motor before Richard? 

No signs of either engine having been worked on previously.

8 minutes ago, Ed Kennell said:

I guess I don't understand why there should be a shield on either side.       Logic tells me more oil  is better on a bearing and you certainly  don't want the seal to run dry.

I'm inclined to turn the open side inward on both but wanted input from others on this. The shield apparently allows some oil to pass and there is a drain slot under the bearing. 

[WVHillbilly520H 10,373]

@richmondred01.

[Pullstart 62,912]

I vote shielded side out.. let that oil bathe the bearings from the inside!  

[roadapples 6,983]

@oldredrider???

[oldredrider 2,548]

Shield to the inside of block. Kohler says so. 

[richmondred01 2,237]

I replace them with open sided bearings however, the ones I’ve seen the shield faces out on the open faces in. 
The vast majority of these were on the Deere models. Don’t ask me why. 

[Herder 2,354]

I would guess the open side out may allow contaminants into the rollers and reduce bearing life.  Just my my thoughts.    

[WHX?? 48,828]

So why do some have it and some do not. All of the 241s and 301s I have built dId not have them. 

Any idea on year Richard?

[953 nut 55,321]

Both of the engines were 1963 K-241 Spec 46135A from a couple 953s.

 

[953 nut 55,321]

10 hours ago, oldredrider said:

Shield to the inside of block. Kohler says so. 

I have an older service manual in my shop and shielded vs. open wasn't mentioned but the manual we have in our manuals section says exactly what you are telling us.      

[richmondred01 2,237]

I know what the book says but everyone I’ve removed in 40 years the shielded side was out. 
that’s why I get new ones. 

Edited February 27, 2021 by richmondred01

[Ed Kennell 38,227]

Now I can add manual writers to my list of people I don't trust.....lawyers,  salesmen, doctors, politicians,....

[Gregor 4,846]

Why not simply remove the shield? Problem solved.

[richmondred01 2,237]

2 minutes ago, Gregor said:

Why not simply remove the shield? Problem solved.

I rather spend the 18-20 dollars and get a new one and be done with it for another 40 years.

Edited February 27, 2021 by richmondred01

[Gregor 4,846]

That's probably better yet. All that work, why reuse old bearings if you don't have to.

[Gregor 4,846]

When I rebuilt my 7 HP, I did reuse the old bearings. I don't have a press, and I have never been a fan of hammering on new bearings. I could have taken it to a shop, but that's 40 miles one way, and probably a 2 or 3 day wait. That means 2 trips. Reuse old bearings, or hammer on new ones with a punch. Theres the real ?.

[Ed Kennell 38,227]

      Could a single sided shielded bearing, due to the assembly process, have a higher axial thrust rating in the direction toward the shielded side????

 

        Any bearing gurus?

[Gregor 4,846]

32 minutes ago, Ed Kennell said:

      Could a single sided shielded bearing, due to the assembly process, have a higher axial thrust rating in the direction toward the shielded side????

 

        Any bearing gurus?

No idea, but.....I don't think there is much of any axial thrust on these bearings. I could be wrong. Have been before.

[JoeM 7,874]

1 hour ago, Ed Kennell said:

have a higher axial thrust rating

I am thinking not.....but I am thinking if installed with the shield in would retain more oil longer. I think it is easy to assume how the bearing gets oil and not thinking how it keeps it??