Is this main bearing no good?

Cox Abele

Registered User
I'm in the middle of putting a 3.8L together and am right in the middle of plastigauging the mains. The first one went in great and mesured a bit loose, but still in spec.

Onto the second main. The upper (block side) snapped into place and centered just fine. When I looked at the lower (cap side) it doesn't look like the notch is centered like the other 19 bearings (used and new). For the sake of a better visual I loaded the cap onto the crank and took a picture. You can see the bearing sticking out. I don't think I have feelers thick enough to read the distance between the bearing and the counter weight, but I'd say it sticks out roughly 1/32 of an inch from the cap.

bearing.jpg


The crank was polished and the bearings are new. Cutting the bearing isn't an option, I might as well buy a new bearing kit if thats your answer. I just don't see this being right.
 
Once you figure out if you have the right Main bearings you should plastigauge them and check the specs.... you have it down this far make sure the tolerances are correct...
 
I do have the correct bearings. The shop that polished the crank for me also ordered my bearings after miking them. I was plastigauging everything when I found the problem.

This is #2 cap. Thrush is on #3.
 
It is often necessary to re-notch the block for proper bearing alignment because Ford had a habit of moving the notch around.
 
What brand bearings are you using?

clevite

The cap shouldn't need to be re-notched. The notch is dead center. If I were to put any other bearing in it, the bearing would sit centered in the sadel. The notch in the bearing is not centered in this particular case causing it to stick out from beyond the main.

The lower (oil feeding) bearing is sitting in the block dead center, but this one however is not, which has me worried about proper oiling and possible scaring of the crank.

For a better idea of what I'm dealing with look at the following picture. This is not my bearing, but I used the pic in order to illustrate my problem. All of my bearings have the notch where the green line is. This causes them to sit centered in the sadal. The bearing in question however is notched where the red line is, thus causing it to stick out further.

224695.jpg


Only Pap has said that this is ok, and not to distrust his wisdom, but I'd really like to have a "no contest" agreement on if this bearing is still good or was bad from the clevite factory.
 
In the Sealed Power product application guide it says "it may be necessary to notch the block or main bearing caps for correct bearing alignment." Clearly the bearing manufacturer's are aware of Ford's inclination to move the notches around. Being that I build my fair share of these motors on a daily basis I can attest that the notches are not always in the same place. However, I can also say that most often the Sealed Power bearings fit better than the Clevites do.

Also, make sure you are not trying to put the #4 bearing into the #2 slot. It's a different size....
 
In the Sealed Power product application guide it says "it may be necessary to notch the block or main bearing caps for correct bearing alignment." Clearly the bearing manufacturer's are aware of Ford's inclination to move the notches around. Being that I build my fair share of these motors on a daily basis I can attest that the notches are not always in the same place. However, I can also say that most often the Sealed Power bearings fit better than the Clevites do.

Also, make sure you are not trying to put the #4 bearing into the #2 slot. It's a different size....


ok, so notching the cap is an option, but how can this be done? If my machine shop does it, the time I have to take from work and then their price will probibly outweight the cost of a new set of bearings. If it can be done with a grinder than I could handle that.

Regardless, this bearing is still stamped/notched different from the other 15 that I have (the new set being installed and old bearings removed from engine). The numbers do match however... I have four new 3187, two with oiling grooves and 2 for the lower cap assembly. And yes, I have already set aside number 4's .010 undersized bearing.

Not to disagree, but I really don't believe the block/cap can be the issue. This one bearing's notch doesn't match any of the others (all of which are notched in the center). "one of these things does not belong here" kind of thing.
 
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Is this for a NA 3.8? I just went through this also and had the wrong main bearings. Same thing, the notches were on the side and not in the middle. Make sure you know what year block you have as it will read like this, say you have a 89 block it will read E9. A 94 block will read F4 as the first 2 digits.
Ford goofed around with bearing types. Note that some of the berings will be differnt from the front to the rear. Also make real sure nothing is on the mateing surfaces or under. A speck of dirt will throw off the mesurment.
 
ok, so notching the cap is an option, but how can this be done? If my machine shop does it, the time I have to take from work and then their price will probibly outweight the cost of a new set of bearings. If it can be done with a grinder than I could handle that.

Regardless, this bearing is still stamped/notched different from the other 15 that I have (the new set being installed and old bearings removed from engine). The numbers do match however... I have four new 3187, two with oiling grooves and 2 for the lower cap assembly.

If you have an air cuttoff wheel that works great. It will make a nice 1/8" notch in seconds. I've given up trying to figure out the notching system and just "Git er done".
 
Try and get some better pic`s up with just the bearing in the cap, new and old. also try and fit them in differnt caps. I see now what your talking about. Will the side of the bearing rub the crank or will the thrust bearing keep it from rubbing?
 
Is this for a NA 3.8? I just went through this also and had the wrong main bearings. Same thing, the notches were on the side and not in the middle. Make sure you know what year block you have as it will read like this, say you have a 89 block it will read E9. A 94 block will read F4 as the first 2 digits.
Ford goofed around with bearing types. Note that some of the berings will be differnt from the front to the rear. Also make real sure nothing is on the mateing surfaces or under. A speck of dirt will throw off the mesurment.

Actually, the 94+ blocks had an F1 casting number.

The 3187 bearing that he listed is the right one for the front bearings, I think the rear one is 3188. The NA 3.8 uses the same bearing as the SC except journal #4 so no worries there. Like I said before, I've seen the notches all over the place. I've had thrust bearings that won't fit the notches at all as well.
 
Dave, if the notch is just a little off like a 1/8 and you try to make it bigger wont the bearing move around?
I seem to remember some bearings do stick out just a little and dont fit the caps or block perfect. For a NA motor I would not worry but for SC`s have have sent the bearings back untill the right set came in. Same part numbers too:eek:
 
Dave, if the notch is just a little off like a 1/8 and you try to make it bigger wont the bearing move around?
I seem to remember some bearings do stick out just a little and dont fit the caps or block perfect. For a NA motor I would not worry but for SC`s have have sent the bearings back untill the right set came in. Same part numbers too:eek:
The reason that there are so many variations is that Ford changed the notch locations several times. I think now the aftermarket is confused and is sending out bearings with random notch locations.

The notch locates the bearing during assembly but does not hold the bearing in place. The bearing is held in place by the crush applied to it from the bearing caps. The bearing and housing bore is an interference fit.
 
Thay makes sence. Its just that I am so picky when it comes to this stuff. I hate to do things twice. My parts store hates me as they have sent alot of stuff back for me. Your right about the F1 nubers for the 94`s as Ford liked to season their blocks before they went into the cars but I do see some slight changes from E9 blocks to the F1`s. A little off topic and im sure you are asked this alot Dave but what is the easyest years to tune? 89-09
91-93 or 94-95. I only ask this because I loved my 94`s but they seemed to be the most finnikey cars and never ran the same from day to day and I cant help to think it had something to do with the updated electronics and or tune.
 
Try and get some better pic`s up with just the bearing in the cap, new and old. also try and fit them in differnt caps. I see now what your talking about. Will the side of the bearing rub the crank or will the thrust bearing keep it from rubbing?


Nope, there is plenty of clearance between the bearing and the counter weight. If I loose thrush tension from the number 3 bearing, the motor is toast anyhow. th......




Wait... I just said ~~~~ it and took the grinder to the cap. Problem solved:rolleyes:
 
Thay makes sence. Its just that I am so picky when it comes to this stuff. I hate to do things twice. My parts store hates me as they have sent alot of stuff back for me. Your right about the F1 nubers for the 94`s as Ford liked to season their blocks before they went into the cars but I do see some slight changes from E9 blocks to the F1`s. A little off topic and im sure you are asked this alot Dave but what is the easyest years to tune? 89-09
91-93 or 94-95. I only ask this because I loved my 94`s but they seemed to be the most finnikey cars and never ran the same from day to day and I cant help to think it had something to do with the updated electronics and or tune.
The 94 has higher compression which seems to make it more sensitive to heat. Because of this (I'm assuming) Ford made the parameters which control ignition timing and fuel more aggressive. In the right conditions a 94 can still run really good but most of the time they were doggish for this reason.
 
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