Rod bearing crush too much?

[shoe]

While sizing rod bearings I was checking crush and I think it's a bit much.

Big end is 2.086" bearing is a steel backed shell.
I torque both bolts to 18 ft/lbs then release one.
I am measuring with a feeler on the loosened side .008" with 2 rods at .010".

Clearances are all where I want them.

[mag2555]

What engine is this?

[shoe]

Engine is a BMW S54

[shoe]

I should add that the rods are of an established aftermarket brand.

[turbo camino]

Never heard of measuring bearing crush like that... is that an actual thing somewhere?

[swampbuggy]

In what manner did you determine that your clearances are where you want them ? Mark H .

[BillK]

Shoe,
I have never heard of the method you are describing. How are you measuring the big end bore ? It should be between 2.0866 and 2.0871 with the bolts torqued.
Also like Mark said . . . how are you measuring your clearances ?

[Warp Speed]

Never heard of measuring bearing crush like that... is that an actual thing somewhere?

Measuring bearing crush is done in the manner the op described, although checking torque varies.

[shoe]

All clearances are being verified with a mititoyo dial bore gage and Mititoyo micrometer.
Big end of the rod is in fact 2.0866". I dropped the last digit in my original post.
That is the dia listed on the card and verified via mic and dial bore gage.

That method of checking crush was recommended to me by a manufacture of rods a number of years ago.

Some years ago I assembled an engine using like components that had a rub at the base of the locating tang.
The post mortem discovery came to excessive crush. In that case the crush was .012" via the above method.
I believe it's a stackup of the rod BE at the low end of the tolerance and the race bearing adding crush.

It seems like this is an area of engine building that there isn't a lot of discussion about.
I may see about having the BE hone .0003" to bring the tight ones in line with the rest.

[engineman1642]

Is there another way?

[bentvalves]

does the steel backside of the bearing have some type of flash coating rust preventative measure applied, or is it bare metal?

a lot of times they are processed with something or other.

who is the bearing manufacturer?

[modok]

Sounds like too much crush imo.
We have discussed this a few times before. I can search for you later if you are not finding it.

[shoe]

I had done a fairly broad search prior to posting this.
But any additional information is greatly appreciated.
I've reached out to the bearing manufacturer and am waiting a response from engineering.

For many years I had always just done a thumbnail check to make sure the shell was proud, until I got bit.

[modok]

My comment about it being discussed in the past was mostly aimed at the other posters, but in any case here is what I found googling myself briefly.
hmmm, that sounds wrong LOL
viewtopic.php?t=49678
viewtopic.php?t=53428
viewtopic.php?t=52916

[shoedoos]

where did the 18 ft/lb come from?