Main Bearing Clearances

[DanielB23]

This is an update to my previous post about possible tight bearing clearances. Both the camshaft and crankshaft had an abnormal amount of resistance when trying to spin them after they were installed using Permatex ultra slick.

Yesterday I took out the crankshaft and cleaned all the Permatex off the journals and bearings. I placed the crank back in and measured my clearances with a strip of plastigage on each journal. Here are the measurements:
Cap 1: .0014 - .0015
Cap 2: .0014 - .0015
Cap 3: .0015 - .002
Cap 4: .0014 - .0015
Cap 5: .0015 - .002
I estimated ".0014 - .0015" because the mark may have juuust barely been wider than the .0015 marking on the paper. Are my clearances going to be too tight? Do they vary too much?

Specs from Haynes manual:
Main Bearing Journal - Bearing oil clearance .0008 to .0015 inch

However, everything I have found on the internet basically states .0015 is pushing the tight side and you really want to be around .002 instead. This crankshaft was balanced with the rotating assembly but I don't believe it was align honed.

I also noticed a couple minor scratches on some of the main journals. Not sure if these were pre existing or not. Some could BARELY catch my nail, but I know one of the scratches (the most noticeable/deep) was already there after the crank was polished. Should these be a concern?

 

[410Fortune]

It’s in spec

The grooves don’t catch your fingernail

It should take 35 psi approx of power to rotate the crank with oil coating and bearing torqued (according to @CDW6212R )

Why are you starting a new thread? This should be posted in your other thread to avoid confusion

What does the machine shop that did the work say?

Plastigauge is good but it’s not 110%
There are lots of variables here
I suspect you suspect there is something fishy going on.. otherwise you would have just put it all together. So if you think the tolerances are too tight my first call would be to the machine shop

 

[Josh P]

I don't believe it was align honed.

I looked at the other thread, and am wondering if you marked where the caps went?

 

[DanielB23]

It’s in spec

The grooves don’t catch your fingernail

It should take 35 psi approx of power to rotate the crank with oil coating and bearing torqued (according to @CDW6212R )

Why are you starting a new thread? This should be posted in your other thread to avoid confusion

What does the machine shop that did the work say?

Plastigauge is good but it’s not 110%
There are lots of variables here
I suspect you suspect there is something fishy going on.. otherwise you would have just put it all together. So if you think the tolerances are too tight my first call would be to the machine shop

I think I was just overthinking everything. My clearances were all good after checking with plastigauge, I made sure to clean my bearings and journals thoroughly, and tried not to overuse the assembly lube. The crankshaft spun by hand noticeably easier than beforehand. It's possible I over torqued one of the main caps or didn't set the thrust bearing properly the first time. Maybe I just used too much permatex. Regardless, after checking all bearing clearances and knowing they are in spec, I now have peace of mind.

Made two threads on accident, just wasn't thinking. Onto installing the pistons now

 

[410Fortune]

It is easy to over think this stuff because we want so much for it to be correct after all this labor!!