[tom s]

Aftermarket cranks are famous for having a large radius.They make narrow rod bearing for them.As said I had a slight issue with a rear main when I took a engine down.The very back was in the brass but nothing like this.Was never enough to even feel it when the crank was turned without the seal.Just something to be aware of when using aftermarket cranks.When I got there today all the caps were off.Im sure the seal was toast with the heat that crank and bearing saw.Tom

[Baron Von Zeppelin]

Yeh it roasted the 1 piece rear main seal.
A little surprised it didn't make an oily mess back there with it being out of commission ?
Maybe some of the desintegrated seal debris plugged up some oil flow.

Something caused #4 thrust to turn in the cap
And then there's the scuffing in the cylinders that might have been lack of oil

... and the spark plug gaps that are another enigma unto themselves.

Im sure Mike will get some more info for us next week as he is REALLY interested.tom

That is really great to hear he is taking high interest in it.

[tom s]

I tried to post a pic of the block saddle but wont post for some reason.The seal just melted out of it.The clevite left a imprint in the saddle that you can feel with your finger nail.Maybe it will show up as I did the down load like I did the rest.Im sure Mike will get some more info for us next week as he is REALLY interested.tom

[tom s]

The 4 cap did not turn!Optical illusion !All other bearings are fine.Tom

[tom s]

Try one more time.

[Baron Von Zeppelin]

Dabgummit . lol
In Napier's pics before disassembly, and your pics after crank removed - it looks to be turned out of index in all those pics. (#4 thrust)

The other shells in your pics are still indexed proper.
You got me !
victim of circumstance and opticals !
The #4 surfaces didn't really look bad - i believe you

[tom s]

There you go!

[KEN CROCIE]

mysteries to be solved:
plug gap
chipped cam gear
post # 75. valve pocket placement. looks to me that the valve was hitting the edge of the pocket.
what caused #5 to get so hot.

[tom s]

The hone was all the way through!Tom

[lust4speed]

I take the "finished" cranks from suppliers to the machine shop and pay for their inspection. I've had several reports come back with journal taper and one bent crank. Don't get me started on problems with rods and pistons that either I have found or the machine shop found on their inspections.

To quote Ken Crocie, "We are now the quality control inspectors".

Reference a previous posted photo that I enlarged - is the seal contact surface tore up as much as the photo makes it look? If so, could the seal friction heated the rear of the crank enough to take up clearance and seize the bearing?

[tom s]

Mick,we will know more when Mike can get into it.He is having to shoe horn this in between jobs he already had going.One is my 383-301 engine.Tom

[ponjohn]

Any updates?

[wbnapier]

Originally Posted by ponjohn

Any updates?

I spoke to the machinist on Friday. He had just received a new set of main bearings that he needed to make a couple of tests, specifically a new #5 bearing. He said he'd do those today or tomorrow and let me know.

His goal is to get some specific measurements on the radius fillet, bearing width, bearing chamfer, endplay, interference, etc... before I contact Butler and Scat.

I read through the warranty info on Butler's and Scat's website and don't see any meaningful recourse based on the specifics of their written warranty, assuming I can demonstrate a clear manufacturing error.

Let's say Butler/Scat acknowledge an error, what can I expect?

After this, I'll get a quote, soup-to-nuts, on a long block and evalauate what I can swing.

I will post on this thread as soon as I get an update.

[MarkS57]

Originally Posted by wbnapier

I spoke to the machinist on Friday. He had just received a new set of main bearings that he needed to make a couple of tests, specifically a new #5 bearing..

Hi did he say which mains he ordered? Should be what came with the stroker kit.

[tom s]

I think he was ordering at least a couple brands.He was going to get a set of Clevites but wont run them.Tom

[johnta1]

Probably needs mains (and rods) for a large filet crank throw?
I always had to special order them? (used a different number for them than the standard type of bearings)

[wbnapier]

Originally Posted by johnta1

Probably needs mains (and rods) for a large filet crank throw?
I always had to special order them? (used a different number for them than the standard type of bearings)

Yes, the bearings came with the stroker kit, Clevite, either P or H I think.

I'm assuming he could look at what came out vs. what he has in hand and compare them.

[tom s]

John,I have been able to find rods but have not found mains that are made for a large radius?Tom

[geeteeohguy]

Originally Posted by tom s

John,I have been able to find rods but have not found mains that are made for a large radius?Tom

You can use an old fashioned bearing scraper or a file or even a sharp knife and dress down the side of the bearing to clear the filet on the crank. I just did this last year when assembling my 383 SBC. The machinist showed me the trick when he sold me the bearings......it takes a little time, but the upside is more bearing material supporting the rod or crank than the thin 'race' bearings supply. YMMV...

[many birds]

I’d never heard of King bearings when I was assembling my ‘68 400 stock crank engine. I was initially considering clevite. For whatever reason that I don’t remember, my machinist recommended king, and now 8k miles later, no problems.