mcculloch rod bolt post

[Kurt Bogerman]

http://www.usmotorpower.com/parts/intern...s-set-of-2

[doug tenney]

This is an old thread (no pun intended!)... but I figured I'd throw this out... M5X0.8 (metric) screws happen to be virtually identical to the #10-32UNF that Mac's and WB820's use.
Maybe there's some super-duper 18,000 rpm foreign motors using that size?
I realize that motors with built-up cranks don't even use rod-bolts, but maybe some do.

These aren't super-duper, but just to describe what I'm referring to: https://www.mcmaster.com/#metric-socket-...s/=1c7k9oh
McMaster-Carr 91290A242

[jeff brown]

K precision is the guy who works at US motor power.

[steve welte]

When contacting bolt manufactures they will tell you that no bolt that is correct for our use is currently made. So prepare yourswelf for a lot of destroyed Fan cooled engines. When we were trying to get ARP to make them the problem became that you have to purchase large amounts of the meterial to produce a small run of bolts so the manufacture ends up stuck with a meterial that he doesn't have an immedialte use for. That creates a very high price for the bolt. The general public or manufacturing doesn't require a bolt that we need so it doesn't exist. Some will say use this bolt or that but at some point using a 180K bolt will mean you WILL pay the piper sooner or later. For now rebuilding fan cooled engines is dead unless you have an old stash.

[ted johnson]

Is USMP no longer selling the 260KSI screws? I realize the price is horrible, but to save a good block it's worth it. TJ

[doug tenney]

Here's the link: http://www.usmotorpower.com/parts/internals

Conn rods with bolts are $122 and In Stock shows as 100.
High-Strenth Bolts alone are $62.50, but In Stock shows as 0.

I don't know what bolts come with the $122 rod.

[ted johnson]

Ya pays yer money and ya takes yer choice. As cheap-a$$ as I am, I will not risk a rare or expensively (in time OR money) modified block just to save the price of a rod and bolts. BTW, I seriously doubt that you get the $62 screws AND the good rod for $122. I may be wrong, but I'd guess that the good screws are optional. TJ

[doug tenney]

My Mc91B had the elusive spline-head rod bolts.  I know because they were part of the shrapnel that punched it's way through the block at the beginning of last season.  Box muffler, dry clutch, mild gearing... but there I was, WAAAAAAA*CHUNK*, then gliding through Oreville's sweeper, like someone had turned off the sound at a Led Zeppelin concert.  I'd run it for a few years but never had it apart to freshen it up and check things out, so shame on me, and who knows, maybe the bolts were innocent.


ANYWAY, could someone please open their Diebold vault, pull out one of their US820 Unobtainium bolts and measure it for me?
SAME, for one of the elusive spline-head McCulloch bolts.

For both, I'd like to get:
A)  the head height
B)  the diameter where the head touches the rod cap (i.e., the diameter of the head or washer-face)
C)  the length (measured from under the head, to the end)
D)  the length of the UNTHREADED portion (if it's fully-threaded, then this will be zero)

If you don't want your buddies to find out that you have a stash of these that you forgot to tell them about, then PM the measurements to me.

Then at least I'll know what I'm looking for.
Thanks!
Doug

[steve welte]

You do not get the good bolts in the new West Bend rod.

[ted johnson]

Thanks, Steve. I didn't see how USMP could sell both for that price. Ted