J Class Changes

[NW Mailing List]

610 also had its tandem rods replaced with single rods and larger hubs.

I believe part of the reason was the long crankpin on #4 axle drivers.  The new rods were closer to the surface of the drivers resulting in shorter crankpins and less bending stress.

Dave Stephenson


--- On Tue, 9/2/08, NW Mailing List <nw-mailing-list at nwhs.org> wrote:


> From: NW Mailing List <nw-mailing-list at nwhs.org>

> Subject: Re: J Class Changes

> To: "NW Mailing List" <nw-mailing-list at nwhs.org>

> Date: Tuesday, September 2, 2008, 7:37 AM

> The "extra" side rods were removed on three

> J's in their first life: 600, 

> 605, and 611.  Actually, the rods on these engines were

> completely replaced. 

> As I understand it, the reason had to do with a stress

> failure of some kind. 

> Check out photos of the various J's and you will see

> that the replacement 

> rods had much larger rod bearings on drivers 2 and 3.  I

> would call this an 

> ungrade applied as necessary, and only three engines got

> it.  611 was the 

> last of the three to get the new rods.

> 

> Also 611 in its second life had two generators installed

> instead of the 

> original one.

> 

> --Rick Morrison

>