Rejuvenation of con-rod alloy?

[Graham.Goral]

Hi all,

I've observed the discussion of Square Four con rods reaching an age when they're prone to failure, leading to us making the recent batch of new billet ones...

Given the fact that we're not remanufacturing KH con rods, is there anything i can do to reduce the risk of this happening to my KH rods before I reassemble the engine - like anneal them or something? Or, at least, can I identify if they're at the point where they're likely to fail?

Cheers
Graham

[nevhunter]

You can have them crack tested but they have a definate life. The alloy speedway JAP rods were recommended to be retired after a season, but they are run at revs close to blowing up anyhow.
I do get involved with a lot of heat treated alloys used in aircraft structures, but most of them are purchased in the final state. (already heat treated).
Do you know the specifications of the alloy used. Alloy spec and original heat treatment state.
The small ends get pretty hot anyhow and most normal heat treatment processes would be undone at the temperature they reach sometimes.
I have a few motors with steel rods that are blue for the first 4 cms. Someone will know what temp that equates to. I think they would start losing hardness at around 250 degrees C The alloy rods) but unless we know exactly what they are made from we are just guessing.
New ones would be nice. Some people I know use new ones in triumphs when they rebuild .Nev