Should valve spring retainers be hardened?

[scott12180 35]

I'm working on a 1926 Packard Eight.

I need to make new valve spring retainers and keys for the slotted valve stems because the original ones were discarded by a previous owner.

Do I need to make these spring retainers and valve stem keys out of hardened steel, or can they be non-hardened steel? SHOULD they be NON-hardened?? MUST they be hardened?

I bought the keys from Egge but am surprised that they are a very soft steel.

Our machinist thinks there is no need for the retainers and keys to be hardened because there is no movement between mating surfaces. Only inertial loading. A friend in the restoration business thinks they should all be hardened.

Any opinions?

--Scott

PS: The original Packard spring retainer (the only one I have) appears not to be hardened.

[Bhigdog 3,110]

Here's my opinion. Hardened steel is used for wear surfaces, so there is no need for hardening and in fact it might be a negative because hard steel is brittle. The ideal materal would be a tool steel that is hardened and then tempered to a spring or "tough" temper. A good compromise would be for you to have your soft steel parts case hardened. That would give them a hard "skin" for wear with a soft core for toughness........Bob

[nearchoclatetown 306]

Don't guess. There should be a supply of used or NOS retainers and keys out there somewhere. Racers use aluminum retainers so I doubt yours were hardened, but of course their's don't have to last 100000 miles. Just an opinion.

[DizzyDale 0]

Dear nearchocolatetown,RACERS use titanium retainers and valves.NEVER had a problem,over.800 lift cam and sometimes 10,000 rpm..diz

[nearchoclatetown 306]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Don't guess. There should be a supply of used or NOS retainers and keys out there somewhere. Racers use aluminum retainers so I doubt yours were hardened, but of course their's don't have to last 100000 miles. Just an opinion. </div></div>Dizzydale, I guess I should have said "some racers", unless you want to dispute the Summit catalog. They show part number DCC-4529823 as being an aluminum valve retainer. The point was that they need not be hardened. I wasn't trying to exclude other metals.