Resurfaced lifters

[gzig5]

Novice question here. Dealing mostly with firearms….what about heat treating for hardness and using a process like black nitride or DLC for hardness and decreased wear? Black nitrided barrel
Bores have proven well for high volume high velocity projectiles.

I would think that they are heat treated when made, not just turned/ground out of stock and dumped in a bin, but who knows. The main problem is the base material now being used and/or the heat treat process. The radius on the ends of them is probably suspect as well. Something like nintriding might help life, but you still need good base metal and it will add quite bit of cost.

 

[Rat Bastid]

Bakerlite. Yep. I had lifters re-faced once by CamTech & they a 'point' in the centre, so I have been using Clive ever since, never had a problem & he gets a superb finish on the lifter.

Any chance you have a picture of the point on the lifter? It makes it easier to understand if you can see a picture of it.

 

[Phreakish]

Novice question here. Dealing mostly with firearms….what about heat treating for hardness and using a process like black nitride or DLC for hardness and decreased wear? Black nitrided barrel
Bores have proven well for high volume high velocity projectiles.

Nitride is mostly hype. If not for the EPA, no one would nitride barrels.

With regard to a lifter, nitride is too thin. Typically being .0004-.0012 max. Dlc is an order of magnitude thinner.

Nitride happens well above 1000 degrees, and so parts can and do warp. The thin shell doesn't leave enough meat to grind after heat treat the way a true case hardening does. Through hardening a lifter is asking for cracks or fatigue failure.

Dlc can work, but with soft substrates it's like using an m&m as a bearing. If the base material is hard enough, then you don't benefit from the Dlc. Mostly Dlc is used for corrosion protection and wear resistance for things like seals and wipers (think hydraulic rams and the like). It's also widely used on cutting tools, but those things are already made from woodpecker lips.

I'm willing to bet the majority of cam/lifter failures are due to lifters not spinning in their bores. Either due to an improper face geometry, or improper lobe taper, or bore prep. All three things can be inspected by the assembler, but rarely are.

 

[pishta]

Quite a few old Volvos and Porsche race motors resurface their hard to replace mushroom lifters. The Fiat performance shop locally quoted Mopar dumbell solids for $3 a piece as it takes about 30 seconds to do one. They have to use the proper radius grinder stone on a dedicated lifter grinder or a Sioux or B&D valve grinder attachment. Not sure how thick the bottom of a Hi-Energy lifter is to get reground, probably thick enough.

 

[1MeanA]

I read that mfg's had different radius specs. Perhaps the problematic lifters have the Chebby radius

 

[Bewy]

Rat,
Sorry no pics. I could feel 'the point' with my fingernail, so I knew it would be a lobe-killer. I actually had these lifters re-faced by another company & all good.

 

[Bewy]

Post #26.

The FT lifters we are talking about are cast iron. It is the same hardness throughout & no heat treatment needs to be done after re-surfacing.