Ok I got a ticking noise in my 406, so after I tracked it down, it ended up being a wore out cam lobe. I got another cam and I was told the reason the cam lobe was wore, was becasue I broke the cam in with double springs. They said I should have taken out the inner spring and broke it in that way. Has anyone ever heard of breaking a new cam in that way??????

 

http://www.compcams.com/Technical/In.../Files/145.pdf

After Step 12, it says this:

"Camshaft Break-in Procedure
Important: On hydraulic and mechanical (solid) flat tappet cams that require dual valve springs, the inner spring must be removed during break-in."

 

I know it says that, but that is alot of trouble to do that on the car. I just don't see how running an engine for 20 to 30 minutes with the inner springs out is going to make. Your just going to put them right back on after that. I guess I just don't see why that would make a difference.

I guess I should have said the old cam had the back lobe wore down, I still think I got a bad cam out of the box.

 

There has been alot of talk over the last few years because of cam failures being linked to low sulfur and zinc content in our motor oil. There are alot of thoughts how how to prevent this. Do a search and you can learn alot.

 

The idea of the break-in is to allow the lifter to spin in the bore so it doesn't create a lobe pattern on the heel of the lifter. Heavy spring load during or without break-in can prevent that spinning. Same reason you aren't supposed to use synthetic oil during break-in.

When I installed my last flat-tappet cam, I talked to a fellow racer who runs an engine shop. He tossed me a packet of ARP thread lube and said slather the lobes and lifter heals with that stuff, do the break-in with petroleum oil, then change the oil. Said he's never removed center springs, and has never wiped out a cam.

Also understand the issue lately with ILSAC GF-4 oils and reduced anti-wear additives. Use of a dual diesel/gasoline rated oil is suggested, as the diesel oils still have those additives. As long as it has an SL rating along with the CI-4, it will be fine.

 

Kendall gt1 20w-50 is the only motor oil still out with a SL certification for high zinc content. Also the diesel oils, eg: shell rotella t 15w40 and chevron delo 400 15w40 (the older version that isn't low emission), will have a high content also. If you choose not to run any of those oils then you could try a bottle of the GM EOS part# 88862586.

 

Not true. AMSOIL has several diesel oils with the anti-wear additives, with both CI-4+ and SL ratings.

EOS is for assembly and run-in only. It is not intended as a running additive.

 

EOS is sold to be used as a running additive as well. To "quieten lifter noise" etc etc. I would use that as an additive with "normal" oil, since I can't figure out which oils have the right additives for my motor anyway...

Yea, wiping a cam when you left in both springs sounds about right. Yea it's a pain in the ***, but so is making sure you torque up all your cylinder head bolts in order, and go over them twice. But hey, you do that don't you? And then you don't have any head gasket leaks either

 

Not by GM.

 

I'm just going by what it says on the bottle... I figured GM wrote that..?