Sand blasted Valve covers- cause for concern?

Skip Newsom · 10-18-2003, 05:26 PM

I'm begining my winter P-car projects and upgrading to turbo valve covers on the lower sides is first up.
I ran a heavy dose of techron through, drained the oil, set valves (all were loose, hope i picked up a couple of ponies) and sand blasted the top covers as well as the new turbo lowers I picked up from our host... I decided to have them all powder coated as close to the signal yellow body color as possible.
While inspecting the top ones I found a small crack.
So the question is, do I continue and powder coat, or do I replace the top covers too???

The crack only goes about 1/3 of the way through the cover...

Rot 911 · 10-18-2003, 05:32 PM

No question that crack is going to get worse. Get new ones, they aren't that expensive.

mr914 · 10-18-2003, 05:46 PM

If you have a buddy that is a machinist. I'd tig weld it and mill it smooth.

No machinist buddy (6-pack standard), buy a new one.

Randy Webb · 10-18-2003, 06:22 PM

get some from eBay. But if/when it fails it won't be a catastrophe.

maxnine11 · maxnine11's Garage

not affiliated etc. etc.

used valve cover auction
max

makaio · 10-18-2003, 06:40 PM

I second picking up one or a set from e-bay. I've seen them go for under $10 a piece.

88911coupe · 10-18-2003, 06:55 PM

JB Weld? Maybe someone could explain why that would not work...

CARRERIC · 10-19-2003, 03:46 AM

I just bought a new set of upper valve covers for my 75 911 rebulid. Cost me $300 at Porsche. The old ones were not flat, which is the problem with buying used ones sight unseen.

makaio · 10-19-2003, 05:13 AM

To flatten them, you just need a sheet of 180 or 220 wet/dry sandpaper and a very flat surface.

ChrisBennet · ChrisBennet's Garage

Looks like someone cracked when overtightening them. As long as they're flat I don't think it will leak. The top covers only get exposed to a mist of oil - they don't have sitting oil on the seam like the bottom overs. Even if it cracked all the way through I'd just make sure the crack was on the high side of the valve cover. The nuts only need to be tightened to about 7 ft/lbs. Call me frugal. Replace the covers if and when they leak.
-Chris

Skip Newsom · 10-19-2003, 01:32 PM

I welcome the input!
I'm pretty frugal too and because it's an upper cover, still nice and flat, plus away from the area that actually needs sealing I'm on the fence about replacement.
Pelican has turbo uppers for $137.50 each! ouch, that would cut right into my carpeting budget...

350HP930 · 10-19-2003, 01:39 PM

If the crack is only from the hole to the outer edge of the cover I would just give them a light filing to make sure they are flat and use em.

Early_S_Man · 10-19-2003, 01:48 PM

Skip,

I would replace your Mg top covers with new aluminum covers as I did. The problem with used is you never know the condition, and risk getting a set of junk parts!

The new upper covers weren't called 'turbo' covers in my recollection, and they were only $48 or so, each, about six years ago.

My reason to replace the Mg ones was strictly due to the difficulty in painting Mg!

john70t · 10-19-2003, 01:51 PM

88911coupe: JB weld melts with heat and couldn't stick to the expanding/contracting surfaces I guess. I patched a cracked radiator with JBweld and fiberglass mesh but it only lasted a month or so.

speeder · 10-19-2003, 03:19 PM

That is a nothing crack in a nothing place, plenty of meat left there. Just don't overtighten them and you will be fine for another 50 years. Top covers never leak, and if they do it isn't much.

AFAIK, there is no such thing as "turbo" upper valve covers, turbos use the same upper covers as all nine elevens, and used are as good as new if not damaged. Should be $10-$20 each.