C2 Aluminum Valve Cover Repair

[Ralph E.]

I was cleaning my aluminum valve covers today and discovered a small crack near one of the hold down bolts. It is a small crack, only visible from the inside of the cover. I would like to know if it can be repaired before things get worse. If it can be repaired will the repair be noticeable.

[Donald O.]

Re: C2 Aluminum Valve Cover Repair

The only way to permanently repair aluminum is to weld it by heli-arc. IMO, I'd replace with new.
Don

[Ralph E.]

Re: C2 Aluminum Valve Cover Repair

The valve cover has two small cracks where I must have over tightened. I hate to let this get away. They came with the car. Any thought about heli-arc welding on the inside.

[Clem Z.]

Re: C2 Aluminum Valve Cover Repair

to weld it you need to get all the oil out and that may be a problem.

[John H.]

Re: C2 Aluminum Valve Cover Repair

Jerry MacNeish ( www.z28camaro.com ) specializes in just this kind of weld repair for aluminum parts, and has done several for me that are exactly as you describe (common problem). While you're at it, have him re-skin them and they'll look just like new (link below).




Re-Skinned Corvette Valve Cover

[Tom Parsons]

Re: C2 Aluminum Valve Cover Repair

Over the years, I have had several finned alum covers repaired by welding. For sure, it does take a good skilled person to do a proper job of welding alum. But the real key, is in carefully working down the welded repair. The ones which I have had welded, I have worked the weld myself. It takes time, care and patience to make it look good. And sometimes, after the weld is worked down, pits develop (form oil/dirt in the pores) and it may need to be welded a second time and reworked. You can't always replace a damaged cover with a new one. For example, I have saved two pairs of 9-fin covers by having broken fins built up with weld and then VERY CAREFULLY working down the weld with a die grinder and sanding disc. PATIENCE, PATIENCE and then a little more PATIENCE! The pair which are on my 56 were purchased for $50 and considered to be nearly junk. Now, I defy ANYONE to find the repair.

[Ralph E.]

Re: C2 Aluminum Valve Cover Repair

Got my valve covers back all repaired. I had a welder do the work. He did a nice job. Problem is he sand blasted the covers to clean them up and make them look nice. How do I polish them to look original? He meant well, what can I say.

[Tracy C.]

Re: C2 Aluminum Valve Cover Repair

The factory finish was not polished however I think you will need to do it anyway. Look closely and you will see tiny pits caused by the sand. To correct this, you need to "wet sand" the cover with 400 grit paper and machine buff to a smooth and shiny finish. Then find a local company who specializes in media blasting and have them blasted with walnut hulls. This will knock down the luster of the buff job and return the correct "marbled" matt finish.

[Dave S.]

Re: C2 Aluminum Valve Cover Repair

There are vendors who reskin them and make them look better than new. Cost is about $100/pair.

[Tracy C.]

Re: C2 Aluminum Valve Cover Repair

Interesting...How is reskinning accomplished? I work in the Aircraft biz and the only process I can imagine is an acid dip (chem mill) This process is used to thin localized areas in aircraft skins. Do you know any such vendors?

[Dave S.]

Re: C2 Aluminum Valve Cover Repair

Terry,

I'm not sure how it works, but I'm told they have a machine that spins them and somehow the surface is made consistent. I had a pair done and they almost look to good, but with the current over restoration craze they would be perfect. I wasn't real pleased w/ the service I got from the vendor I used but I believe a fellow named Chuck Smith does them and from the feedback of others he does a nice job. I think you can find him in Hemmings.

[Ralph E.]

Re: C2 Aluminum Valve Cover Repair

If I machine buff the valve cover should it be done using a spiral buffing wheel with tripoli rubbing compound. Would jewelers rouge be better. I'm concerned with making them too shinny. The idea of using a buffing wheel and media blasting with walnut shells sounds pretty good. Has anyone tried this before?

[Tracy C.]

Re: C2 Aluminum Valve Cover Repair

I've never had to do valve covers myself but have seen the result. They turned out gorgeous! I suppose if you didn't have a buffer, (I bought mine at harbor freight, similar to a bench grinder but with extended necks for the buffing wheels to mount on) you could work your way into progressively finer grades of sandpaper. You could always give this a try without the buffing. Worst case is you would need to resand the covers and buy the buffer. You will find yourself using it for many other jobs anyway. I restored a pair of rocker panels in a similar fashion (wet sanding off the alclad and buffing to a brillant luster). No more road rash!! Just repaint the black stripes and clear coat them when done. You want red tripoli rouge for aluminumn and white compound for stainless.