Fxing pits on aluminum water fittings

[TomoHawk]

After removing the radiator hoses, I found pits on the aluminum inlet & outlet ports. Is there anything better than JB Weld to fill the pits? Anything that can be polished maybe?

thxZ

Edited December 7, 2009 by TomoHawk

[d240zx2]

Why not replace them?

[g9m3c]

After removing the radiator hoses, I found pits on the aluminum inlet & outlet ports. Is there anything better than JB Weld to fill the pits? Anything that can be polished maybe?

thxZ

Well, if they are, in fact, pits (metal completely missing from corrosion), then polishing will do nothing to repair them. JB Weld would definitely not be one of my suggestions for a repair, either. Since they are cast, I wouldn't suggest welding. Replacement looks like your only option for a correct, permanent solution.

MSA doesn't list either of these parts for your 280Z.

http://www.thezstore.com/page/TZS/CTGY/SCC06

Black Dragon doesn't have either of these parts listed in their catalog, either.

Z Car Source has them listed but you have to call to get pricing and availability.

http://www.zcarsource.com/content/p/9/catid/7691

I hope this helps.

Edited December 7, 2009 by g9m3c

[TomoHawk]

You'd have to fill the pits with something before polishing. I think I have some aluminum alloy soldering rods somewhere that might work.

Edited December 7, 2009 by TomoHawk

[g9m3c]

So, I'm guessing the pits are not just under where the hoses were?

[TomoHawk]

Yes, the pitting is under the hose, on both parts.

BD has the parts in the paper catalog, Z.60, pg 77.

thxZ

Edited December 7, 2009 by TomoHawk

[FastWoman]

Tomo, I don't know about JB Weld, but some epoxy/filler products (especially the epoxy putties, and even polyester/filler products like bondo) absorb water and swell. I remember making some very nice sump pump assembly mounts that were secured in the bottom of the bilge compartment of one of our boats with epoxy putty. The mounts failed within 2 years, having swollen and crumbled. If the pitting isn't too deep, and if all you need is to halt the pitting process, I'd suggest just cleaning it up and coating it with straight epoxy. I've found the stuff to be pretty durable on our boats. I would only do this on the outside surface of the hose barb, though. Epoxy applied inside the housing could potentially flake off, travel, and lodge somewhere else.

On another note, do you keep your antifreeze changed out at proper service intervals? It gets corrosive if it sits in your system too long, with breakdown products building to the point that the additives can no longer neutralize them.

Edited December 7, 2009 by FastWoman

[TomoHawk]

The pits are only on the outside of the fittings.

I'm changing the coolant annually, until it starts looking like there's no rust in it.

I'd rather repair (and retain) the original parts, if possible, rather than buying new everything at the first sign of deterioration. Since the pitting is hidden, I think repair is possible. The exposed areas only need some light sanding with medium or fine steel wool and polishing. the same with the steel fittings.

thxZ

Edited December 7, 2009 by TomoHawk

[FastWoman]

That's what I'd do, then. Epoxy can be pretty tencacious stuff if you have good surface prep. For instance, we had a huge rusting problem on our power boat's crank pulley. The roughness was chewing up our belts in short order. It's a Chrysler Marine 318, so parts are expensive and hard to find. I finally tried giving it an epoxy finish a few years ago, and that's worked perfectly since then. We use West Systems epoxy, available in many places, including West Marine (no relation between the companies). Any formulation without filler should do the job, though.

[ZCurves]

If the pitting is shallow AND external, then I would polish and then seal with a clear sealer like Eastwood Diamond Clear Gloss. I have used it on the exact same part you are talking about and no problems! This is not spray paint clear, it can stand up to high temps and all kinds of chemicals.

Good Luck.

Andrew

[g9m3c]

The pitting is under the hose, on both parts.

BD has the parts in the paper catalog, Z.60, pg 77.

thxZ

Are we looking at the same diagram?

http://www.blackdragonauto.com/icatalog/z/full.aspx?Page=77

If so, your year ('78?) is not listed for either of those parts.

[TomoHawk]

It's missing the heater inlet for a '78, and the bypass pipe & fittings for a '78.

Edited December 7, 2009 by TomoHawk