OK, I had a little time today (thanks to an ice storm that closed my office...) to tinker with an old carb. I found a suitable victim, some variety of TQ that wasn't too dirty - I didn't want to get out in to the sleet and 20-degree temps to clean the thing first, so this one is fresh out of the bin.

Carb_Restore_Baseline-01 by clair_davis, on Flickr

Effort will focus on the driver side, and this is the general texture I'm hoping to keep. I need to verify that the AVS is about the same - I kind of remember it being a little more coarse than this TQ:

Carb_Restore_Baseline-02 by clair_davis, on Flickr

The bottom side of the body is essentially as-cast and nice, bright, and fresh. This is the look that I suspect the whole carb used to look like, and what I remember my NOS TQ looked like when I took it out of the box:

Carb_Restore_Baseline-03 by clair_davis, on Flickr

I'm using blue tape to mask the areas that will be treated:

Carb_Restore_Baseline-04 by clair_davis, on Flickr

First up, Eagle One etching mag wheel cleaner - works great on my as-cast Vintage Wheel Works wheels, and I'm expecting it will work OK here. This bottle is almost empty and several years old, so it may be a little weak due to age.

Carb_Restore_Eagle1-05 by clair_davis, on Flickr

Still foamed up as the aluminum reacted with the phosphoric acid. I finished everything with a worn-out toothbrush to scrub the nooks & crannies:

Carb_Restore_Eagle1-06 by clair_davis, on Flickr

And done... not very dramatic from this view:

Carb_Restore_Eagle1-07 by clair_davis, on Flickr

Up close, you can see that it's now clean, but it does have a darker tone as noted above. Texture appears to be 100% intact:

Carb_Restore_Eagle1-08 by clair_davis, on Flickr

Here you can see that this anodized plug does get slightly discolored, but you could probably mask this off to avoid any damage:

Carb_Restore_Eagle1-09 by clair_davis, on Flickr

Overall, I was pretty happy with how the Eagle One etching wheel cleaner worked. The resulting finish had the right texture, but it was a little dull, and not as bright as I would like.

Next up, crushed walnut shells in the blasting cabinet...

Clair

Keep us posted with your results. One other thing, how were you able to put up more than one picture in one post?

The walnut shells are pretty big as far a blasting media goes:

Carb_Restore_Walnut-10 by clair_davis, on Flickr

My blasting setup isn't ideal for them, the compressor is on the small side, but I'm running it at about 50psi to keep from being too aggressive right off the bat. Here's the cabinet and gun, just a cheapo siphon hopper I got at HF, and it holds about a quart of media.

Carb_Restore_Walnut-11 by clair_davis, on Flickr

The walnut shells did a job on the tape:

Carb_Restore_Walnut-12 by clair_davis, on Flickr

But it did a job on the crud, too:

Carb_Restore_Walnut-13 by clair_davis, on Flickr

The finish is brighter, which I like:

Carb_Restore_Walnut-14 by clair_davis, on Flickr

But the anodized plug took a beating:

Carb_Restore_Walnut-15 by clair_davis, on Flickr

The walnut shells definitely resulted in a nicer finish, and it doesn't really look like they affected the original texture much - if at all - but they are clearly aggressive enough to affect smoother or softer parts like the plug. They also took more work than the Eagle One. A compressor and gun set up to work in that media would have made life nicer, but I have to work with what I've got. Might be able to combine the two for a decent effect, and I might try that later. Have the wood bleach / oxalic acid to try next, hope to get to that this weekend since it's supposed to be below freezing for a couple more days...

Thanks for the suggestions so far,

Clair

Thanks for taking the time to document all your findings here with us...stuff like this is cool.

The last carburetor I rebuilt turned out working great but looked like hell...those gallon jugs of solvent you get to soak them in may as well be water as it did nothing to clean and brighten them up like I remember when I was younger.

I'll remember what works best here and give it a try next go round I have with a carb

So I had a chance to check the oxalic acid option yesterday - nice weather and the kids in their rooms for a while,

Carb_Restore_Oxalic-16 by clair_davis, on Flickr
so I mixed up at test batch of acid consisting of a fat TBSP of the powder in about a cup of hot water.


Carb_Restore_Oxalic-17 by clair_davis, on Flickr


Carb_Restore_Oxalic-18 by clair_davis, on Flickr

Painted it on with a small brush...

Carb_Restore_Oxalic-19 by clair_davis, on Flickr

...and let it sit for 2-3 hours since it didn't start foaming right away like the Eagle1 stuff did...

Carb_Restore_Oxalic-20 by clair_davis, on Flickr

Since it had dried out, I wet it down again and I didn't have a lot of faith that anything had happened. However, once I rinsed it and dried it, I could see that had done something:

Carb_Restore_Oxalic-21 by clair_davis, on Flickr

I added the lines to help define the breaks a little better. The oxalic acid brightened the aluminum much more than the Eagle1 did, but not quite as bright as the walnut shells did. I may do a follow-up test with some oxalic over the Eagle1 to see if it brightens up any, but I may just follow the oxalic acid with a dusting of walnut shells for a little more shine.

That's all I've got for now. We'll see how this turns out in the next week or so if I'm lucky.

Clair