Hello, I'm trying to rescue a Holley NH carb that has some major rust from gas sitting in it for years and years. The bowl will need to be replaced due to a hole but wondering if the carb body and be media blasted? I can paint the outside but not sure if the inside is treated at all? I'm sure I ca get the rust off but what's going to stop it from returning?
If this is a lost cause does anyone have a favorite shop for a good used or new carb? I looked at Lang's, Mac's and Synder's new carb's running around $275. Thanks for any advice.
David, I would not Media blast the carb body. There is a rust removing solvent that you can soak the carb in over night. It will remove the rust. you can buy the bowl and most of rebuilding parts from Langs.
On the other hand, a Holly NH is a pretty common carb. You should be able to find one very easy.
I wouldn't be too quick to media blast because it is very hard to get everything out when you are done I prefer to use a sonic cleaner with a mild acid for tough corrosion (read white vinegar) it may take longer but the results are good. trying to clean walnut shells /glass / abrasive material out of small passages is a P.I.T.A.
I would blast it then soak in carb cleaner overnight. Then rinse with water, blow with air, and check the passages with carb cleaner spray.
I blast them all. In my experience there is no other way to actually get them clean. I generally don't rebuild NH's but when I do I blast them, drill the passages, resurface the mating surfaces and put them back together. I powder coat the ones I do but a lot of people use paint or just wipe them down with oil and consider it done.
What Stan said. Generally if they are that rusty the passages are more then likely blocked and will need to be cleaned out anyway. Unless you are going to remove the tag, cover it with tape before you blast it. The tape will protect the tag. I just logged in to post but Stan beat me.
I would blast it with glass beads and not paint it. It will be coated with oil and fuel most of the time and will only rust if it sits around outdoors or in a barn for decades.
Thanks for all the advice. I did run the carb in my ultrasonic tank and use a rust remover/gas varnish remover but think I need to soak it another few days.
Here is what the carb started out as:
I know I can replace the bowl this one actually had a hole from the rust. So I will see if soaking and maybe a bit of bead blasting helps if I don't think it's going to work out any fav's for carb suppliers? Thanks!
I will post the after photo next week.
Yours looks about the same as mine except my bowl is fine. I'll be watching this thread with interest.
The carburetor parts all come from the same source. I would buy from either Langs or Chaffins or Bob's. Whichever is closer to you.
I have three Kingston L4 carbs in roughly the same shape. Maybe a little worse. I'll be watching this thread and trying to develop a plan of attack. Looks like quite the fun project you've got there!
You could always braze up the hole. Yeah, I'm CHEAP!
Just to close the loop here, I ended up finding another body during the process of cleaning and trying to get this apart I ended up stripping out the brass main jet and could not get it out so the plan is to remove everything I can to the other body and rebuild.
Blasting is OK for the outside, but to reach the rust that the sand is gong to miss you can give it a bath in Evaporust for a couple of days. When a needle seat refuses to budge, you can turn the body red then let it cool. That usually loosens things right up.