Powdercoating carburetors.....

[tkent02]

Did one CV carb, a BS32, it was a junker carb just to see how the powdercoating worked. Took it out of the oven, the throttle is stuck. Oiled it, worked it, it moved a little, played with it a couple days, now it moves freely enough that the spring can shut the throttle... not as free as the other carbs, and it's not real smooth. I'm thinking I cooked the throttle shaft bearing. Is it a nylon bushing in there? Bronze bushing? Maybe I cooked the grease in the bushing?? Don't really want to take the throttle shafts out to do this. Maybe powder coating isn't a good idea. I wanted to do it because it looks great and will withstand The Dip, but not if it ruins the carburetor.

Thoughts?

[SVSooke]

The thought of messing up the seals/bearings on the 82 GPz750 carbs is why I did them in VHT caliper paint.Figured the 200 F wouldn't hurt the seals but the 400 probably would.Looks like I was right.

[Who Dat?]

Although I like the usual results of powder coating, I am not intimately familiar with the process, except that I know it involves a LOT of heat. For that reason, I have stuck with VHT caliper paint, too.

Hope we can come to a solution for this, as it would be a nice touch to have long-lasting color on the carbs.

[Nessism]

There are rubber seals on the ends of the throttle shafts. Maybe they melted?

I removed the throttle shafts on some Keihin carbs for a Kawasaki and it was surprisingly easy. Interestingly, they don't have any throttle shaft seals, but pretty sure Mikuni CV's do.

[londonboards]

Getting the butterflies out is what I did, as I had my carbs vapour blasted. I was glad I did it because I found one of the throttle shaft seals was missing from manufacture. Might have caused a little air ingress - who knows.

However getting the throttles out is not that difficult and I just wanted to do it to be thorough.

See my blog post: Butterfly Capers

Here are some pics:











Vapour blasting did this:





There used to be a guy on this forum who did amazing carb work. He was called Renobruce or something and he did stuff like this:



The following thread used to be top notch but now most of the picture links have died (why do people use Photobucket? Google is for ever) but it's still worth a visit:

http://www.thegsresources.com/_forum...022#post999022

So I would say try powder coat (they can get it quite thin these days) but take the throttles out.

Greetings

[tkent02]

Taking the butterflies out seems a bit ambitious for this project. Maybe later but I want to get this thing running sometime this year. The staked screws scare me just a little bit

Were you able to find the right size seals to put them back together?

They look nice with the float bowls and top caps done in Satin Black. Was thinking maybe red bodies for a bit of a hot rod look.
There are low cure powders, some cure at 325 F. I did the last ones at 375 for 20 minutes or so. Maybe 325 won't cook the seals in there. Could also try a little cooler for a little longer and see if that does it.

Good thing I have quite a few dead carbs to practice on.

[londonboards]

Seals still available from Suzuki - no problem. Staked screws are no problem as long as you are braced from behind. I bought new screws to replace them as well. Bit of thread lock and a tap with a punch and you should be good.

[tkent02]

Removing them didn't jack up the threads in the throttle shaft?

[londonboards]

Throttle shafts are stainless steel. Strong and durable. But I would buy new screws:

[60ratrod]

I replaced the throttle shaft seals on my kz's bs34ss carbs and what I did was I ground off the bulged part of the screw. once I did that, the screws came out fairly easily and replaced them with allen head counter sunk screws and red loctited them in. it took a lot of heat to get those screws out with the red Loctite when I went back in to replace even more seals. the bushings should be bronze as the ones in my 34ss were, but who knows.