Paint under the petcocks?

[Mashermoto]

Getting closer to finishing this rebuild. I've got the paint job done and consentrating on mounting all the hardware to tanks, fairings, seats, ect.



Here is my question. I masked off the area where the petcock gasket resides, but now I'm second questioning myself. Does anybody recall if that surface area is painted on an OEM tank. Something tells me an original tank is painted across that surface area and the petcock gaskets mount against the painted surface. Either way will probably work, but I have reasons to repaint that area.

[Montreux_Blue]

I've had the petcocks of my Special a couple times, been a while though, and seem to remember it being painted there. And I like the Yamaha stripe.

[petejw]

My spare tank has that area painted,
personally i wouldnt think it would matter to much
if its not painted, but id put some goo between the gasket and
tank.
The bikes looking good also,i like the bottom air scoop.

[Incubus]

I painted that area when I painted my tank. I used automotive clear coat that resists gasoline. The paint still melted and the petcocks leaked around the gaskets. I had to strip the area you've already masked.

I suggest you leave it alone.

Patrick

[TADracer]

Makes no difference unless you have exposed steel showing after you install your petcocks. If you are worried about it, mask off and hit it with a few passes of clear from a detail gun.

[trbig]

What I suggested to a guy yesterday in a PM may work?? Anyone tried using gun blueing? It's a liquid you just rub on steel and it turns it a dark blue/black. It won't make it rust PROOF, but it will help prevent it a lot. It will chemically change the surface of the metal without adding any thickness like a layer of paint. It's cheap... any gun shop will carry it. Even Wally World had it last time I needed some. Maybe a light film of oil over the top when you're done before installing the gasket.

Just a thought.


Tod

[T99Ford]

Don't paint that area. The best seals are done between metal and metal. This is because the paint is always subject to either wear or decomposition. For instance, wheels on new heavy equipment have to be retorqued after about 10 hr of operation, since the paint between the wheel dish and the hub wears, and the hardware gets loose. Or, you could have a problem like Incubus did, and the gas can wreck the finish and you have a leak. Most sealers like silicone do not resist gasoline well either. I would assemble it with dry gaskets, making sure that all your sealing surfaces are clean and free of oil. Then make sure your hardware is tightened to the maximum rated spec. Check it after a little while, since you can get some crush on the gasket, as well.

Nice bike, by the way

I don't know why there is a thumbs down up there, I didn't do it!!

[fredintoon]

Hi Marty,
the factory don't mask that area and their paint stands up just fine.
Your paint may or may not be as gasoline resistant.
I have always painted over that area (more accurately, I have never bothered to mask it off)
and the 2-part automotive paint I used has been OK too.

[Mashermoto]

Wow, the response to this question turned out pretty good

The way I read it we have a hung jury Half say paint and half say don't paint. I went by the House of Kawasaki on my way home from work to talk it over with JC the parts guy. I wanted to know how these tanks came from the factory and the answer is...painted.

I also mentioned in the opening thread that I had reasons to consider repainting this area. See the next picture for the why.



If you look closely you can see the strip of paint I sprayed over. I covered each side with a strip of 2" tape and then cut out the areas for the petcock gaskets, leaving that area masked off and removing the excess tape. During the final buffing, I noticed that I forgot to cut out the petcock gasket area on the right side and left the full strip of tape

So, I have to pull out the spray guns again to do the touch up so the question comes down to how I touch it up. I've decided to paint the whole surface and abandon the idea of masking off the gasket area.

So there...you now know my blunder I think I will sleep better after this is all over

I have lots of photos in the Mashermoto double secret vault to share when this build is complete...but here is a purposely leaked photo

[Elevener]

Your front tire is making faces at me. Nice bike man. Would look good with some clubmans.

[fredintoon]

Gee Marty,
that painted-over tape is now a part of the tank finish.
Just bung the taps back on.

[T99Ford]

I guess I don't know how picky you are, but I don't know that I would leave the tape on. It will peel pretty quick, and then you will have to look at that, even if it is on the bottom.
Given the choice, and since you will be painting it again anyway, I would still mask it off again, and get rid of the rust, too. The paint won't help petcock sealing in anyway, and could likely cause the opposite. Take it from a guy that has to tell 15 others (if it can leak hydraulic oil, engine oil, fuel, coolant, refrigerant, or battery acid, it will)how to seal stuff very day, go direct on metal. The only reason they paint it from the factory is so they don't have to pay someone to mask it. You WILL get a better seal going metal to metal, every time. And since you have the choice, why not?

This is not to say that it won't work the other way, it is just more common assembly practice to not have paint under your gaskets...



Oh, and do get clubmans!!!!!!!