Author Topic: Trouble with fuel tank paint around filler  (Read 4661 times)

Offline the-chauffeur

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Trouble with fuel tank paint around filler
« on: March 16, 2010, 10:02:44 PM »

Guys

OK - my tank and side panels have come back from the sprayers, but having put fuel into the tank to start the bike up, the paint around the neck opening has started to soften and crinkle (I've had this happen before on another bike). 

How do you folks who've painted things prevent this from happening - and is there anything I can do about it now?  Alternatively, is there something I can put round the neck (like a large black rubber band or piece of bicycle inner tube) to disguise the effects of the fuel on the paint/lacquer?

Thanks

Neil

Offline UK Pete

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Re: Trouble with fuel tank paint around filler
« Reply #1 on: March 17, 2010, 07:42:57 AM »
Neil what i did on my gpz 550 tank i sprayed was to sand back the paint to bear metal around the sealing part of filler neck or trim it back with sharp knife if all soft , then spray a load of petrol resistant laquer in the lid of the paint can, and with a modelers brush paint the bare metal and the surrounding tank paint that was not seen under filler cap, or you could mask the area off and just do the prep and spray the area, Btw Halfords sell the petrol resistant laquer.
Pete

Offline PMK

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Re: Trouble with fuel tank paint around filler
« Reply #2 on: March 17, 2010, 08:43:13 AM »
Sounds like non petrol proof laquer was used.

Did you pay someone to do it? if so I'd give it back and say sort it!!

If was a mate then I'd do what UK Pete suggested.

Make sure that you mask the good paint properly as some laquers don't mix and cause real problems finish wise.

Hope that helps
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Offline honda-san

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Re: Trouble with fuel tank paint around filler
« Reply #3 on: April 02, 2010, 08:01:21 PM »

I have found that two things are important here-

The paint should be trimmed back at the filler neck so that the seal is against bare metal rather than on top of the paint. Otherwise the petrol over time seems to work its way under the paint and down the outside, softening the paint as has happened (and Honda did not paint onto the sealing surface either)

And of course petrol proof laquer must be used - Surely ANY painter worth a damn knows that!!!

Cheers - Chris R.
Chris R.

Offline the-chauffeur

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Re: Trouble with fuel tank paint around filler
« Reply #4 on: April 03, 2010, 12:22:32 AM »

Folks, sounds like you were pretty much right all round.

Both of the painters I've used in the past a) painted far too high up the neck and b) didn't use petrol resistant lacquer.  No, don't tell me - I know, I know.  Never again.

Fortunately, I've saved the paint on the neck of the 750 by following your advice.  Cut it down, masked up and oversprayed with petrol reisistant - and it's now fine.  The neck of the CB450 is a different matter; it was too far gone to save.  So I stripped it back to where it meets with the tank, masked up and etch primed, flatted and oversprayed with a very close match mix (the original was a candy, but as well as cocking up the neck, the sprayer put too many coats on and the colour is nowhere near what it should be - again, please don't go there).  Finished with petrol resistant, and whilst not perfect, you'll only notice the colour difference if you really know what you're looking for.

I gotta find me a good sprayer.  Or maybe do it myself next time.

Thanks again.
 

Offline UK Pete

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Re: Trouble with fuel tank paint around filler
« Reply #5 on: April 03, 2010, 10:36:12 AM »
Ashimoto, has  the name of a good painter who sprayed his Bike bits Ruby red, the guy also found a modern auto paint that matches extemely close to the original Honda candy, i will probably get in touch with the guy to find out about what paint he used and get some myself, as i intend to spray up a spare bodywork set for mine one day
Pete

Offline Sprunghub

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Re: Trouble with fuel tank paint around filler
« Reply #6 on: April 03, 2010, 11:34:54 AM »
RS paints do a non-hazardous 2K rattle can of clear lacquer, which is, in my experience petrol 'proof' as opposed to resistant.  It isn't cheap......but it's very handy.  I don't understand the 'science' behind a 2-pack paint being in a can & not "going-off" but it doesn't.   

In my experience it is 'many' times better than the 'High Street' petrol-resistant lacquer, which I have found to be very 'thick' in application & not to actually do what it says on the 'can'.

The RS lacquer is not however, resistant to the blown-back 'mist' from a leaking front brake piston seal  :-[

No need to ask how I know ::)   
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Offline honda-san

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Re: Trouble with fuel tank paint around filler
« Reply #7 on: April 03, 2010, 09:18:12 PM »
Use Dot 5 silicon brake fluid, it does not attack paintwork - pricey at approx.
Chris R.

 

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