Author Topic: Painting around the petrol cap.  (Read 1479 times)

Offline MrDavo

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Painting around the petrol cap.
« on: July 04, 2017, 10:44:59 AM »
When my tank was painted last (its not original paint after all, according to Trigger), the top face of the filler, where it meets the rubber cap seal wasn't painted, it's bare metal.

At Crich, I was showing Graham how petrol has got behind the paint around the filler neck and made it very soft / falling to bits. It won't have helped that when I got the bike, the seal was completely perished with age, along with everything else rubber on the bike (I've changed it since). Luckily it only affects the vertical part of the filler neck and the petrol has never tried to spread accross the tank under the paint.

My question is, when I get the tank repainted in the winter, am I right in thinking the filler neck should all be painted and laquered, ie including the horizontal surface that is in contact with the rubber seal?

I don't want to cock it up before I've even started.  8)

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Offline AshimotoK0

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Re: Painting around the petrol cap.
« Reply #1 on: July 04, 2017, 11:15:53 AM »
Andrew Parnaby who painted some of my tanks insists on not painting the area in contact with the seal as petrol causes it to wrinkle and then petrol capilliarates under the paint and causes lifting/blistering etc and gradually creeps downward. I had an excellent job done by Menno on my 500K0 tank and I seem to think he didn't paint the area in contact with the seal either but I would have to check. Menno or James will tell you anyway.
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Offline MrDavo

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Re: Painting around the petrol cap.
« Reply #2 on: July 04, 2017, 12:02:39 PM »
Thanks for that info, Ash, it sounds like mine was done right but ruined by the failure of the rubber seal, as fuel fair sloshed out when I first got the bike, especially if you put it on the side stand with a full tank!

Looking at Yamiya body kit photos they seem to be in primer or bare for that surface, hard to tell if its bare metal or not.



Quote
capilliarates

That has to be word of the day, I checked and it does exist! :)
1969 Honda CL450 'Scrambler'
1974 Kawasaki Z1A
2005 Harley XL1200R Sportster
1985 Porsche 911 3.2 Carrera Sport
1978 VW Bay Window camper van

Offline AshimotoK0

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Re: Painting around the petrol cap.
« Reply #3 on: July 04, 2017, 12:10:45 PM »
Mine from Andrew was bare metal in that area ..in fact that tank is the same colour as mine ! Pretty sure Menno's are like that as well.
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline paul G

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Re: Painting around the petrol cap.
« Reply #4 on: July 04, 2017, 12:16:26 PM »
Bare metal or you will end up with the paint blistering all the way down the neck.
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Offline Nurse Julie

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Re: Painting around the petrol cap.
« Reply #5 on: July 04, 2017, 12:54:47 PM »
I have freshly painted sets here by Menno and it"s bare metal in that area.
« Last Edit: July 04, 2017, 01:57:14 PM by Nurse Julie »
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Offline ka-ja

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Re: Painting around the petrol cap.
« Reply #6 on: July 04, 2017, 04:32:35 PM »
Thanks for that info, Ash, it sounds like mine was done right but ruined by the failure of the rubber seal, as fuel fair sloshed out when I first got the bike, especially if you put it on the side stand with a full tank!

Don't forget the cap has a vent, too much fuel on prop stand and it will find its way out of the vent.







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Offline Green1

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Re: Painting around the petrol cap.
« Reply #7 on: July 04, 2017, 06:17:53 PM »
All mine are bare weather they have been repainted or still original.

Iv not experienced the cap venting on the 550 as it drinks fuel at an alarming rate.
The 750 on the other hand has spat fuel out a couple of times.
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Offline Menno

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Re: Painting around the petrol cap.
« Reply #8 on: July 04, 2017, 10:33:42 PM »
As said before; it should be bare metal.

The rubber seal closes the tank on the bare metal.

It is highly recommended to check the rubber seal in the lid and if it is cracked replace it.
It is well worth the money.


 

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