Painting Fibreglass Fuel Tank?

[Tony T]

I've never worked with fibreglass at all, so I need you fellas to bestow your infinite knowledge upon me. 
I need to paint the fibreglass fuel tank on the Ossa, but then wondered if it was prone to vapours leaking through it like plastic tanks?
And is there any special preparation required?
Any words of wisdom most gratefully accepted. 

[Montynut]

I would recommend using a tank sealer as the modern fuels are not very kind to the old fibreglass tanks

[David Lahey]

What Montynut said +the resin in the Explorer tank will not only have compatibility problems with modern petrol, but it is also 35 years old so there will probably be fibres being released and fine cracking of the resin. Lining with a coating like epoxy will seal all the loose strands and cracking and be very resistant to modern petrol.
Be careful when choosing tank sealers because they are not all made for fibreglass tanks.

[Davey Crocket]

My painter is the guru, I can ask, make sure the outer gell coat is not damaged or rubbed through....I would ask a boat place that does fibreglass work.

[firko]

Tony I've painted Maico 'glass tanks with rattle can primer and final colour for years with no drama. I'd most definitely be coating the inside of the tank to prevent ethanol damage however.

[Cabmkr]

    If you can get caswell tank sealer in OZ it works great. I did my IT400 tank and have had no bubbling what so ever and its for fiberglass tanks also.

http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html 

[KTMaico]

External tank prep......

Sand tank 400 grit wet and dry,
Clean after sanding with Prepsol (wax & grease remover)
Spray on Etch Primer. (2 coates)
Spray on suitable primer (2-4 coates)(depending on what colour coating is to be used eg... Acrylic or Polyuethane)
Sand Primer with 400 grit wet and dry sandpaper and make sure you do not rub through the primer.
Tank is now ready for top coat colour

Kevin

[Tony T]

That's terrific, folks.
That answers all my questions.
Thanks!

[Tim754]

and NO ACETONE anywhere near the  tank Tony ,like as a cleaning agent , paint thinner or mixed in fuels.

[Gippslander]

Thanks KT Maico, am doing the old Ktm/Penton tank in the next few weeks, have done the internal reseal and was wounderin' about the paint process, now I know