OzVMX Forum

Clubroom => Tech Talk => Topic started by: mainline on October 29, 2013, 07:30:38 am

Title: fibreglass fuel tank
Post by: mainline on October 29, 2013, 07:30:38 am
With today's fuels is it possible to properly seal and use a fibre glass tank?
Title: Re: fibreglass fuel tank
Post by: bazza on October 29, 2013, 07:52:55 am
I had a skinny works maico fibreglass tank,now donated to firko. Used for 20yrs using our 98 fuel or a mix of 98 and Av gas never had problem
Title: Re: fibreglass fuel tank
Post by: tony27 on October 29, 2013, 08:58:23 am
An old tank would probably need to be lined, the new tanks should be build with the newer alcohol resistant resin.
I've seen this question discussed several times in the UK on trials sites & the fact that there is a new resin for fuel tanks was mentioned a few times, it's not just fiberglass tanks that have issues with the ethanol though as my sherco trials bike's nylon tank grew to the point of not fitting into the frame when 98octane gained 10% ethanol & lots of other people around the world have had the same problem
Title: Re: fibreglass fuel tank
Post by: firko on October 29, 2013, 09:28:53 am
I've lined nearly all of my 'glass tanks (thanks Matcho Mick) after seeing the fibreglass tank on Alan Jones little purple Honda Metisse, Ugly Betty self destruct from the inside out after leaving
 ULP in it overnight. I couldn't believe the damage it caused after only one night, the bottom was almost eaten away and the walls all bubbled out...(it's been replaced with a steel version). The only tank I haven't done is the flame jobbed Trackmaster tank on one of my flat trackers which is fine after using 98 ULP in it at Broadford. I emptied the tank immediately before putting it on the trailer which I'm guessing didn't give it time to start the corrosive process. I will be coating it before I use it again however. If you're talking about the fibreglass American Eagle tank I gave you Paul, do it.....it's a 40+ year old tank that is likely to self destruct the same as Alan's little Rickman job.
Title: Re: fibreglass fuel tank
Post by: asasin on October 29, 2013, 10:08:25 am
I use the fiberglass tank on my cooper it seems to be ok without liner ( alcohol  might be a different story)
Title: Re: fibreglass fuel tank
Post by: mainline on October 29, 2013, 10:45:38 am
I've lined nearly all of my 'glass tanks (thanks Matcho Mick) after seeing the fibreglass tank on Alan Jones little purple Honda Metisse, Ugly Betty self destruct from the inside out after leaving
 ULP in it overnight. I couldn't believe the damage it caused after only one night, the bottom was almost eaten away and the walls all bubbled out...(it's been replaced with a steel version). The only tank I haven't done is the flame jobbed Trackmaster tank on one of my flat trackers which is fine after using 98 ULP in it at Broadford. I emptied the tank immediately before putting it on the trailer which I'm guessing didn't give it time to start the corrosive process. I will be coating it before I use it again however. If you're talking about the fibreglass American Eagle tank I gave you Paul, do it.....it's a 40+ year old tank that is likely to self destruct the same as Alan's little Rickman job.

Yep, I was talking about the American Eagle tank. I put a liner in a plastic YZ tank hoping the stickers would stay on but didn't have any luck. Might have to talk to Matcho Mick. Cheers
Title: Re: fibreglass fuel tank
Post by: David Lahey on October 29, 2013, 12:20:16 pm
I've coated some 1970s Spanish fibreglass tanks internally using epoxy resin and not had any problems despite leaving unleaded 98 petrol in them continuously for years.
The 1970s Spanish fibreglass tanks I haven't coated yet also have had unleaded 98 in them continuously for years, and they have not had any problems either.
My son's modern GasGas trials bike fuel tank seems to have grown a bit in size. I think it is made of HDPE which I would have thought should be very safe with any sort of fuel.
Title: Re: fibreglass fuel tank
Post by: firko on October 29, 2013, 12:55:51 pm
Quote
  Yep, I was talking about the American Eagle tank. I put a liner in a plastic YZ tank hoping the stickers would stay on but didn't have any luck. Might have to talk to Matcho Mick. Cheers
So is the B40 project back on line Paul ;).
Title: Re: fibreglass fuel tank
Post by: bazza on October 29, 2013, 01:17:27 pm
yeah mainline you know you want that beeza going
Title: Re: fibreglass fuel tank
Post by: mainline on October 29, 2013, 10:03:54 pm
Quote
  Yep, I was talking about the American Eagle tank. I put a liner in a plastic YZ tank hoping the stickers would stay on but didn't have any luck. Might have to talk to Matcho Mick. Cheers
So is the B40 project back on line Paul ;).

not entirely sure, life's been pretty hectic so projects have stalled. I'm still keen, just need some spare time (and a little spare cash)
Title: Re: fibreglass fuel tank
Post by: Tim754 on October 30, 2013, 09:01:02 pm
Mr Moto-Tumbi (Matcho-Mick?) perhaps you may have some more insights here?
Title: Re: fibreglass fuel tank
Post by: Zakk on October 30, 2013, 10:07:33 pm
you shouldn't need to seal or line the inner if the fibreglass tank was made correctly, unless you're using methanol?
i made a kevlar/fibreglass fuel tank for my historic roadrace bike and have been using it for nearly 10 years, i used to use leaded race fuel but lately 98 and it's fine. its survived a couple of big crashes with no signs of weakening. aslong as the tank is made using the correct resin and cured then it will be fine.  i'm planing to make one for my IT250J soon too as there are no plastic ones available.