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Old 09-08-2014 | 04:39 AM
  #2246  
vandalzzz's Avatar
vandalzzz
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Joined: Jul 2013
Posts: 762
From: somewhere near Japan
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Originally Posted by vandalzzz
So, here is another one sort of bug report.
Issue: new (revised) tank can be cracked causing pressure problems and therefore tuning issues. Crack is so small and located in unobvious place making pressure test close to impossible.
How to repeat: side impact slightly above pipe line where most stress is taken by the outer rear fuel line clip.
Result: screw holding clip causes crack of the tank body starting from the screw' hole.
Major issue is about unstable nature of this damage: with body off and clip aligned well there is vrtually no pressure leak. With body on it applies some force to the clip, and not so soft landings temporary increases this force. While buggy is being upside down force is high enought to remove all pressure from the system and cause flameout.
But when you take tank off and decide to make leak test, you remove clips and screws also. or at least don't apply force to that rear outer clip, therefore silly drivers with weak lungs don't have a chance to detect this leak.
Workaround: mount this clip facing rear left wheel or/and apply some material betwwen tank sidewall and clip.
Hope this will help.
Spent some time to investigate a bit more, and here are two pics.
First. Fuel clip is mounted as per manual:

Its obvious that body can transmit impact force thru itself to that clip i.e. during upside down landing on the pipe, causing cracks like i've.
Second pic. Fuel clip facing rear wheel:

Even during hard crashes clip doesn't act as support for body, so no stress goin' to tank in such configuration.
Body is stock, and i have no idea how it looks with FTW body.
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