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Old 12-06-2012, 06:45 PM   #14
Beastly Adventurer
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Joined: Nov 2005
Location: the west
Oddometer: 1,975
The black nylon fuel distributor lines on these are getting brittle and can develop pin holes.. UV can accelerate decay. Everyone would be wise to check. The nylon tube is available cheap. If the mc is split then replace the lines or complete distributor. Several inmates like Hasenwerk have ditched the oem distributor in favor of aftermarket frame mounted regulator. That also gets rid of the super-crap plastic injector cap which can sheer clean off (see Steverino injector feed repair). At a minimum new SAE J30R9rubber lines ($1ft) should go on every 3-4 years (apparently done by op). Bad advice on "repairing" leaks is to "add another hose clamp".

As noted by Mr Head, the seal occurs over the raised annular bump by the natural elasticity of the fuel line not by the pressure of the clamp which is there only to prevent the hose from popping off. As rubber lines age, they harden and the seal is lost. Early signs of trouble can be discolored telelever from drip at tank barb (can also be from pump plate electrical bulkhead seal gone bad).

One reason pp use QD's is because of how difficult it is to remove the rubber line from the the move-able nylon distributor spider. Use of an external fuel filter gives a solid junction to pull from at least on the high pressure line. The hp out from the filter to the spider need not be disturbed during tank removal because the filter output to spider inlet stays put. That just leaves the return line, so you can easily get by with one less QD or use a straight mild barb where the return QD would go.

With all that said, many collective millions of miles have been ridden on neglected fuel lines w/o incident. It seems that over-heated cat resulting from engine running on one cylinder plus idling on the stand are co-factors for fire. Shut down the engine unless your moving.
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