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SU carb fuel leak


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yes Triumphs leak oil  SU leak fuel    tis said i have an avid hate of the things but now have two on my Mk2 2000  Pah.


I suggest you remove the air piston and look at the top of the jet the fuel should be about 4 mm below the top of the jet 

if its bubbling out the top and then runs down the sides of the jet as there is no seal between the jet and its holder then there's a fuel level problem in the float chamber.  overfilling due to debris in valve ot seating failed , 


having been round in circles with a whole selection of float valves on the 2000 including viton tipped  from a ford packet , Grose jets now are hopless,

I picked up a pair of latest SU offering viton tipped  and two new floats yes they worked ...why...


on examinationof the float there was some wear of the valve pin indented into the float contact face , this is enough pitch the needle and jam it from sealing cleanly


putting the old valves back in with the new floats reverted to working fine, so the culprit was the float not the valve 


there stay up floats about but not for HS4s


if your float has the metal top pivot bridge you wont get this , just the all plastic versions 


hope thats not too much ramble  



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and if you fettle the striker face of the float you upset the float height and need a silly size washer ,very thin  under the valve to correct it 


some gentle work with some wet and dry may work its not very workable plastic, nothing made much inroads and revert to the dremel disc just made a ,

melted mess...I should stick to leggo !!!!  hence new floats from the piggy bank 



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