Has anyone succeeded in replacing the diaphram in the center carburetter without first dismounting the entire center unit? I'm sure it's probably wishful thinking but it doesn't hurt to ask. Mine is leaking fuel badly and cannot be run until this repair is made. Tom

Submitted by tvtom@sbcglobal.net on Sat, 09/29/2012 - 11:12

Don--- I finally did cure the fuel seepage problem by continuing to tighten the banjo bolts a little each day as the new washers compressed. Thanks for the comments.

Submitted by tvtom@sbcglobal.net on Thu, 09/06/2012 - 20:44

Thanks, Don. I'll give that a try. I did save all the old washers. I have a 13/16 th box-end that fits very snug. I also have a 13/16TH socket which does not fit --- looks like a different number of points.

Submitted by hilstonsmg@aol.com on Thu, 09/06/2012 - 19:58

Tom; I've had the same seepage problem several times on SU carbs and this fix works for me. Where it's seeping take out the new fibre washers and put in the old ones. I think the old washers are somewhat saturated with gas residue and make a better seal. Don't know why for sure, but this fix has worked for me on many Brit cars. As for how tight, I don't think there is a torque value for this and the best I can say is " pretty tight " . Use a box end not an open end or cresent wrench. If this dosn't work try a very thin coat of Gas Tight wiped on the washers, although this will make taking the fixture apart the next time a bit harder. Try the old washers first or just try tighting the banjo bolt a bit more, I've never broken or striped one and they will take a lot of torque, hope this helps. Kind of fun isn't it. Cheers.............Don

Submitted by tvtom@sbcglobal.net on Thu, 09/06/2012 - 18:14

I have completed the installation of all three new diaphrams and am now re-assembling the system. I installed all six new gaskets / washers on the fuel line banjo connections but, after tightening each about three times, I'm still experiencing some fuel seepage. My question is--- does anyone know what the specified torque is?
Thanks,

Submitted by hilstonsmg@aol.com on Thu, 08/02/2012 - 13:15

Tom: Had the same deal on my 66' and was able to do it without much drama, although the use of headless screws to line up parts is new to me and would make the job much easyer. Thanks for the tip Bob. You will be taking off the air cleaner to help get at parts, it only takes a few moments, and a lot of things are exposed that you may want to clean or repaint. Try to get kits for all three carbs as the front and rear carbs will also need attention in the near future and get the new type plastic non sink floats. Do them one at a time and its no more that a days job. It will be clean and worry free for a while at least, It' a great feeling and the club has great books to guide you ..................Don

Submitted by NC19-03320J on Thu, 08/02/2012 - 12:31

Yes, I did it a few years ago and I'll dig around and see if I still have the photos I used in an article about this for our newsletter,. Basically I took one of the bottom screws to the hardware store to try and match the threads which resulted in buying several screws that were not exact but close enough to screw in the carb body a couple of turns by hand. When I was ready to assemble the parts I put these screws in, slid the parts into place and removed them one at a time and replaced them with the proper screws.
Bob