After finding my twin carbs are leaking more than ever after engine switched off for a while, I have decided to get a local engineering company to check the spindle bushes. I did replace a lot of the seals a while ago but was not brave enough to change the spindle ones - probably the cause. They did say the bushes did not seem too bad. I did check the jets when all apart and found the following: Main 135 Idle 60 Pump exhaust/spill 40 Emulsion F78 Air corrector 160 It ran quite well, but as others have said, getting the F6 emulsions should improve everything. Will get it all back together soon and am hoping for a decent power increase when Bob the tuning bloke comes to visit with his van of tricks. This will be the first time tuned properly with a Buttys Bits pedal kit now giving me full throttle too. Fingers crossed.
Im certain we have F6's in our ICT's along with F78 emulsions too, I think our mains might be 155's though (1641). Let us know how the Butty's linkage goes on will you please, Im toying with the idea of fitting one!
Mine is 1641. The Butty's Bits kit is already fitted and took around half an hour. Easy to do. What a difference it makes! Not only full throttle but better return, no slack and feels more like a modern car (or bus!). The accelerator is more sensitive to small movements so you can speed up smoother with more control. These kits are so worth it.
Dohhhh bloody iPad, we don't have F6 and F78 at all, we changed them from F78 - I really do need to wear my glasses now a days, can't see the screen properly! Thanks for the feedback Skutterbob - I might just visit Buttys website later!!
Hi. Could you please post a pic of the Butty's linkage. I bought one but cant seem to get it to fit well. I end up with an overly steep pedal.
mine has the 72 to 74 linkage. is on some early and late bays. it has a rod across the floor. F6 emulsions on my 1641. definitely better.
Spindles may leak but the petrol has to be pouring through the carb for this to happen so either you have too much fuel pressure or a faulty float valve. ICT's can't cope with the pressure from a std mech pump so it needs reducing. F7/8 over-fuel when you try and accelerate - too many 'oles. After these basics, maybe try some smaller idles. 55's if it's still rough at lower revs.
I do have a regulator at 1 psi. No leak when running, just a dribble when stopped and not all the time.
Is it an empi one? Shiney chrome? I suspect these might be in BAR not PSi because even turned right down my Dells still flooded. I replaced it with a filter-king regulator, but you need an accurate pressure gauge to set those up. It's likely that they are also available at fixed PSI, I didn't check as I had one kicking about.
ALL my recent carb problems were down to over-fuelling one way or another so I have a bee in my bonnet at the moment. Could be something else entirely.
Set your ICT fuel pressure to 2.5 psi. That should be fine. They don't like anything over 3psi. 1 Bar is 14 psi. (sorry if you already know that.) My stock fuel pump was pushing out up to 6 psi and giving me overfuelling problems. fitted a rotary eleccy pump now.
Anything above 1.5psi and they leaked a bit on stop. I will see if the engineers reckon that the spindle bushes need replacing.
Mine is a Facet Sytec - the shiney one with the twist top. It is in psi and can adjust from half to 5.
No idea, they came with the bus. I bought rebuild kits from Eurocarb and changed everything except the spindle seals. There is a bit of movement from the spindles but the engineers thought it was not too bad. They still have them - got to remember to call them on Monday. Will change spindle seals when I get them back.
Even with perfect spindle bushes it will leak fuel from them if the float height isnt set properly,the float has a hole in it,theres debri in the needle of the float valve or the fuel pressure is too high and overriding the float valve