have fun getting those stupid spacers back in place?




water in pipe = water in fuel = water in car = no go (well once the water built up, but also can cause corrosion in carb, well at least what ive seen in my days, someone will probably say differently )



citroen decided it was good enough to have a push fit onto all the fuel lines, i remember the fuel line from the pump to carb on mine was the first place i realised this, and it slipped off so easily!!
so replaced hose and jubiliee clips are the way forward,
so no not suprising no jubilee clips,
did you replace that peice of pipe? often they go, so even if it hasnt, whilst the tank is out you "might as well" type thing,

and whilst you have dome hose and clamps out, do the chassis leg to pump and carb to pump and jubillee them all up, if not already done.

enjoy

Keith,
that will be the original piece of rubber hose and sometimes it's got the year of manufacture on it, depending where it was cut from the roll.
No hose clips there or elsewhere in the system ex works , as it's 5.5mm bore onto 6mm stubs or nylon pipe.
It's surprising that it was still in usable condition, as most of them have split or crazed by now...


That built in reserve of about a gallon is handy, but best not to abuse it, unless you know how far it is to the next filling station.

One more thing to try, as I'm running out of ideas with this carburettor; while driving along at the speed where the hesitation is most pronounced, gradually pull the choke on and see if this has any effect on the running.
If it does improve, that would be an indication of a weak mixture.
The difficulty is in figuring out why that's still happening, as you've already replaced the original 102.5 jet with a 107.5.

ken

Thanks I will

Keith,
a few more ideas have surfaced...
The secondary main jet is definitely 87.5 or 90?

Also, did you remove the air corrector jets?
One has the emulsion tube attached to it, the other emulsion tube stays in the carburettor body, but it can be pulled out with an extractor rigged up from a bolt, nut and some washers.
Once it's been checked, it's tapped back in using the bolt as a drift.

ken

New ideas welcome ken thanks

I've been called upon for domestic duties today so it'll be during the week before I can delve further.

wow this is turning in to a "mega thread" and thios post isnt going to help

I have similar problems to Bugster and Viking- coming on to 2nd throttle or at fixed throttle there is a surging- as ive gone through the carb re jetted it, but not to the extremes of the company that advised Viking, im going to turn my attention to the nylon pipe , at some point its probably been kinked and weakened and this may restrict flow, also with some of the faffing about a may not have the pipe run just right over the tank saddle area another favourite for kinks

if alls well there ill get back into the carb and make sure that nothing has dislodged from the fuel line during the return from France that may have affected any of the drillings or jets ill double check 2nd butterfly is closing and opening when its supposed to. Doubtfull its bits in the line as it was new rubber but nylon and fuel pump were of un known provenance and at the back of the lockup for a long time, as was the carb-it was swapped over not because I didnt know how to jet it but because the idle jet needle had corroded and ruined the threads

nothing serious just that slight hesitation/ surging fixed throttle at 60mph- (suppose it could be the diy iggy module now i think about it )

Sean

I have the luxury of several parts and carburettors in stock but not the luxury of fatting around with carburettors not behaving. The time factor is important, I can’t charge customers using too much time finding the problem unless the ‘’normal’’ faulty parts are replaced and problem gone. When problems persist more drastic measures are needed time wise too. I fitted a reconditioned carburettor (standard set up) the hesitation vanished and is still running well today 2 weeks later.
1 carburettor may work on 1 particular engine but not on another. Weird you may say, maybe not. The carburettor is not a complicated device just delivering right mixture for burning and here I think the problem is. Our old engines despite acceptable compression which seems to be the indicator for how healthy it is, may struggle at higher revs forming correct vacuum, filling the cylinders correctly and burning the mixture at the right moment and in the right manner. We have little tools if any to measure this. A simple compression test at crank over will not reveal this. Also the oil breather is loosing its vacuum at high speed, creating a pressure which can also contribute to incorrect mixture being delivered to the cylinders.
I think we can forget about fuel delivery from the tank to carburettor + all items on the electric side as potential problems.
No point redoing the job again and again. If possible maybe borrow another carburettor, it takes 5 min to fit and go test driving. Yes it sounds crazy but you either confirm or eliminate the carburettor. Most carburettors are 20+ years old and they do need replacement as they too get worn out.

Hmm,makes sense I suppose.

Well I'm delighted to say the problem is solved with the help of some useful tips from ken, thanks

Having removed the tank and replaced that small rubber pipe from sender unit to nylon fuel line and removed and cleaned the petrol pump the top speed of the car went from 62mph to 72 on a slight down slope and 65 on the return trip back up. So I presume that before there had been an air leak which was reducing the amount of fuel delivered to the carb.

The hesitation/flat spots improved slightly but didn't completely go away. So back to the carb and at tickover a trickle of oil was dribbled into the secondary butterfly which caused the engine revs to drop and nearly stall. So the secondary butterfly wasn't closing completely and was adjusted out one full turn of the screw to allow it to close. When oil was again dribbled in there was no change in revs so it had now definitely closed. A road test showed much smoother running and the hesitation was less noticeable.

This was with a 107 main jet, so as I had a spare 102 and nothing to lose, I drilled it out to c.110 and fitted it.

Bingo, hesitation gone and the car just purrs along now. Smooth transition from coasting throttle to acceleration without a trace of flat spots and acceleration is instant from low or high revs. There's also much more "grunt" now from low revs and it pulls like a train from 30 in top, hill climbing is stronger too. The transformation is amazing - I didn't realise how poor it had been before.

I think the 110 jet is actually only recommended for the Ami engine but it certainly works just fine in mine. Perhaps it thinks it's an Ami

Once again my grateful thanks to ken for his help - couldn't have done it without him .