Cabrio carb

[Mickaleen]

Re: Cabrio carb

Hi liz,
The timing is controlled by the ecu being electronic, no manual adjustment is possible.

[greyV8pete]

Re: Cabrio carb

Hi liz,
The timing is controlled by the ecu being electronic, no manual adjustment is possible.

Crank position sensor?

[greyV8pete]

Re: Cabrio carb

I fitted a Facet fuel pump to supply a retro fitted 34ich Weber carb on my old classic.


https://www.merlinmotorsport.co.uk/p...-psi-fac-ss500
Note with these you must use a pre filter or the guarantee is invalidated!


https://www.merlinmotorsport.co.uk/p...mm-fac-ss-filt


Or there is this one at slightly higher pressure


https://www.merlinmotorsport.co.uk/p...-psi-fac-ss501


and as belt and braces i fitted a simple fuel pressure regulator set at 3psi according to the adjusting knob, it does not have a built in pressure gauge.


https://www.carbuilder.com/uk/pro-fl...6mm-hose-tails


When checking the throttle spindle for play, first remove the rose tinted spectacles. A very very small amount of play only up and down may just be ok but to get any chance of setting the carb up there should be none! If it rattles then bin it! Peter.

[dogoncrazy]

Re: Cabrio carb

I've looked at a couple of images that both show a crankcase ventilation pipe running round the back of the engine to the manifold , so somewhat confused that you say your engine is minus this pipe. Also that's it's a known problem within the Sierra owners with that engine that it's prone to breaking down and causing unstable idle.

[Mickaleen]

Re: Cabrio carb

Hi,
The crankshaft ventilation is via the top of the camshaft cover in the form of a 90 degree elbow which is connected to the air cleaner. There is another ventilation pipe exiting the block under the inlet manifold which connects to the inlet manifold. There is no pipe going around the back of the engine.
Thank you both for your input, I have already ordered an after market fuel pump.

[Mickaleen]

Re: Cabrio carb

Hi Peter,
Many thanks for the links much appreciated. New fuel pump should be with me either Friday or Monday.

[Mickaleen]

Re: Cabrio carb

Hi,
Have received and fitted the new electric fuel pump. The in-line filter is now filling up however, the tick over remains unchanged.
The only coarse of action is to replace the carburetor. Every other avanue has been checked and failed.

[jon_cox]

Re: Cabrio carb

Hi,
Just before you throw in the towel.........
I read you have replaced the spark plugs. What about the HT leads, all of them, including the coil lead. Leads can break down over time and can cause hunting.
I know it has been said in a previous post but....... Please double check that the automatic choke is definitely working correctly and completely opening properly.
Then wind back the throttle position screw so that it is no longer in contact with the throttle cam. Now check that the butterfly fully closes correctly. There should be no light / air gaps. This will now only expose the idle circuit. Start the car. If it does not start / tick over then the idle circuit is blocked. Check the idle mixture screw, this should now have an effect. It seems counterintuitive to have both the butterflies fully closed but this is how the weber carbs are designed. The idle circuit should take over the fuelling.
Also, the idle circuit draws in air through a small jet which controls the fuel air mixture, this in turn exits via a small hole at the top of the carb into the air filter. Make sure this is not covered by a badly manufactured air filter gasket or incorrect air filter base plate for the carb.

[dogoncrazy]

Re: Cabrio carb

I was just about to post, but Jon has beaten me to it for the most part.
Unless there is significant wear in the throttle spindle /and or the spindle housing then why would you replace the carb? There is nothing else that 'wears out' I still think the problem is with the idle circuit, as it seems does Jon.

[Mickaleen]

Re: Cabrio carb

Hi,
John, the ignition has been gone through and is fine.
There is no Automatic choke that was removed many years ago.
The idle circuit may well be blocked although all appropriate steps were taken without success.
The idle mixture screw has no effect.
All that has been suggested has been done.
It has been suggested that a sonic clean be tried, unfortunately there is no one able to carry out that locally.
I have done all I can and carried out all suggestions for which I am very grateful to the community for.
A new carburetor to be put on order.

[Mickaleen]

Re: Cabrio carb

Hi,
Just an update on my problem carburettor, New one received yesterday and fitted. All is well, problem gone.
Emissions to be set bit awkward at the moment due to the coronavirus with garages closed.
Thanks to all for your time and assistance.

[greyV8pete]

Re: Cabrio carb

Good news. At least you can enjoy optimal performance from that part from now on. Presumably the new carb came with setting up instructions? If not have a look at the link below. If the carb was original fitment for that engine, and the engine is unmodified, then its unlikely that you would need to get into jet changing. However the left hand column should give you a good indication of basic settings to get you up and running. Emissions can wait until later. Peter.
https://www.carburetion.com/Weber/adjust.htm

[dogoncrazy]

Re: Cabrio carb

Glad you have the problem sorted but a shame that we'll not know the root cause.

[Mike Cole]

Re: Cabrio carb

Hi dogoncrazy,
I believe the problem was in the idle circuit, which you hinted on earlier in this thread. Without delving into the carburettor and drilling holes into it, it's more than likely to have been the cause.
Thank you for your input.
Kind regards
Mike.

[Mike Cole]

Re: Cabrio carb

Hi Peter,
I have the setup instructions that came with the new carburettor which is original fitment. The carburettor is a direct replacement for my Ford Sierra engine, bought from Webcon.
Thank you for the link and for your input.
Kind regards
Mike.