VX Engine cutting out

[Paul Greenway]

Hello All,

I am having problems with my VX HPE cutting out. It starts (from cold) and idles okay for 4-5 minutes then cuts out. If I re start it, it then continually cuts out. Upon driving it cuts out at every junction unless really revv'd highly and then continues to do this for about half an hour until really warm (even after motorway use). Only then does it appear happy and runs smoothly.
Anyone got any ideas as to whats causing this?

Cheers,

Paul Greenway.

[hutch6610]

Hmm .... another carb fault.

Volumex's can cut out at idle due to three main causes - short of somebody messing with the idle/mixture settings.
I will list them below for anybody with a VX then tell you how to get around your running problem

1. Blocked jets - that's the tick over ones either side of the carb.
2. Full load diaphragm has become perforated - this causes the car to run so rich at tick over that it stalls all the time and runs lumpy, accompanied by black smoke coming out the exhaust.
A sure sign of this is when you can turn the mixture screws all the way in until seated and the car still runs which should be impossible!
3. Mixture/idle screw being set up incorrectly - that's too low an idle or mixture is too lean.

Onto your car.
It car runs correct (and drives properly) until it comes off choke/fast idle.
Now if it was running correctly before and suddenly developed this fault + you have not attempted to alter anything, its your tick over jets.

Two are located either side of the carb - easiest to see is the one viewed from the battery side of the car.
Look at the carb from this side and you will see a slotted brass cap about 9mm or so in diameter, its just below the air cleaner adapter casting.
The other one is not so easy, its on the opposite side tucked under the casting of the carb cover behind the throttle lever.

Unscrew the easy one first, make sure the black "o" ring comes out with it (they sometimes unscrew and are left behind in the carb) and lock for an obstruction in the end of the jet - you will be surprised how a grain of "something" or a piece of gasket paper finds its way in.

Blow it out with air or your mouth - whichever you prefer.
Pop it back in and just seat it with the screwdriver.
Now the other one you will have to be really careful with - drop it and chances are it will never see the light of day again = your not going anywhere!

Best way to remove it is to wedge the throttle pedal down to get easier access, then unscrew it and carefully pull it out with long nosed pliers.

Clean it as per the other one - look at it visually to make sure and again pop it back in just seating it.

Next unwedge the pedal, start the car allow to idle, then open the throttle and keep it revving around 3000rpm is just fine, undo the screw cap of the jet about half a turn and screw it back in - do the same on the other side.
This as mentioned else where is to flush anything that may be floating around in the gallery so it does not get into the jets again.

In theory it should now run - famous last words - and you can tighten them both up properly.

Drive the car and repeat the revving and unscrewing of the jet if you have too.

See how this goes and let us know how you get on.

[hutch6610]

Odd you should say that - read the following.
http://www.betaboyz.myzen.co.uk/forum/index.php?topic=348.0
This usually happens after a long layup.

Try it and see how you get on, post back if you have no joy..

[Paul Greenway]

Thanks Hutch,

Took your advice with option three and Hey Presto it works. Car seems to idle fine and did not cut out once on a 20 mile spin. Next issue is finding out where it is blowing from- somehere around the manifold.

Thanks once again,

Cheers,

Paul Greenway.