38 Dgms

[Guest horncock]

my 2 l pinto will only idle with the "low vacum enrichment device " disconected from the small vacum tube at the base of the carb. When connected it squirts fuel from the pump jets continually, what ever the idle speed, the idle is quite smooth at about 850rpm. Am I connecting the small vacum pipes up wrongly? or is there some thing wrong with the carb?

[Big Jim]

If you mean that green (usually) sensor that's found under the manifold, with all the vac pipes etc going to it, then smash it off with an irish screwdriver and fit those pipes as shown, with the main vac pipe going straight from Dizzy to carb.

[Peter Bell]

Sounds like you may need a new diaphragm in the unit. The vacuum at idle should hold the diaphragm against a spring, when the vacuum 'decays' ie. when the throttle is opened, the spring closes the diaphragm and pumps fuel into the carb. So either the diaphragm is leaking or possibly there are airleaks on the inlet manifold.

Peter

[Guest horncock]

every thing seems fine. any other suggestion? I have fitted a stage 2 cam could this be causing a problem?

[Peter Bell]

The cam shouldn't make any difference unless it is miles out of timing. If the engine runs ok without it connected and the vacuum tube blocked then leave it like that and you will get good mpg! but you may find that the pick up from idle is poor. If you are sure the diaphragm is not damaged, check there is not a hole in the tube anywhere causing the diaphragm to flutter and pump continually. You could try increasing the tick over a bit as it might be convinced the engine is going to stall so it pumps fuel in. The extra gubbins under the carb that Jim advised to delicately remove is a temperature sensitive switch so that it only works when the engine is cold.

Peter.

[Big Jim]

Just check where you have the vac pipes connected to. the dizzy is connected to the one on the flange, right next to the rocker cover. the other 2 that are in the phto should be connected to each other.