Evening,

I have a Ford Pinto 2.0lt SOHC with Twin Weber 45's. I have a Vacuum hose that runs from the inlet manifold to the rocker cover oil cap (yellow plastic type). When I have been getting the engine setup and running, it is proving to be impossible to get running well with it connected. The only way to get it running well is to disconnect and cap off the hose to the inlet manifold. With it connected it not only runs terribly, it also makes hissing noises front the dip stick making me think there is toommuch negative pressure it's creating. Has anyone else experienced this or got any good ideas?

Regards,

Ashley

Well I guess you've discovered how it should be connected. By connecting it to the filler cap it's effectively an open tube!

My understanding is that you do want some negative pressure to avoid leaks so leaving it disconnected would not be ideal?

From my dim and distant memory the take off on Webbers should be attached to the distributor to give you vac advance on the ignition. The connections need to be stabllised other wise you will be getting modulation in the advance. The connection on the filler cap needs to go to a catch tank unless you are happy with the oil running down the engine.
That's all from my memory so I may be totally wrong, it would account for bad running though.
If you are not connecting it to the dizzy you can just blank them off.

^^ sounds like someone has attempted to setup the twin webbers like you would have done with a single downdraft carb.


On the standard pinto the rocker breather would be connected to the inlet manifold (along with the crankcase/block via the PCV )


but with twin webbers you'd normally run all the breathers to a catch tank instead (pinto's can be quite heavy breathing engines so blocking them off completely is not recommended)



or you can get cheaper versions on amazon/ebay - or make your own


If your dizzy has a vac. advance - it could be connected to the manifold, but as you have 4 inlet runners, you can't just connect it up directly as the dizzy won't like the pulses you'll get from just 1 cylinder

Hi AJ
On my pinto before I sold it
The oil filler cap was completely blocked off
And the oil pvc filter was piped to a oil catch tank with a small filter to atmospheres
The vacuum pipe from the carbs goes to the dizzy or better still a different ignition system
I had a h and h dizzy fitted
Graham
Do some research on hear you will find your answer

On mine i just ran the breather hose into the inner part of the air filter so the fumes would be pulled into the engine to be burnt. There were some valves on the standard engine that allowed you to connect it to the manifold. But all your doing now is creating a huge uncontrolled air leak. Don't block it off as you'll pressurise the engine and blow oil out all the seals.