zx td fuel system connector

8304 · Unread post by **8304** » 28 Jan 2006, 16:56

hello

I noticed on many td engines a fuel connector under the bonnet which is black with 4 inputs / outputs on it. It goes in the fuel line on the return to the pump from the drain off pipes (bosch system) and between the fuel filter and the supply into the pump. I tried putting one on my zx but the car would not runn throwing out white smoke and dying after being revved to 2000rpm. When i start the car in the morning first thing it behaves in a similar fashion but is fine 1/4 mile later... - fitting this unit seemed to make the car show the symptoms i get on first start in the morning but to a greater extent.
What does this black cylindrical unit do - it seems to mix the return fuel from the injectors with fresh supply from the fuel filter.
why would mine not run with this fitted?

What is its purpose??

any i deas please

thanks

alastair

jeremy · Unread post by **jeremy** » 28 Jan 2006, 17:55

The bosch pump will draw in air from leaks in the leakoff pipes - the Roto-diesel just leaks happily away and smells. So if you've got a Bosch pump all the leakoff system must be in good order.

Stewart(oily) · Unread post by **Stewart(oily)** » 28 Jan 2006, 19:37

I was replacing some leak off pipes to my Volcane today and it does not have the piece you describe, the pipes leapfrog from injector to injector then a longer one goes onto the return to tank line, the system is supposed to get rid of air bubbles using this system, your early start misfiring/smoke could be a little air leaking into the system overnight, try squeezing the priming bulb before attempting to start the engine, if things are improved then start looking for the leak.
Stewart

Dave Burns · Unread post by **Dave Burns** » 29 Jan 2006, 10:11

The gismo in question is an automatic bleed valve, they are prone to failing and are best got rid of.

The valve gets contaminated and doesn't seal properly, if its new and doesn't work it might be upside down.

Dave

8304 · Unread post by **8304** » 30 Jan 2006, 08:24

hi

i tried blowing down each of the pipes leading into the unit but there wasnt any resistance, it just seemed to be a junction box to connect the four pipes - would you expect there to be a valve of some sort inside??

i might cut it up and have a look inside!!