ZX 1.9td - Fuel boost adjustment

sooty · Post by **sooty** » 03 May 2004, 23:43

I've had all the info/photos regarding increasing the power from a 1.9td with a mechanical pump. I've adjusted the boost and OK, done the fuel internal increase and OK, but I want adjust the boost fuel to lower the amount. But how do you remove the plastic cover to get at the 14mm locknut, I've tried to prise it off without any joy and I don't want to damage it too much.
I've tried a thin flat bladed screw driver to prise from behind the cap against the dish cover but all I do is scrape along the side of the plastic cap.
The reason for wanting to adjust the fuel boost compensator is to reduce the fuel boost as it tends to Black Smoke when on boost above 3000 rpm.

sooty · Post by **sooty** » 06 May 2004, 11:08

Looks like I'll have to else where for the tip, Derv Doctor?

rossd · Post by **rossd** » 06 May 2004, 13:15

If the car is smoking when on boost, you want to reduce the on-boost adjustment, which is the diaphragm. Adjusting the screw under the cap on the top of the pump will have no effect here as this only adjusts the fuelling when off boost.
Take the top off the pump (4 screws) and turn the diaphragm anti-clockwise. This should reduce the fuel on-boost.

sooty · Post by **sooty** » 06 May 2004, 22:12

The Lucas fuel boost compensator is on the side of the pump facing forward towards the rad and the off boost fuel adjustment is internal again on the side facing forward.
This must be a Bosch pump you are refering to.

rossd · Post by **rossd** » 06 May 2004, 23:27

Ah yes it is, sorry I assumed you had the Bosch pump for some reason!