Throttle valve basic setting....

[wasserleaker]

As the maual says, 'Do not adjust'
but i'm pretty sure the MOT man adjusted the stop screw to alter the tickover speed instead of the air screw on the throttle housing, does anyone know where the edge of the flap should be in relation to the small vacuum pipe hole in the housing when it's set correctly??
the hole is currently slightly uncovered when the valve flap is shut, should it be closed off by the edge of the flap when the throttle is fully closed? cheers for any help.
(2.1 DJ Digijet engine)

[Red Westie]

I don't know specifically but I do remember the housings generally were prone to sticking after years of use and with the build up of carbon etc..
We would remove the housing, clean off all the build up with paint thinners, take the throttle screw back so the butterfly was resting in the housing (this would create a sticking action as the butterfly cuts into the housing) now screw in until it JUST touches and add a fraction of a turn (basically as shut as it can be without sticking) just be careful as the vacuum does tend to suck closed, just be sure it isn't set too closed that it sticks.
Martin

[wasserleaker]

Many thanks Martin, mine seems to have worn a bit both on the flap and the housing, and does indeed stick slightly when closed, the spindle seems to have some play/float in its holes too which may be why i cant get the tickover low enough, may be sucking in too much air when the flap is closed, even with the air screw fully closed the idle speed is too high, double checked timing and its spot on, wondering if the vacuum diaphram in the dist. is working ok or if it isn't retarding properly at idle, as when the timing was wrong (not advanced enough) it ticked over fine at around 800rpm!

[sandwedge]

The green book says "adjust screw till a thin piece of paper will just about drag between the end of the screw and the main body".

You will probably need to check your throttle position switch as well.

[wasserleaker]

just found a vanagon website that mentions the paper drag method sandwedge!
it says....
adjust the screw outward so there is a gap, then screw it in against a piece of paper until you can just feel the paper drag, then turn in half a turn
and as you say, re-adjusting the throttle pos. switch then would be a good idea

[sandwedge]

Just been through this on my new van.
Getting the stop screw adjusted not a problem, adjusting the stop sensor what a pig, I think the adjuster cam on mine maybe knackered by someone in the past, got there in the end though, runs good know, also had to adjust timing and tick over RPM, the engine was firing about 20 deg after TCD, what that all about?