Throttle housing setup. It's not clear.
Discussion
Hello All, Now I have my Wedge I'm starting to go over a few things. One area I'm presently looking at is setting up the throttle components for a smooth controllable tick over, and unfortunately the wedge bible is not supplying the answers.
There are three areas for adjustment. Throttle pot, large allen key idle screw and the little grub screw located on the underside of the housing. I would assume the grub screw should be set to stop the butterfly valve from sticking shut, then the idle screw to set the tick over speed, but this is contradicted by the bible saying the idle screw should be set 2.5 turns back from being turned fully in.
So the question is, what should be set in what manner, for the idle & grub screw. Also once this is done how do you set up the throttle pot. Do you set it so it's fully at the end of it's travel, or is it a multimeter job?
Advice please. Regards Andy
There are three areas for adjustment. Throttle pot, large allen key idle screw and the little grub screw located on the underside of the housing. I would assume the grub screw should be set to stop the butterfly valve from sticking shut, then the idle screw to set the tick over speed, but this is contradicted by the bible saying the idle screw should be set 2.5 turns back from being turned fully in.
So the question is, what should be set in what manner, for the idle & grub screw. Also once this is done how do you set up the throttle pot. Do you set it so it's fully at the end of it's travel, or is it a multimeter job?
Advice please. Regards Andy
Grub screw should be adjusted so that with the throttle closed it just nips a two thou" feeler guage at its lower edge.
Idle screw should be wherever gives you correct idle, from memory 850 +/-100 rpm. The 2.5 turns out is probably base setting just to get the car to start.
Throttle pot should output 330mV at idle +/- a bit; needs a multimeter to measure.
Idle and t/pot vary from car to car for best results anyway!
Idle screw should be wherever gives you correct idle, from memory 850 +/-100 rpm. The 2.5 turns out is probably base setting just to get the car to start.
Throttle pot should output 330mV at idle +/- a bit; needs a multimeter to measure.
Idle and t/pot vary from car to car for best results anyway!
The pot is fed with a stabilised voltage (about 4.5v IIRC), with reference to a virtual ground in the ECU. So two wires should measure 4v5 irrespective of throttle position and the third is the variable wiper, which will read 300mV - 4V5 as the throttle opens with respect to one wire, and 4V5 to ~0V as it opens with respect to the other, if you follow.
If it was me, I'd like to see red as the 4V5, green as ground and yellow for the wiper... it being yellow and green you need to read.
Don't use the engine as the earth reference as you may get different readings.
If it was me, I'd like to see red as the 4V5, green as ground and yellow for the wiper... it being yellow and green you need to read.
Don't use the engine as the earth reference as you may get different readings.
Your "2.5 turns out" reference is definitely not related to the large, normally slot headed, idle control screw on the plenum chamber, but the Idle CO mixture control screw, usually allen key head, on the air flow meter. That setting is sufficiently correct to get things going - mixture-wise - before actual CO measurements are taken for readjustment.
Typcally the idle control screw is in the region 4 to 6 turns out from fully home.
Both the adjustments are very dependent upon the idle air gallery being clear of crud.
As for the rest, the grub screw mentioned - as per Wedg1e - is indeed to prevent the disc from binding in the tunnel, but be sure that the disc is well centralised and not interfering at its edges.
And the idle speed is set to the rpm figure mentioned, or thereabouts.
You might want to mug up on all the Efi components, in this archive:
http://www.vintagemodelairplane.com/pages/Rover_Te...
particularly throttle pot and plenum chamber to see how the above answers fit into the overall picture.
Typcally the idle control screw is in the region 4 to 6 turns out from fully home.
Both the adjustments are very dependent upon the idle air gallery being clear of crud.
As for the rest, the grub screw mentioned - as per Wedg1e - is indeed to prevent the disc from binding in the tunnel, but be sure that the disc is well centralised and not interfering at its edges.
And the idle speed is set to the rpm figure mentioned, or thereabouts.
You might want to mug up on all the Efi components, in this archive:
http://www.vintagemodelairplane.com/pages/Rover_Te...
particularly throttle pot and plenum chamber to see how the above answers fit into the overall picture.
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