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[300SD] Manual throttle adjustment

Started by Ilike300sd, 22 September 2011, 06:41 PM

Ilike300sd

Seems like it wouldn't be that difficult to add a manual throttle adjustment.  It's just a cable that goes from the dash and pulls on the throttle, just like how the cruise control does.  So it looks like 4 ways to do it would be:

1) expensive/best method: replace current plate that holds the cruise cable with an oem 79' one that has spot for both cruise and throttle adjustment cables, add oem throttle cable, add oem knob.  79 plate and cable shown below.  Throttle adjustment cable is highlighted in yellow

2) medium expense, special circumstances: if your cruise control doesn't work you could just remove the cruise control cable and use that cable location.  You could add an oem cable and knob.

3) cheap, special circumstances.  same as #2 but use a universal manual choke cable and knob available for cheap from any auto parts store.  Run cable under dash or, (YIKES!) through dash. 

4) ghetto: Buy a universal manual choke and knob and drill a hole in plate above existing cruise control cable (at red dot in pic below)  I believe the universal choke has a sleeve with adjustment threads so you would'nt have to make threads on the plate (you'd have to check in the parts store to see if it does).  Cut a slot at the red X for the end of the cable or fashion via some other method to hold the end of the cable.  Pretty hinky but functional.  I'm assuming the 80' one loks like that shown in the lower picture.  Actually, now that I look at the 80' picture, is there a hole already there to the right of the cruise control cable (barely visible)?




Ilike300sd

#1
If the mounting plate for the cable on an 80 turns out to be the same as the 79 (It sorta looks like it from the pic) and the throttle cable has simply been removed then of course it would be a piece of cake.  Just add the oem cable and knob or add a manual choke cable/knob.  Someone would have to check their mounting plate and see if it has holes for 2 cables or just one.  However, is there some automatic idle control that would overide the manual one?  I'm guessing no?

Casey

#2
Looks like the hole is still there:



I think maybe I can see the other hole in this picture:


Ilike300sd

It looks like the throttle adjustment cable is held with a simple metal clip.  The clip goes in the rectangular hole seen on some of the photos above.  So to do oem you'd need the cable retaining clip, cable with adjustment nut, and knob, and to be anal probably a rubber grommet at the firewall... Here are some pics:








Ilike300sd

Just wanted to update this post fyi.  I adjusted the idle screw and this thing idles SOOOO much better now.  I set the screw to idle at about 800 rpms and increased the manual cable adjustment so it can idle at about 1600 max (800 min).  Sooo much better.  Car used to shake etc. when I bought it because idle was really low.  It even vibrated one of the nuts of the attachments for the air filter. 

The idle screw is located on the back 1/3 of the injection pump.  It is located between the pump and the engine.  It has a 14 mm locknut which must be loosened with a 14mm deep socket.  Then you can increase or decrease with a slotted screwdriver and re-tighten the locknut.  On my car the screw was a long ways from where it should be.  It wasn't even contacting the metal part for which it is meant to act as a "stop".

Next up will be the diesel purge and valve adjustment...

Casey

Quote from: Ilike300sd on 27 September 2011, 10:15 AM
Just wanted to update this post fyi.  I adjusted the idle screw and this thing idles SOOOO much better now.  I set the screw to idle at about 800 rpms and increased the manual cable adjustment so it can idle at about 1600 max (800 min).  Sooo much better.  Car used to shake etc. when I bought it because idle was really low.  It even vibrated one of the nuts of the attachments for the air filter.

Next up will be the diesel purge and valve adjustment...

You might also want to look into replacing the motor mounts and engine shocks.