Need Help on LucasCAV Throttle Linkage Parts and Adjustment

Gordon Gould · Sep 17, 2014

I did a Lucas CAV throttle and kill shaft seal repair today.
When I got it all cleaned up I could see the linkage was really worn.

Taking off the linkage Layer by Layer

The short end of the spring was somehow lodged in a solid place but on reassembly I can't get it to catch anywhere. I think it goes in the clockwise groove on the lower linkage piece. I am not sure how this is supposed to work but it appears to me the two levers with the spring connection allow the operator throttle control to over travel. Maybe to insure consistant idle and WOT position at the pump ???

Anyway, I am looking for a place to buy replacement parts, especially the spring, or an idea on how to lengthen the spring post. I am afraid to bend it in fear that it will snap.

I also broke a bleeder screw and would like to replace the cap and bleeder assembly w/ copper washer.

The open heart surgery went fine. It is just this linkage I need to fix. Thanks for any help.

If you never saw one inside here it is. New gasket and ready to reassemble.

Gordon Gould · Sep 19, 2014

Well I found out I can get a new lever kit consisting of the two levers and the spring for $135 + S/H. The parts are not sold individually. I decided to try to fix the spring before I did that. Nothing to loose.

I got out the torch and brazed a little bronze on the long leg where it was almost worn thru from contacting the lever. The short side must have worn right thru and broken off.

Then I lengthened the short leg by moving the 90* bend point back a little using as little heat as possible. I thought the heat might ruin the spring but it didn't seem to.

The bottom lever had a hole worn almost thru it where it hit the idle screw. So I put some bronze on that too. After reassembly with the "new" parts the throttle worked like it should.

skyhook · Sep 21, 2014

Looks good, hope the bronze holds up for you.

Gordon Gould · Sep 21, 2014

skyhook said:
Looks good, hope the bronze holds up for you.

Thanks, I hope so too. Bronze has excellant wear resistance (think bronze bearings/bushings) so it makes a good filler for worn spots like the notch worn in that spring and the face of the stop. Only time will tell.

EDIT: And you don't need a much heat to resurface with bronze.