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Tri-Carb Throttle Controls

Healey Nut

Luke Skywalker
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So I’m trying to piece together the puzzle of linkages and rods for the throttle controls on the 62 .
Ive been referencing the two pics , one from Moss parts breakdown and the other from a nice engine bay found online .
Im pretty sure I have all the parts but the one which is confusing me is the rod that goes into that bushing mounted on the bulkhead .
I have the bushing ,and it lists the same bushing for all the 3000 series cars (item 85) . It’s rubber with a removable brass/bronze bushing .
The rod I have in my parts collection (item 60 Moss pic) doesn’t fit into the bushing in the bulkhead it’s too big . If I remove the brass/bronze bushing the hole in the rubber is a perfect fit for the rod (item 60) .But that can’t be right to just remove the bushing and have the rod sit in the rubber ?
The secondary rod which fits into the aluminum bracket on top of the centre carb is the correct size to fit in the bulkhead bushing .
What am I missing here , is it a different bulkhead bushing for the Tri-carb , do I have the wrong rod assembly .
Anybody with a tri-carb can you tell me if the diameter of the rods items 60 & 67 are they the same or is the bulkhead rod slightly larger ?
 

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Just measured mine and both rods are the same at a nominal 0.315 inches. The bulkhead bushing appears to have a metal bushing in it as well. Can't see the bushing but I can feel it with the tip of a knife.

Hope this helps.

Paul
 
Tks for measuring that Paul .
I have checked the size on mine and the rod that goes through the bracket mounted to the centre carb is .315” however the rod I have for the bulkhead bushing is .375” the same as the cross rod hidden away under the bulkhead .
I don’t have any other linkages in the boxes that I bought the car in so I can only assume it was actually being used .
New replacements are unobtainium so I will wait until the engine is in and carbs on to see if indeed ” the wrong linkage “ will do the job then I will machine down the portion that goes into the bulkhead bushing .
Don’t know if it makes a difference but my car is car #14268 with HS4s . Heritage cert matches all the numbers I have for the car .
 
Glad to be of help. I doubt the VIN makes a difference and yours is about 3200 before our HS4-equipped #17466. I don't have the cert but have been lead to believe it was a January 1962 build.

Yes, machining the bulkhead rod may be your best bet. I poked the bulkhead fitting a bit closer and oddly enough, the 0.060 "oversize" you are seeing is about what i would say the metal bushing is. As an alternative, perhaps you could make a Nylon or similar "plug" to fit into the bulkhead fitting and drill it to fit your shaft. Not sure what came first - the Tricarb throttle linkage or some of Rube Goldberg's best work.
 
So after some grinding and careful filing the oversize rod now fits the bulkhead bushing nicely .
what Im looking for is a clear shot of the linkages on the side of the footbox LHD car showing the angles of the various levers and rods .
I think I have it right based on the Moss pic but that’s for a RHD car , it would be a whole lot easier to correct and glaring mistakes before the engine goes in .
 
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