Ron Wrote:
It's easy to see the various rods turn and
move when you push the throtle peddle but you don't see any movement when
you pull the throttle peddle back towards you past it's neutral position.
We
did this over and over switching places. It it was the rod behind the
manifold just above the bellhousing you would see it turn inside the clamp
but it doesn't.
We both feel that the problem must be where the pedal shaft dissappears
into
the midline of the car just above the trans cover.
Ron,
If one of the clamps is slipping, then the linkages and carbs would go, say,
half of their full travel when the pedal is depressed.
when you release the pedal, the carbs and linkages return to the Idle position
because of the springs on the carbs. -At that point the linkages are in the
fully returned position, but the pedal is still halfway down? The linkages
cannot "return' any further, because they are up against the stops in/on the
carbs at the idle position. If everything were tight and not slipping, you
would not be able to pull the gas pedal up any further without really forcing
it. The fact that you can pull the pedal up, and nothing under the hood moves
indicates that the clamp that is slipping is the one where the pedal shaft
exits the driver's footwell and enters the engine compartment. Think about it,
when it is working properly, and you push the pedal, the horizontal part of
the pedal shaft turns about 30 degrees! -or less than a tenth of a rotation.
ANY slippage will cause what you are seeing.
The pedal shaft, where it enters the engine compartment, and where the
clamp-lever attaches has a small cutout ground into it's side, which
accommodates the shaft of the bolt through the clamp. This assures the proper
orientation of the lever, and HELPS to keep the lever from slipping when the
shaft is turned. If the clamp is slightly loose, the lever can still slop back
and forth to the limits of the tolerance between the bolt and the pedal shaft.
The linkages would move, but the would not go full-travel, and the friction at
the joint between the lever and pedal shaft would prevent the pedal from
returning fully, and from returning to its proper orientation to the lever,
-requiring you to pull it back up.
The primary problem is that the clamp is too loose. It can also be exacerbated
if the cutout on the shaft is worn/enlarged or if the bolt through the clamp
is smaller diameter than originally intended.
I don't know about the lever on BJ8s, but the lever in question on the BT7 is
a somewhat cheezy affair made of sheet metal, and isn't meant to be tightened
down too many times, before it deforms and becomes useless....
DON'T ASK how I know all of this... Just TRY changing the pedal and shaft,
and that lever in a tricarb sometime!
David W. Jones
'62 Mk II BT7 tricarb
Cumberland, RI USA
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