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Instructions for mounting the modular quadrant and controls.
Mount the quadrant.
Some thoughts on this: the modular quad body is very rigid, and not all the
spacer stacks are necessary. The cross rivets offer lots of possibilities
for making the mount. The simplest is just to use thru bolts. We provide two
clear spacer stacks for these bolts, but you can, in fact, use any of the
stacks. The only requirement for the stacks, is that you have at least two
rigid cross bolts (or rivets). This means, for example, that once you mount
the quad body with two rigid thru bolts, all the other stacks could be re-
moved. This also means that the two thru bolts can be located at any of the
Also, the three inch stroke output of the quadrant is available only if the
controls are mounted directly in line with the output line.
If, for example, the quad body is mounted at some angle from the horizontal,
and the controls are horizontal, the output will be less than three inches.
The simplest mounting scheme would be to mount the quad body between two
angles, and the controls can be mounted by using our mounting block, bolted
right to the top of the angles (as shown in the drawing).
Plan the quadrant end control mounts.
Note that there are two types of standard sheath terminations: a 7/16-20 x 1
1/4 inch stud and a grooved termination. The stud is usually mounted
through a bracket with a jam nut on each side. The grooved termination can
be secured with a simple U Bolt, a bracket with a slot cut in it, or some
other type of clamp. We suggest you use the 1/8 x .25 diameter Clip Groove
termination. We also have custom clamps available to simplify the mounting
The location of the controls is fairly critical to get the proper stroke and
not have interference of the stud and spacer stacks. The dimensions shown on
the drawing are dependent on the following:
a) a reach (of the control end) in of 5 1/4 inches, and,
b) the length of the clevis.
c) the clip type sheath termination is used.
Control location will have to be recalculated if your hardware is different.
Plan the mounting of the controls at the engine end.
We have standardized specifications for the reach of the core stud at each
end. Both ends of our engine controls have a reach of 5 1/4 inches in and 8
1/4 inches out. The stroke of the control is 3 inches. These particular di-
mensions are used in most OEM engine control applications and are already in
production. We strongly urge you to use these parameters as custom parts
cost considerably more.
When using our standardized controls, the sheath terminations will be lo-
cated at predetermined positions.
The end of the control stud at midtravel is 6 3/4 from the clip groove. You
have to know what type of connection you will be using, such as rod end or
clevis. The reach of the fully assembled end (at midtravel) will be: 6 3/4
plus the length of connector minus about 1/2 inch of stud thread inside the
The drawing shows how this is done. Do your planning with everything in
mid-position, and make sure you have enough stroke available.
Measure the length of the control sheath.
Keep these fundamental points in mind:
1) The sheath does not move and is fixed at both ends, we will call these
point A (the quadrant end mount) and point B (the engine end mount).
2) The sheath must be long enough to comfortably reach from point A to point
3) The moving core has studs at each end.
4) The studs must reach from the sheath fixing points (A & B) to some lever
Determine the length of the sheath:
You need to know how long the sheath must be to make a run from one fixed
point to another. In the case of an engine control, this would be from the
vicinity of the quadrant to some location on or near the engine. To get the
proper length on the sheath, the easiest thing is to put heavy copper house
wiring (Romex) in the run. This wire is fairly stiff but bends easily and
won't take unintended shortcuts. Mark the bulkhead or fixing positions
(where the sheath terminations are going to be) on the wire with a large
magic marker. Remove the copper wire,straighten it out and measure between
the marks to determine the proper length of sheath.
The reason this works well is this: consider a run that is 20 feet. If the
sheath is too short, it can't be installed because it won't reach the two
fixed points, but if the sheath is, let's say, 3 inches longer, it probably
won't matter at all. What is important is that 1) the sheath can be properly
installed and follow the path needed and 2) the core reaches it's proper po-
sition at each end. The core doesn't really care how long the sheath is,
and up to a point, a variation in the length of the sheath does not change
the operation of the control at all, as long as the sheath is long enough to
be installed properly without excessive extra length to get rid of with
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