OK Jack...here goes. It is a lot of steps and I will give you some
simplifying adjustments to lock out very fine tuning for now.
First, even tho it should be at 4 degrees, set the timing for zero degrees
RUNNING (not static) with all vacuum lines connected at carbs and at
distributor. All timing is done with the vacuum lines connected and the
engine running at op temp. (Unlike static timing the TR3).
Second, lets run thru key elements of the rebuild before we adjust.
Assume we replaced the throttle spindle shaft seals (with lips of seal to
outside of body) and the shafts are not excessively scored AND we did not
spray carb cleaner on these seals (which rapidly eats the lip seal and
creates a nice vacuum leak (Unlike bushed SU type carb bodies).
Set the float level by inverting the carb body (Check that the float mount is
solidly riveted to the body yet) and bend the float tab until the seam on the
float body is level (parallel) to sight with the (now) upper surface of the
carb body (both surface and this line should be parallel). Actually more
accurate than the paper float gage in the kit.
Next screw the large brass trim screw into the side of the body (for now)
Next, take the airhorn with needle installed and invert it and sight across
the surface with the needle protruding and adjust the needle up or down until
the delrin washer at the base of the needle is flush with the surface. (A
neutral setting)
I assume you did not unlock the float bowl vent adjusting screw adjacent to
the idle setting screw. This adjustment screw is held in place with a nyloc
jamnut. If this has been moved there is more to do. This screw sets the float
bowl vent anti run on feature of the carb. If it has been moved let me
know....we'll back up a bit.
Next, I assume you checked the decel valve diaphram for cracks and leaks and
replaced the diaphram if necessary (it does not usually come in a standard
rebuild kit...neither do the throttle spindle seals mentioned above
previously). Now let's lock this device out from the initial running
adjustments as it is a MAJOR vacuum leak if it "pops off" above idle.
Soooooo....remove the small brass freeze plug in the end of the cast hex
shaped body (visible externally and covers a small screw head from the
outside). With the proper gasket set installed (match the one removed...there
are three variations in the kit usually and a small internal "O" ring in the
kit for this rebuild of this device) turn the screw head clockwise until it
bottoms. Then turn the tiny screw head externally counterclockwise EXACTLY 10
full turns. This provides max preload to prevent pop off (also makes a nice
idle drop on decel) without dislodging the screw body internal to the hex
casting (trust me).
I assume you have installed both the internal AND external seals on the temp
compensator. (Round "O" ring inside the carb body cavity and flat "O" ring
between the 'arm' of the compensator and the carb body).
And now install the airhorn and fill with 20-50 engine oil and install the
damper.(Making sure that the airhorn holes at the base are towards the engine
and that the daiphram tabs all line up). Also make sure the carb top is on in
correct rotation (Small tab towards aircleaner box....not so you can read
STROMBERG)
Disconnect the coupler (seperate the throttle shafts from each other).
Unscrew the idle screw until the butterfy closes (assumes the butterfly is
right side up in the throttle shaft and does indeed close (the water check
helps here upon assembly) and then screw the idle screw in 2 1/2 turns on
each carb.
We now have a datum setting.
Try to get the car started but do check that the vacuum lines are correct (I
provided the diagrams in the moss motors TR6 catalogue years ago and still
think it is the most accurate ...also drew the sketch of the damper "O" ring
seal...that's another story...smile) but check the operation of the EGR valve
by removing the vacuum line (engine off) reach under the metal EGR body and
pull up on the daiphram expelling the air....place your thumb over the vacuum
nipple....release the diaphram you pulled up....then release your thumb. IF
the diapharm dropping has created and is holding any vacuum (which is
necessary for EGR operation) it will "suck" air as you remove your thumb from
the steel vacuum nipple. If the is NO SUCTION block the device off again to
get this car running (Steel ball in the vacuum fitting or cap it off for
now.(But DO block the other end of the line as well....NO vacuum leaks
allowed to get things started.)
Start the engine......the objective is to keep the RPM under 1000 (to
preclude "popping" the decel valve. Use your ear and rubber tube or UNISYN
airflow and adjust the idle screw to get a balanced airflow. THIS IS MUCH
MORE IMPORTANT THAN THE FUEL ADJUSTMENT FOR NOW.
Once the airflow is even, shut off the engine and couple the carbs (but note
to center the 'dead pedal' link in the middle of the carb linkage...this
permits some dead pressure on the pedal without affecting idle and tiring
your poised ankle...smile). It also prevents bottoming of the throttle link
adjustment during final fast idle adjustments.
Star the engine again...and now move both idle screw up or down equally to
get the tach to 850PRM. Then 'blip' (Lift) the airhorn in either carb and
check for lean or rich. This is classic via SU adjustment however much less
sensitive so listen for minor RPM increase (perfect) or rapid stall (lean).
Insert the adjusting tool in the top and turn Right for Rich and Left for
Lean (Looking top down on the carb). But if it takes more than a full turn to
get close to proper fuel setting there is something wrong here and we need to
chat more......and there is LOTS more to consider.
I know you have probably have done 99% of all of this so apologies for
starting with the basics, but sometimes going thru a logic tree or sequence
clicks for me. Hope that 1% that helps shows up.
If the float bowl vent needs resetting let me know. Hopefully it was the
timing?
(I rebuild these watching television!!)
Bill Burroughs
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