[6pack] Bucking--Jerking TR-6

[Bill Wellbaum]

Well, so many have said that most carburetor problems are electrical and,  the
opposite, that most electrical problems are due to carburetors. So, may '75
TR-6 developed a serious bucking and jerking problem to the point where it was
undrivable.  I hope what I am about say helps someone down the line.

I replaced the plugs and the plug leads.  No improvement.  I then replaced the
points, the condensor, the dizzy cap, the dizzy ground lead, the low tension
block from the dizzy to the coil, cleaned the fly weights and checked the
springs on the retard unit--all to no avail.  I replaced the fuel pump and the
fuel filter.  I removed, cleaned and replaced the primary ground strap from
the battery to the engine block.  No joy.  I then took both Zenith carbs
apart, cleaned them, checked the float levels, put heavier oil in the dash
pots and put them back on the car.  No improvement.  Double checked the
condition of the battery when charging--no problem there.

It wasn't until I took the dizzy out again and measured the wear on the dizzy
shaft that it came to me that the wobble in the dizzy shaft might be the
source of the problem---and the reason the timing would jump 20 degrees when
idling.  I turned the shaft until the cam opened the points and pushed on the
rotor in the opposite direction.  I could close the point gap by doing so.

So,  I had new bushes made up and installed in the dizzy eliminating all
wobble.  Problem solved.  Now, the engine sits and idles smoothly, starts
immediately on the key, and seems to have more power.  I also removed all the
smog equipment and eliminated the vaccuum lines capping off the carbs and
other vaccuum-related openings.  I set the timing at 12 degrees BTDC at 800
rpm--and could not be more pleased with the results.  No stumble, no jerking,
no hesitation, and no stumble at low rpm while accelerating.

Thanks to all those  that made suggestions as to the nature of the problem.

Bill Wellbaum
Las Vegas
baclv.org