Message text written by "Bromiel, James E (Jim)"
>I need help solving my 74 TR6's backfiring through the carb problem .
I've
had the car
since Nov. I've rebuilt the carbs and added Pentronics Ingnitor electronic
ignition.
I've also replaced a leaking vacuum line. The EGR valve is off and plugged
by previous
owner. The one vacuum line goes from the distributor to the bottom of the
back carb., all
other vacuum lines are capped. The timing is set at 4 degrees ATDC at idle.
I notice the backfire under acceleration / lower RRM or when
cruising at a constant speed.. Under heavier acceleration /higher RPM I
don't notice any
backfire. My first thought was I need to lean out the mixture. I did that
by
turning the mixture
adjustment tool clockwise, hence lowering the needle into the carb body,
letting less
gas through. Is this correct?
<
James,
Try the easy things first. My car had this symptom for several years.
Then after playing with the mixture, timing, plug wires, etc. etc etc. I
regaped the plugs to spec and lo and behold the problem vanished! Duh! So
check the plugs and gap them to .025 - not .035.
BTW clockwise is richer. There is a reverse thread in there that confuses
us guys who try to guess which way to go.
Dave
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