Sunday, June 7, 2015


 Mass production time again! Here are six [of eight] Bosch distributors for Saab V4 cars, completely disassembled, and with a zillion miles worth of grease and crud cleaned off. They are ready to have the bottom of the distributor housing rebushed. The housing "hogs out" at the bottom, with age and a jillion miles of useage. This wear causes the point gap [thus the dwell and the ignition timing] to fluctuate and the engine runs like crap. Note that the second housing from the right already has a steel bushing installed.
 I use a bronze bushing...BUT...first the distributor housing must be reamed to a certain diameter.  It is essential that the distributor be held perfectly square and the tool that I made [which is in the lathe chuck in this picture] does that job. You can see that several distributors have been drilled, thus the pile of aluminum FUZZ on the lathe bed.
 You can see the bronze bushing set in place, just ready to be pressed into the distributor housing.
 Once I get the bushing in place, I have to ream it to the shaft size, plus 0.003". This is a tedious process, but doing the job with a hand reamer makes sure I get the correct fit. Every distributor is a LITTLE DIFFERENT and has different amounts of wear--remember--these suckers are about 50 years old! 
 You can see the five distributor bodies with bronze bushings and the one with the previously installed steel bushing here.  All the shafts have been fitted and they are ready to go back together again. Now the REAL work starts, as the points advance plates must be fitted and adjusted, a vacuum control unit fitted, and then the assembled unit has to go onto the SUN distributor test machine to set the advance curves.  This usually means I get to take the suckers apart 2 or 3 times to adjust the mechanical advance gubbins to get the correct advance curve.  Swearing usually helps. Quite a lot of swearing helps quite a lot more. 
All eight completely reconditioned distributors are shown here. These all have points and a condenser installed. If the customer wants a Pertronix unit, I take out the points and condenser and install the P unit. Then I add a rotor, a cap and a new set of spark plug wires, and the bugger is ready to go into the customer's V4 engine, for another 100,000 miles.  Good stuff!