Distributor Test Bench

[Jolls]

Hi Team

I am about to construct a distributor test bench and finish off the generator test bench now that I have "retired" from the building game. I am still running our excavator business but it is much less on the tools so I have a bit of time on my hands. I am cobbling the bits together at the moment - 2"/50mm three jaw lathe chuck with 5/16"/8mm drive, 8mm drive coupler, 8mm spindle shaft with supports, 2:1 toothed pulley set, 12V 3000 RPM motor, a 12V PWM motor controller and a motorcycle timing wheel as the timing guage.

As the advance curves in the shop manual are in engine RPM so my plan is to have the dizzy running at half the drive motor speed and take the advance readings off the timing wheel that will be sandwiched between the pulley and the motor drive shaft.

I may need to find a different motor down the track as the advince curves run out to 3600 RPM and the bits I have pulled together stop short of that - but it should bea good proof of concept. I will couple it with a tacho to confirm RPM (at the dizzy) and a 10 in 1 analogue engine analyser to start with (dwell/RMP/volts Ohms etc). I am also about to pick up a working Bosch engine analyser from a workshop that has closed down (2 in fact) both have scopes so will be able to track primary and secondary voltages, test condensors etc.

Give I am still in the planning phase the time to make changes or adjustemnt is now. Have I missed anything? Any thoughts on how to improve the concpet would be greatly appreciated. I will document the parts and build as I go for anyone else to follow down the track.

Cheers n Beers

[Jolls]

I have the the variable speed drive and the 12V motor working. The motor is rated at 3500 rpm at 12V (no load) so I decided to use a 14.5V supply to get the addtional speed I need to take the required advance curve readings once it is together. I don't have a way to measure the rpm as yet so will have to build it and see where it lands once friction and torque losses are taken into consideration. the VSD will also allow me bring the dizzy up to speed in a controlled manner so I don't need to overcome the mechanical shock on start up. I have included a flexible drive couple as a safety net though.

The drive shaft has yet to arrive so I will hold off on constuction of the frame to mount the machine until it does. I have the third string dizzy on the bench - it doesn't turn so I am looking forward to the challenge of trying to bring the old girl back to life. Still haven't found the body for the one I was in the process of restoring so I will use the dizzy off the grey with the leaking welch plug as the guinea pig.

[Jolls]

I knocked up the test bench and ran it trough its paces today. All works fine - I have to make up a front and rear cover so I can keep the dust out and to mount the switches and dials. I have a small tacho to be added so I can keep track of engine speed and then it is simply a matter of using the machine to set the dwell and then graph the advance curves to see how they compare to the manual. Not a difficult build, biggest problem being that 8mm from some Chinese suppliers is different to 8mm from otheres. I hat to turn a couple of shafts down a little to connect them but apart from that ittook about three hours to knock up.

At the moment it is made out of timber - in time I may make the fram out of metal, but for now this suits my needs. Time to try and saved the seized dizzy from the scrapheap.

It would also be great to chat with someone who has experience with triple SU's on a grey and the requirement, or not, to adjust the advance curve.

Picture and video below showing the setup I used as proof of concept (less the coil etc).



https://youtube.com/shorts/uDwIQ4_951s