The specialist glued weights between the fins of the 4 drums in order to eliminate their big imbalance. There is not much space between the braking drums and the rims. He used Weicon HB 300 adhesive.
Balanced Drum.jpg [ 80.37 KiB | Viewed 1340 times ]
High temperature resistant to 392 °F.
Short term up to 536 °F.
It is said that normal operating temperatures
for drum brakes range from 150 °F to 400 °F,
but under hard breaking conditions temperatures
can exceed 600 °F.
Test drive result up to 75 mph:
Vibrations are still there, but less intense. I hoped so much that they were gone forever.
It seems that they are getting lesser when driving over 60 mph. Holding the Revcon at this speed is now almost possibe without the feeling of the vehicle falling apart.
This has improved.
Now with balanced drums I want to try wheel balancing on the vehicle again and see if it shows a reduced imbalance which maybe could be eliminated with some extra weights on the rims.
When I tried it the first time in April the imbalance was too high.
Last option: New tandem and new axles fitting for a past 1982+ Revcon, new rims, new tires in the rear which would be about 10.000 Euros/3 months time in Switzerland.
My swiss specialist could do the job in cooperation with a DAF Trucks repair shop.
I haven' t found anybody in Austria or Germany who would be able to handle that kind of job.
I am reaching the end of the line.