Knee Action Shock Driveway Bounce Test

I am trying to assess the condition of my knee action shocks on my recently acquired 1949 76C. I know there is the old test for tube shock cars we did at home in the past - push down on a front fender corner (or rear corner) to get the car rocking strongly and then let off. If the car went back to motionless in three up-down cycles your shocks were ok. I know the '49s were softly sprung when new but is there a comparable test for the knee-action shocks? Mine returns to rest after four up-down cycles now.

All four shocks have fill plugs in them. Be sure they are topped off. Use hydraulic jack oil with a oil squirt pistol to fill while lightly moving the car up and down to work any air out. You will feel the resistance increase if they were low.

In the rear, I like to lie on a creeper and pull down on the frame rail with each squirt.

This method doesn't take long and you know fluids levels are correct. Clean the shaft entry points and watch for leakage over the next week or pull the plugs a week later and double check.

Bernie

All four shocks have fill plugs in them. Be sure they are topped off. Use hydraulic jack oil with a oil squirt pistol to fill while lightly moving the car up and down to work any air out. You will feel the resistance increase if they were low.

In the rear, I like to lie on a creeper and pull down on the frame rail with each squirt.

This method doesn't take long and you know fluids levels are correct. Clean the shaft entry points and watch for leakage over the next week or pull the plugs a week later and double check.

Bernie

Thanks for that but they are all topped up. I am just trying to get an idea of what the factory suspension was sprung like. I know it was soft and "floating". Is there a sort of standard like I refer to above for normalcy?

I always thought, "back in the day", it should bounce no more than twice. I have a '50. To be sure not to mislead, I just went out and did the test. Tried each corner. Pushed down with knee on bumper and hands on fender. Each returned up high and settled back down to level. So once up and 1/2 down.

Ben

Thanks, Mr. Bruce. That's what I was wondering about. Have you re-one your front end with rebuilt shocks and new springs, I suppose?

Thanks, Mr. Bruce. That's what I was wondering about. Have you re-one your front end with rebuilt shocks and new springs, I suppose?

Following the instructions in the shop manual, checked the ride height, therefor the spring tension. Results fell right in the middle of the specs. So did not replace the springs. I sent the shocks to 5 Points [Five Points??] in California for rebuild.

Ben