Need help diagnosing an air grabber issue.

[70 RR]

Last weekend my air grabber was working fine but this weekend it started to open then nothing. I have a radical cam and I bypass the vacuum canister (one of the nipples broke on the canister) and run my air grabber off of my middle carb (six barrel) and never had a problem until today. The air grabber opened about 1/2" and then stopped. I unplugged the hose to the carb and plugged my vacuum pump in and same result. I gave the actuator a little help and when it got a little over half way it took over and opened fully under its own power. Does this mean the actuator is bad? I just wonder if this is typical that one day it works and the next it's kaput? Please, if anyone has encountered this problem feel free to enlighten me. Thanks!

 

[kiwigtx]

I'm not sure what level of vacuum you get of the carburettor port, as I have not tried that. The Air Grabber vacuum feed comes off the extra port on the rear intake manifold outlet nipple (near the firewall) - the one that feeds the Brake Booster.

 

[70 RR]

I'm not sure what level of vacuum you get of the carburettor port, as I have not tried that. The Air Grabber vacuum feed comes off the extra port on the rear intake manifold outlet nipple (near the firewall) - the one that feeds the Brake Booster.

Like I stated above, I was running it this way for the last 8 months with no issue until today. The amount of vacuum from the carb was adequate.

 

[texas69bee]

How much vacuum is require to activate it? Then measure vacuum at the carb. Obviously something is beginning to fail.

 

[1962polara]

Squirt a little oil in the actuator and run it manually a few times to loosen it , it might me a dry seal or a foreign object ?? This should decrease any resistance present.
I always do this to my air tools and it keeps them in GWO.
Goodluck

 

[badlite]

Make sure that there is not something binding.

 

[70 RR]

I lubed the actuator and no change. I bypassed the entire system and hooked my vacuum pump to the bottom nipple of the actuator and the same thing, unless I give it help, it won't open. I am going to take the actuator off and bench test it before ordering the 200 dollar/10 dollar actuator just to make sure but I am 99.9% sure it's the culprit.