Any advice on booming down a 500-T Lima with a 85% load? Straight boom down with engine @ idle gets faster than I like and makes for an uncomfortable stop! Tried booming up position with engine idleing hoping to back up converter reversing geartrain like it does when hoist down with heavy load but that diddent work, The boom still raised. Boom down & Hoist up works for short shots but even with 6 parts in the hoist it still overruns the boom. My riggers and myself appreciate any help with this!!
You have to use another function to stall the torque. When you said you used the hoist up and boom down together did you leave the hoist brake latched down? Normally the brake is tight enough to stall the torque conv. Step 1-pull in hoist up lever,stalling the conv. Step 2-push boom lever to boom down, nothing should move. Step 3- use the hoist lever that is in, feather the hoist lever forward controlling boom speed, when you want to stop the boom pull the hoist lever all the way back stopping everything. Return boom lever to neutral. Are you using both hoist drums? If not tighten up the one your not using Tight to make sure it doesn't pull through and use it for boom control. You can also use the swing frictions if you have a swing snubber on the lever. Engage the swing brake and then use the snubber ,pulling in the swing clutch to stall the conv. You must have a good swing brake for this to work
Thank you for the reply. I never thought to slip the hoist friction to control shaftspeed! My front drum is not being used so I will tighten and use that.
Had to unload a 16,000lb forklift off a dropdeck this morning, perfect time to try this. I tightened the brake on the unused front drum and everything worked perfect! Found that by placing my right thumb on the end of the front drumshaft and controling the airvalve with my left it was very easy to inch down on the boom. Thanks again for the advice!
Good advice Kat09 , I remember those Lima's had a quick boom!