Boom functions valve leak

Problem: leak produced from closed reservoir tank valve.

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This is the “boom functions valve” and the arrows show the place where a major leak has developed after powering up the machine when the tank reservoir shut off valve was left closed by accident.  Obviously the pic does not show fluid flow.  When under power the leak outputs a stream that would fill your coffee cup in about 2 seconds. Make repairs with the valve body in place or remove the assembly for bench work?

Repairs require the valve be removed.  5 individual seal kits are used, part# 352-29006 (see pic below).  Note: as suggested by the Altec tech rep, stand the valve on end when disassembling so the ball bearing parts do not fall out and go everywhere.

booms function valve

One thought on “Boom functions valve leak”

  1. After pulling the complete booms function valve assembly out and replacing all the seals as advised by Altec, I fired up the unit only to have the same leak in the same place so it was not the seals. The only good thing about the experience was going through the work and becoming familiar with the equipment. I understood a lot more about how the valve works and also how the pilot and MOR (manual override knob) valves work. There was only one other possible source for a leak at that point, either one of the MOR or pilot valve bodies were cracked or broken or their gaskets were leaking. I took both out on each side of the leak and found a blown out gasket under the first pilot valve body. Wish I would have had an x-ray machine to start out, it would have saved a lot of work but then again, learning the hard way really is the best way when it comes to making repairs like this. You hate to go through all the work and headache but, your confidence in understanding is well worth the effort and when you find the actual problem instead of playing guess work, it’s a relief knowing the problem will soon be history.

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