2 stage pump stuck in low gear

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nickblaze466

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I built a splitter about a year ago for a buddy of mine, and it now belongs to me. he's moving, i bought it...

it still splits fine, but i noticed its running slow. as i put some of the bigger logs through it (i've only run it maybe 20 minutes) it clicked that i didn't notice the pump dropping into low gear to muscle through some of the nastier logs.

my question is, what would cause a two stage pump to lock itself in low gear? i've gone over the hydraulic system, but can't think of anything that would cause that issue...sticking in the first stage could be a valve problem...but nothin about being stuck in low.

anybody have any ideas, or is the pump just shot?
 
The unloading valve has a (1)broken spring,(2) crud stuck under it, (3) rust or a burr holding it open. pull out, check, clean reinstall and adjust.
 
okay, thanks for that info.

on to step two - where is it, how do i get to it, and where do i get barts for it once i figure the problem?

i've never taken one apart before - never had one screw up.
 
First , A 2-stage pump must be understood. It has two sections, the low volume/high pressure section ( low gear) is always moving fluid ,the high volume/ low pressure section ( high gear) bypasses at 600 to 800 psi no longer adding fluid to the system.

If the pump looks like the one below the hex cap to the right of the suction tubecovers the bypass adjustment.

67a1_1.jpg
 
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check to see if the keyway is broken..
mine did not fuction properly a few years ago, the key way had broken and the insides of the pump were kinda nasty, it worked but would'nt go to stage two (low gear)
put new pump on, bowt a hundred bucks for a barnes 11 gal. min. if i remember correctly ??
 
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