3000 Hydraulic pump losing prime

(quoted from post at 13:29:51 05/07/12) This is kind of an update from a prior thread. Air is finding a way into my
hydraulic pump. I have replaced all the pump gaskets and o-rings and torqued everything to spec, and I still have to bleed the pump if it sits overnight.

Where can this air be coming from? I can't find any leaks in the lines back to the sump or any leaks from the pump.

Any suggestions for where to look is appreciated.

John.

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(quoted from post at 11:03:57 05/07/12)

(quoted from post at 13:29:51 05/07/12) This is kind of an update from a prior thread. Air is finding a way into my
hydraulic pump. I have replaced all the pump gaskets and o-rings and torqued everything to spec, and I still have to bleed the pump if it sits overnight.

Where can this air be coming from? I can't find any leaks in the lines back to the sump or any leaks from the pump.

Any suggestions for where to look is appreciated.

John.

Click to expand...

id you replace shaft seal?

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(quoted from post at 13:52:09 05/07/12) John,
Your suction line (the larger diameter line) is sealed with o-rings at both the pump and sump. This is a negative pressure line, so you may not see any fluid leakage or maybe some very minor fluid wetness. As a test, try putting silicon sealant externally on these connections as a backup seal. Also look for any sign of wetness along the suction line - you might have a hairline crack.

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