Frequency of hydraulic pump 'clicks'
Moderator: RichardW
Frequency of hydraulic pump 'clicks'
When buying second hand Xantia TD, whats the click frequency (technical term) one be looking for and what rate should sound warning bells?
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- Posts: 6
- Joined: 14 May 2001, 15:42
- Location: Australia
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Hi Alf,
The sphere is a pressure vessel with a bladder inside, the bladder (like a balloon)being pressurised with Nitrogen gas. The LHM goes in the end and "squeezes" the bladder from the outside. It can't make any clicking noises.
The pump does the clicking, but it is turned on and off by the regulator which is where the sphere screws into. The regulator's commands to the pump to switch on or off are determined by the pressure in the system, and the rate of pressure loss/drop inside the system is governed by the precharge in the accumulator. When its precharge is low its ability to help top up hydraulic pressure in the system is reduced, so the pressure drops faster, so the pump has to cycle on and off more often.
Geddit? It's all very logical.
Henry
<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Thanks John D, Could you clarify a point for me? Is it the pump that clicks or the accumulator sphere. Pump = loadsamoney, Accumulator sphere = not too bad.
TVM
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
The sphere is a pressure vessel with a bladder inside, the bladder (like a balloon)being pressurised with Nitrogen gas. The LHM goes in the end and "squeezes" the bladder from the outside. It can't make any clicking noises.
The pump does the clicking, but it is turned on and off by the regulator which is where the sphere screws into. The regulator's commands to the pump to switch on or off are determined by the pressure in the system, and the rate of pressure loss/drop inside the system is governed by the precharge in the accumulator. When its precharge is low its ability to help top up hydraulic pressure in the system is reduced, so the pressure drops faster, so the pump has to cycle on and off more often.
Geddit? It's all very logical.
Henry
<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Thanks John D, Could you clarify a point for me? Is it the pump that clicks or the accumulator sphere. Pump = loadsamoney, Accumulator sphere = not too bad.
TVM
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>