Having a head pressure to prevent cavitation - that makes sense. So the
restrictor is necessary to prevent it.

John

On 7/11/2012 11:43 AM, Pat wrote:
>>From Googling around it seems that high flow rates cause cavitation in the
> pump which makes the noise.
> I guess the pump likes to see some head pressure to run quietly.
> BTW, this isn't a Vanagon specific problem; I got this info from a Maxima
> board.
> A link to a hose repair shop says this is a common problem on European and
> Asian makes.
> But, a Chrysler minivan forum also brings up the issue, so I would say it's
> almost universal.
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> JRodgers
> Sent: Tuesday, July 10, 2012 8:08 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: power steering
>
> Larry, I haven't a clue, myself, as to why that restrictor is needed.
> But in my own experience, the restrictor  must be there. I had to
> replace that short pressure hose with the restrictor. I did it with a
> hose that had no restrictor. I went through 5 pumps thinking they were
> all bad, given the racket they were making, and three of those pumps
> were brand new remanufactrure pumps. I sent them all back as bad pumps.
> I was totally embarassed when I learned of the fix. Dennis Haynes or
> Scott Daniels - can't remember which - told me about  having to have the
> restrictor else I would have lots of noise like a bad pump. Turned out
> to be true. Lots of noise. Replaced the non-restrictor hose with one
> with a restrictor, noise was gone. Just my experience.
>
> John
>
> On 7/10/2012 6:48 PM, Larry Alofs wrote:
>> What is the purpose of the restrictor anyway???
>>
>> Larry A.
>
>
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