Oil pressure probs

[flaatr@yahoo.com (Euroroc II)]

Your logic still confuses me... a worn pump means that the clearances have 
widened... which means the pump can no longer build the same amount of 
forward pressure since oil can bleed back... thinner oil, more bleeding 
therefore lower forward pressure. If you use heavier oil and you have low 
pressure then you have a more serious problem like oil passages clogged up...

Think of it this way...
Cold motor in the morning equals thick oil... idles at about 4.5Bar.
Warm motor after a run on the freeway equals thinner oil... idles at about 
1.5Bar.

Thicker oil to start means higher pressures cold and warm, thinner oil to 
start equals lower numbers... I don't run 10w40 in the summer months for 
this very reason. Too thin for hot weather and I have the total overkill 
oil cooler.

If we were to follow your logic then the pressure would go to like 9Bar 
once the motor warms up... not good.

I know this is far from begin scientific, but I know I am right.

Anyone want to share their $0.02 worth of knowledge...

-Raffi


At 01:24 PM 3/10/2003 -0600, ATS - Patrick Bureau wrote:
>all I am saying is that if you have 20w50 in your engine and your oil
>presure light come on, and you swap oil to 10w30 (thinner therefore easier
>to be moved inside engine) and the light goes out, your problem is your oil
>pump being close to shot. this is how I diagnosed my problem and it proved
>me right. the pump bearing was dead once I took it out (1/10" movement
>sideways on the shaft and grinding noise when turned with a drill)
>
>Oil pressure sender guages the amount of oil pressure hitting it (no matter
>what thickness oil is..) if 20w50 (thick) does not pressurise the oil
>properly inside the engine because the pump is unable to push the oil all
>the way up the head, when putting 10w30 (thin) the pump is able (easier) to
>make the oil reach the top of the engine why the light would go out.
>
>I know this is far from beign scientific, but I know I am right, I have
>tested numerous oil pumps this way and they have always proved me correct in
>my thinking and in the need of replacing the pump (versus  a faulty sender)
>
>once I replaced the pump and put 20w50 back in the car the oil did 5 secs on
>oil change and never came back on.
>
>I am not being smuge about this, just stating what my experience is.
>
>
>ATS - Patrick Bureau - txrocco@sbcglobal.net
>
>
>=>-----Original Message-----
>=>From: scirocco-l-admin@scirocco.org
>=>[mailto:scirocco-l-admin@scirocco.org]On Behalf Of Euroroc II
>=>Sent: Monday, March 10, 2003 1:06 PM
>=>To: ATS - Patrick Bureau; John Lagnese; scirocco-l@scirocco.org
>=>Subject: RE: Oil pressure probs
>=>
>=>
>=>Strange logic...  Usually if you have low pressure problems you
>=>run heavier
>=>oil not lighter.
>=>
>=>My take is thinner oil makes lower pressure in worn pump...
>=>
>=>Anyone want to back me up on this?
>=>
>=>-Raffi
>=>
>=>At 05:17 AM 3/10/2003 -0600, ATS - Patrick Bureau wrote:
>=>>no it make perfect sense, it is more difficult for the oil pump
>=>to shuffle
>=>>20w50 than 10w30, thus the oil pressure dropping and the sender
>=>turning on.
>=>>
>=>>ATS - Patrick Bureau - txrocco@sbcglobal.net
>=>>
>=>>
>=>>=>-----Original Message-----
>=>>=>From: Euroroc II [mailto:flaatr@yahoo.com]
>=>>=>Sent: Monday, March 10, 2003 3:53 AM
>=>>=>To: ATS - Patrick Bureau; John Lagnese; scirocco-l@scirocco.org
>=>>=>Subject: RE: Oil pressure probs
>=>>=>
>=>>=>
>=>>=>That doesn't make a lot of sense, 10w30 is thinner than
>=>20w50... isn't it?
>=>>=>
>=>>=>-Raffi
>=>>=>
>=>>=>At 12:08 PM 3/9/2003 -0600, ATS - Patrick Bureau wrote:
>=>>=>>depends on the temperature outside and what oil he is using,
>=>I had this
>=>>=>>issue when running 20w50, but dropped it at 10w30 and it went
>=>>=>away, but it
>=>>=>>was summer time, and this indicated the need for a new oil
>=>pump, did the
>=>>=>>swap for a new one, and 20w50 in the engine and it all go
>=>away. now I am
>=>>=>>unsure what oil for summer time the OEM specs call for on a
>=>>=>Jetta... but the
>=>>=>>diagnosic of it remains the same... could be as simple as a bad
>=>>=>contact on
>=>>=>>the oil pressure sender too.
>=>>=>>
>=>>=>>
>=>>=>>ATS - Patrick Bureau - txrocco@sbcglobal.net
>=>>=>>
>=>>=>>
>=>>=>>=>-----Original Message-----
>=>>=>>=>From: scirocco-l-admin@scirocco.org
>=>>=>>=>[mailto:scirocco-l-admin@scirocco.org]On Behalf Of John Lagnese
>=>>=>>=>Sent: Sunday, March 09, 2003 11:58 AM
>=>>=>>=>To: scirocco-l@scirocco.org
>=>>=>>=>Subject: Oil pressure probs
>=>>=>>=>
>=>>=>>=>
>=>>=>>=>Hi,
>=>>=>>=>One of my teaching colleague's Jetta III 8V is having an oil
>=>>=>>=>pressure prob.
>=>>=>>=>After 1/2 hour on highway there is a few seconds to 20
>=>seconds of oil
>=>>=>>=>pressure light. Oil level is ok. Car is just under 100K.
>=>>=>>=>John
>=>>=>>=>
>=>>=>>=>
>=>>=>>=>_______________________________________________
>=>>=>>=>Scirocco-l mailing list
>=>>=>>=>Scirocco-l@scirocco.org
>=>>=>>=>http://neubayern.net/mailman/listinfo/scirocco-l
>=>>=>>
>=>>=>>
>=>>=>>_______________________________________________
>=>>=>>Scirocco-l mailing list
>=>>=>>Scirocco-l@scirocco.org
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>=>
>=>
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