Is the oil pressure relief valve in the oil pump? - AudiWorld Forums


Is the oil pressure relief valve in the oil pump?

Reply
 
 
 
Thread Tools Search this Thread
Old 06-26-2004, 01:08 PM   #1
AudiWorld Super User
Thread Starter
 
Join Date: Jan 2003
Posts: 9,298
Default

Is the oil pressure relief valve in the oil pump?
moribundman is offline   Reply With Quote
Old 06-26-2004, 01:34 PM   #2
AudiWorld Super User
Thread Starter
 
Join Date: Jan 2003
Posts: 9,298
Default UrS4...

The oil pressure relief valve should not allow excessive oil pressure, whether the filter bypass valve is open or closed, or am I mistaken?
moribundman is offline   Reply With Quote
Old 06-26-2004, 09:22 PM   #3
eep
AudiWorld Member
 
Join Date: Apr 2004
Posts: 253
Default Re: Is the oil pressure relief valve in the oil pump?

Nope ... it's part of the oil pickup assembly on the AFC engines.<ul><li><a href="http://www.12v.org/engine/index.php?section=fe">http://www.12v.org/engine/index.php?section=fe</a</li></ul>
eep is offline   Reply With Quote
Old 06-26-2004, 10:32 PM   #4
AudiWorld Super User
Thread Starter
 
Join Date: Jan 2003
Posts: 9,298
Default

I should have known you had some pertinent info on your site. Thanks!
moribundman is offline   Reply With Quote
Old 06-27-2004, 06:20 AM   #5
VAP
AudiWorld Super User
 
Join Date: Mar 2000
Posts: 13,991
Default there's at least one other known pressure-relief valve...

<center><img src="http://pictureposter.audiworld.com/711/prv.jpg"></center><p>used in the AAH/AFC engines in the cylinder heads that regulates oil pressure in the lifter oil gallies in each cylinder head.

And there's another one under the valley pan tho I can't tell from the diagram if either are addressed via it's circulation layout.

One things clear... these engines have a lot of in-line oil pressure reliefs going on. Way more than any other engine I'm personally aware of. Great when they work... a potential nightmare if/when any one fails. And everything mechanical will fail.
VAP is offline   Reply With Quote
Old 06-27-2004, 10:17 AM   #6
AudiWorld Super User
Thread Starter
 
Join Date: Jan 2003
Posts: 9,298
Default That's a little scary

I've had the occasional low oil pressure on previous cars, but I've never had too high oil pressure. I suspect our oil pressure idiot light won't come on if the pressure is too high...
moribundman is offline   Reply With Quote
Old 06-27-2004, 04:47 PM   #7
eep
AudiWorld Member
 
Join Date: Apr 2004
Posts: 253
Default Re: there's at least one other known pressure-relief valve...

Good call! I never think of the two valves in the head. You can't tell from the picture, but the hex part of the valve is connected to the rest by an extremely thin bit of metal - so thin, in fact, that you're just as likely to twist the head off and have a nice smooth hole in your head than remove the valve. Nice. The valve on 30v engines has a Torx head embedded in the valve body instead, much nicer.

So: oil pressure relief valves:
- 16 bar (232 psi) in oil pickup assembly
- 11 bar (160 psi) safety valve, only opens at high RPM and cold engine temp; AFC only
- pressure relief valve, *cough* in the oil pump
- now in the engine; there are the pressure valves Mance mentioned, one on each head. Those control top-end oil pressure.
- there are two oil check valves in the steadying chamber (under the valley pan), but those don't really do much in terms of pressure control; they just keep oil in the lifters when you shut the engine off.

There's also some pressure control done by the head gasket - each one has a finely-tuned obstruction to oil flow that maintains oil pressure in the engine block when the oil pressure relief valves are open.
eep is offline   Reply With Quote
Old 06-29-2004, 06:23 PM   #8
eep
AudiWorld Member
 
Join Date: Apr 2004
Posts: 253
Default The poop on engine lubrication

If anyone is still reading this thread (and cares), I've put a bit more detailed information on the engine lubrication setup at 12v.org:<ul><li><a href="http://www.12v.org/engine/index.php?section=hw&amp;sm=oil">http://www.12v.org/engine/index.php?section=hw&amp;sm=oil</a</li></ul>
eep is offline   Reply With Quote
Old 07-01-2013, 10:41 AM   #9
AudiWorld Newcomer
 
Join Date: Jul 2013
Posts: 2
Default

OK so im a little confused...I have an AHA (99 2.8 A6) do i have a relief valve?

here is my problem: when the engine is cold the oil pressure is perfect through the RPM range ( checked with mechanical gauge) but when the engine gets to normal operating temp the oil pressure drops at 1500-2000 rpm then shoots back to normal. It has a new oil pump and full Syn oil in it, and a OEM Mann filter.
lostroot1 is offline   Reply With Quote
Old 07-01-2013, 02:51 PM   #10
AudiWorld Super User
 
CRAZY_RUSSIAN's Avatar
 
Join Date: Oct 2008
Location: Reno, NV
Posts: 2,716
Default

run some seafoam in your oil for about 200 miles, about 1/3 of a can
CRAZY_RUSSIAN is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
:: ECS Tuning :: NEW!! B8 A4 2.0T ECS Baffled Oil Catch Can ECS Tuning-Audi A4 (B8 Platform) Discussion 14 12-23-2016 03:46 AM
1995, 90 Quattro - low oil pressure light/buzz at 2,100 rpms + hardipk5 Audi 90 / 80 / Coupe quattro / Cabriolet 17 11-24-2015 03:42 AM
2004 Allroad Clarkbowman Audi allroad 3 09-10-2015 05:46 AM
New member with a few questions scottnybottny A8 / S8 (D3 Platform) Discussion 0 09-05-2015 10:52 PM
:: ECS Tuning :: NEW!! B8 A5 2.0T ECS Baffled Oil Catch Can ECS Tuning-Audi Audi A5 / S5 / RS5 Coupe & Cabrio (B8) 0 09-01-2015 08:27 AM


Tags
1994, 2005, a4, a6, aah, afc, audi, check, oil, pan, pressure, regulator, relief, urs4, valley, valve, valves

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -8. The time now is 10:45 PM.


 
  • Ask a Question
    Get answers from community experts
What's your question?
Send