NEED HELP QUICK on pressure relief valve...
#1
Rennlist Member
Thread Starter
NEED HELP QUICK on pressure relief valve...
so I just made the mistake of taking out the pressure relief valve (i think) instead of the drain valve while changing the oil. I was thought I could just get it back together and then I found this little part (the one I am pointing to in the picture) and I am not sure where it goes. help please. Thanks guys..
#2
Rennlist Member
It is a spacer that goes over the gold tube you show entering the spring and under the spring. It nests on top of the flange on the gold tube. Then the whole assembly goes spacer side down into the threaded plug.
#3
Rennlist Member
Thread Starter
Cupcar, thanks for the quick reply. so this picture is how I imagine it going back into the car. When I was finishing taking out the oil filer the "cap" fell out of the hole. So is this right?
#6
Rennlist Member
Thread Starter
got it guys. thanks a ton!!
Trending Topics
#9
Rennlist Member
It really doesn't matter where the ring goes, over the tube onto the flange or under the flange of the tube, Porsche has illustrations that show it in either place.
#10
Rennlist Member
Thread Starter
Thanks again guys, it is amazing how knowledgable everyone is and how willing everyone is to help those of us that are far from mechanically inclined but like to try a few things every now and then. So how exactly does the valve work and what does it do?
#11
Rennlist Member
Its a "pressure relief valve" and the design (piston diameter and spring rate) sets the pressure that it opens at. In this case 5.3 bar or 78 psi. (A)
There is "safety valve" that opens at 9 bar or 132 psi. (B)
Notice how they have the orientation of items 4 and 5 different in this service manual pic than the one previously posted.
There is "safety valve" that opens at 9 bar or 132 psi. (B)
Notice how they have the orientation of items 4 and 5 different in this service manual pic than the one previously posted.
#12
i had a cow once on my seventy. took it to my old mechanic and he told me my 70 was a euro...and the measurement were in bars..not in like the american version...
duh.. felt like homer simpson
Lemon
duh.. felt like homer simpson
Lemon
#13
Rennlist Member
The oil gallery resistance stays the same.
As engine RPM increase, the positive displacement oil pump increases in speed along with RPM and thus increases oil flow delivery to the oil galleries.
When flow is enough to raise pressure to push the "pressure relief" valve piston off the orifice it plugs, flow is diverted back to the intake side of the pump in late engines (early engines forgot year, pre '72?, divert to sump), thus decreasing flow and thereby pressure is relatively constant over a range of RPM as the piston is pushed further off the orifice as flow increses.
The "safety valve" is a hail mary save if the engine is over revved when cold to prevent too much oil pressure and diverts oil directly back to the engine sump.