Oil Pressure - Changing a Piston
 

I found this on an oil starvation thread on the racing section and posted a comment there - but given that people don't read that as much, I am cross posting over here to get people's opinion on this "maintenance" item...

Quote:
Originally Posted by insite View Post
another note on oil starvation:

there is a piston/spring assembly inside the oil pump that varies oil pressure with temperature. when the car is cold, it's designed to increase the pressure to around 100psi. once the car warms up, it backs off to 'normal'.

my car was running about 16-17psi (hot) at idle, which seems low to me. on a hunch, i ordered a new piston & spring. interestingly, the new piston has a chamfered edge whereas the original piston had a sharp edge. this leads me to believe that porsche suspected some binding of the piston assembly in some instances......

at any rate, with the new piston / spring installed, the car is now at 23psi hot. i never logged the oil pressure under load, so i have no idea what (if any) effect it has on pressure at RPM, but i certainly feel a little better. loss of oil pressure at temp is a big concern in the M96. anything that reduces the risk to that end is a win in my book. cost is less than $20 and you can do it in 5 minutes when you change your oil.

FYI, part numbers are:

Piston: 997.107.125.01 ($ 5.00)
Spring: 996.107.127.53 ($10.00)
Gasket: 996.107.123.50 ($ 2.00)

End Quote

So I know this is an old thread, but I was wondering about people's opinion on doing this "upgrade" or refresh on an oil pump piston, spring and gasket. Has anyone tried this? Did it help? If you haven't done it, what is the consensus on doing it? Could it hurt?

Any thoughts would be appreciated.
Fred

Sounds like a great proactive maintenance item. I'll do this while I'm swapping cats. (No, not those cats......)

I swapped those parts out on my 2000. There wasn't really a noticeable difference, but the buy in was under $25, so I replaced them.

Control Piston Update - Tech 1726

Technical Information Update

Engine Concern - Screeching noise from the engine during the warm-up phase.

Symptom: A screeching noise can be heard from the engine at around 2,000 rpm during the engine warm-up phase. In many cases, the noise is an indication that the engine or oil pump has been changed. The noise is caused by the control piston in the oil pump.

If this is diagnosed as being the cause of the noise, this updated control piston must be installed in the oil pump cover. This typically only effects early 2005-2006 models. The fix includes a new control piston and seal. Professional installation and diagnosis is recommended.

I wish I would have known about this before I took my Boxster S to the track. Despite an increased capacity, modified baffles, I'm pretty sure my engine cavitated on a very hot day but well within a normal rpm range. Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well.

Sent from my SAMSUNG-SM-G900A using Tapatalk

I replaced the spring and plunger when this was first posted. I don't think that the spring really loses its "strength" but its easy and cheap, so why not?

I replaced the piston+spring when i did my rebuild ..while you are in there.
From Post above pkp 4911:
"I wish I would have known about this before I took my Boxster S to the track. Despite an increased capacity, modified baffles, I'm pretty sure my engine cavitated on a very hot day but well within a normal rpm range. Oil was also recently changed, however I've also learned that these cars are extremely sensitive to the viscocity as well."
Potentially a terminal situation for your engine !!
Suggest you search "foaming". Known issue in your situation.High detergent oils are the worst. JGDT40 probably the best solution? Also discussed many times on BitoG site. Ford diesel pickups had this issue also.
Baffles/deep sump - some designs are ineffective . Needs a horizontal baffle to prevent oil "climbing" up the walls of the sump ans starving the pickup. The windows in the baffles are another feature to improve. If they don't shut when they should,they are ineffective on longer high g curves.

Appreciate the insights. I'm going to do this when I do the EPS oil lube mod for the IMS since I will be there anyway.

Sent from my SAMSUNG-SM-G900A using Tapatalk