This has been in car for over a year but while under the car doing the shift rod and bushing, noticed I have a leak- looks to be from this location, and I cannot get it tighter, and that slot in the plug is horrible design. I am wondering if we can use one of these other plugs with a hex head on it?? And FYI it’s not the stock plunger and spring it’s the Tangerine one.

The only way you can use a different retaining screw is if it's length from the gasket surface to the internal contact surface is precisely the same as the oem piece.

That’s what I figured, so do you know if there is a 914 plug
That has the hex head not a slot? Or do I have a different issue with the fit of the new pressure valve if I can’t get it tighter?

What kind of crush washer are you using?

I have the same issue. Leaking and hard to properly tighten the plug due to having a large slot slot and can't get a good grip.
I believe my crush washer is aluminum. What kind should I be using?
Have tried twice to fix the leak. Would Teflon tape help?

Not sure about Teflon tape but I have used Teflon paste in other leaky threads with good result.

I have the Tangerine relief valve although still not sure if it is intended for drivers rather than track teeners. In any event, I used a bonded aluminum crush washer and have no leaks.

I used to weld a M8 Nut to the bottom of my plugs so I could use a socket instead of a screwdriver.

Have you tried putting a small chisel in the slot and tapping it with a hammer (clockwise) so the plug tightens a bit more?

I like it ...........

It just dawned on me I actually used M10 nuts, not M8.

Going back to the part the Dr. Phil showed, How hard would it really be to measure the original part and match the new part to it. ??

If it was long enough.

Guys there are tools for this you may have to grind it down a little Click to view attachment

Drag link and new crush washer typically so
Vet the problem.

I'm getting set up to do mine..

great idea, i’d have to have someone else do that for me, i don’t currently have access to a welder



So i went ahead and bought a couple of these that have hex head
one was a Porsche part , other came from 356Devotion, but thread specs are the same as ours. i wanted to check and
measure these to compare to stock. as Chris says it better be the same depth on the inside other wise the piston will either not be held up in correct position or this plug will not be able to make it up into place. i think it can be measured with a proper tool. i borrowed one from a friend and i will take some pics of it here and post this today.
now, it turns out the oil leaking along this location was all coming from above this, at my aux oil cooler adapter plate!! this had become loose and i had not checked it or made sure it was secure and torqued correctly on the last filter and oil change SO this weekend i did oil change along with transmission service and found this to be bet loose and now it’s tight and no leaks!!! so it was a false alarm on the plug
leak but that’s fine still need to look at this further

a couple things to consider and a load of infor if you want to read up on this, i found this on Pelican Parts website-

http://forums.pelicanparts.com/911-engine-...lve-thread.html

it looks like on the 911 the factory changes to the hex head plug and changed the depth of it from 12mm to 9mm and changed the spring to increase oil pressure, then later made mods like drilling etc- read the article, i am not getting into that now but also they discuss and show that in the later 944’s they made a part that replace the traditional spring and plunger, and this looks just like the Tangering racing mod that i have installed , so Chis can chime in but i wonder if he got the idea to do this from the 944 or maybe just great engineering minds think alike, as it seems to be a natural or logical thought process and conclusion to come to.
at any rate if you add the thickness of a crush washer @1.5mm, and stayed with a stock spring i think you could use this new plug that has the 9mm depth, but i guess someone here that has an actual pressure gauge could do this and report back? Chris can correct me if i am wrong but the Tangerine mod with the plunger would probably not allow the plug to seal due to the 3mm depth difference, not without modification to the plunger length. i suppose a brave soul could take off 3mm from the bottom of the TR plunger? would this then fit. these are listed part numbers for 911 in the article but appear to be same as ours,
the hex head plug part number ends in 999-064-026-02,
the early plug is 999-064-010-02

Phil

Phil,
my product is 100% my idea and follows a different concept.
The steel sleeve I use eliminates the issue of case wear from years of having the piston/spring move up and down as the engine rpm changes. My sleeve has an o-ring at the top for sealing and a screw near the bottom retains the spring/piston inside. There is no way the precisely machined length can be altered more than a few thousandths to accommodate a different length screw cap.

yes i know ours was from wear, this one on the 944 is similar but for a different reason, not due to wear but to control pressure better, but it is a sleeve with an o-ring at the end and an internal spring-

either way needed to know if you thought we could modify yours
to fit the plug with is 3mm less deep inside the rest is the same, so it would never seat without making the piston shorter. and not necessary anyway at this point not for me . but maybe in future production you could take this into account and make one that would work with the hex head plug. that’s all i was saying. would probably work fine for stock spring.

or one could take and mill 3mm out of the inside of the hex plug to make its internal dimension match up with the 12mm depth of a stock one.

my leak was the adapter for the aux oil cooler we installed when i had my car up there and i didn’t notice it was loose until this current oil change.

here are some pics of the 2 plugs, from different angles, you can see the new style hex
plug is not as deep inside so it’s going to compress a spring by 3mm more, and for the plunger style conversion it would not work you would not get it screwed in, you’d have to use a 3mm thinker crush washer or mill out the inside to accept the length of the Tangerine plunger.
i did verify and measure with this caliper and the new plug depth is 9.13mm and the stock one is 12.53

fyi

A direct comparison with the 914 plug would be more valuable.

the last picture is a 914 plug next to the newer hex plug, direct comparison of the size and depth of one to the other, and the early 911 plug is exactly the same as our 914 plug- the new plug is not, the recess is shallower thus the compare an contrast......
or were you referring to my comparison of the 944 thing? that was just in the same article and i thought it wa intersting they eventually eliminated the standard set up,
my comparison to yours was ment as a complement to you and inventing a solution that looks like porsche engineers also came to a conclusion that was similar, sorry for the confusion.

That is not a 914 plug Phil. The 911 plug is not like the 914 plug.

This is a 914 plug
Click to view attachment

gotcha, thanks for setting me straight!! don’t know why i thought it was,
completely different! it’s an outie not an innie );

well,, maybe it's because 356devotion says it is.