Ghost944

Dan said his car (89 right?) has an oil check valve in this location (see pic) which keeps pressure in the little oil channel in the cam box.. he seemed a bit confused when he saw that there was not one in my 86, but assumed it was different cuz his in an 89.
should there be one here in my '86?? i wouldnt normally worry except this is the general area my leak is coming from.

xsboost90

actually i talked to andy -nine44- and he said they all had them but only the later cars had the screw to hold them i guess. You may need to buy one and press-hammer- it into that hole. I would call Beechmont and talk to someone and see if they have a oil checkvalve for the head. That could be the reason why your top end ticks every time you start it...it also keeps the top end from over pressurizing and * blowing out cambox seals!

Ghost944

goddammit

o and for reference, whats it look like? damn i hope i can get it tommorow, not at all likely! so if they dont have one, which cars and years have this same head? or which ones will fit?

KuHL 951

I saw a write-up in the shop manuals about removing these on the early cars. You actually need to drill and tap it to extract it with a puller. They usually don't go bad but when they do the lifters chatter like crazy at start-up.

TheRealLefty

Hmmmm. Tell me more. My 89 Turbo with 75K on the odo, runs like a top, but I have noticed that when I park the car on an incline nose-uphill, even if just for few minutes, there is a brief second of valve clatter at start-up, none thereafter, and never when parked level or downhill.

Related?

xsboost90

i dont think ghost's car even has one...looks like its just a hole there.

alordofchaos

I'm dense... Looking at Dan's avatar ( testarossa), I just now got it...

XSBoost = Excess Boost.

D'Oh!

Ghost944

i dont get it... where the hell did mine go?
(meant to post this pic in the first post.)

Ghost944

DAMN! i just called beechmont porsche and the parts lady says there isnt one in the entire country, and i cant find it from any of the online suppliers!!!! what do i do? it ran without it for some time obviously, is there any danger in runnin without it?

mein51

Don't let that stop you. I've been told that before *cough*zims*cough* but one call to Paragon had me what I needed the next day. Try calling around on your own. If you can't find what you need, some parts places are really good about getting parts from other sources.

xsboost90

sometimes machine shops will take those out and i guess its up to the installer to put it back in- looks like someone forgot to do that.

xsboost90

just called 944online and they said they can get a check valve...its only $345 and they can get it tomorrow!

Oddjob

According to PET, there are two versions of the check valve/pressure relief depending on which head/year.

One is a plug with a ball and spring:
951 104 229 00
928 104 129 00
N025 669 2

The other looks like a pressure relief valve assembly with screw and seals:
944 107 239 01
N 014 740 2
999 123 032 30
999 707 078 40

One type is not listed to superceed the other, so both types appear to still be available.

Little unclear from the part listing, which head the different parts are to be used with. Looks like the separation is between the n/a -06 (MY 87 and older) and the -08 (MY '88 and newer) heads. And with the Turbos its the -01 (M51 Standard Turbo) and the -02 (M52 Turbo S) heads.

I know the heads I have had off an 88TS and 89T motor had the ball and spring check valve, but my 87T also had the same.

Hopefully you can get clarification on which are needed for your year head, or if they are interchangeable.

xsboost90

yeah my 89 has the set screw , this one presses in... Anyone have one laying around?

Ghost944

i hope that 345$ is for yours dan. mine would be much simpler and i hope it cheaper, i dont have 345$!!!!!

but the question still stands, can i run without it for a little while?