fuel distributer o-rings and extra ??s

[porsche.racer]

Hi all,

I am currently working on a 3.0sc engine and have diagnosed the fuel problem to the distributer (I hope). I am familiar with 924Turbo fuel distributer but have never played with a 911 version. I assume they are the same but with 6 lines v. 4 lines out to injectors.

My questions are: (the car sat for up to 2years)

1. Can I buy the exact o-rings for a rebuild? Are they available?

2. I am not 100% sure what to call the center 'piston' (the piston that slides to control fuel based on the air meter). But should this piston not slide freely, similarly to the 924T. ---- I coul not get the piston to slide (it is in the 'in' position - meaning it is in the distributer all they way) I could not pull it out forcibly. So, I split the distributer ( I have done this 3 or 4 times successfully on 924T). Once apart the piston was removed with a little effort, but easy enough. I cleaned lubed and prepared to put back together. However, when the halves are not snugged together tightly the piston moves freely, but as soon as I tighten the halve together the piston is stuck again, as if it was being pinched or squeezed. But, I cannot understand by what. The only explanation I can devise is that the six liitle o-rings shift during install and some how put pressure on the small eye-slots for the fuel flow? Ok, so to recap 1. should the piston be free? (yes, right). 2. Can I buy replacement o-rings (all of them would be great). Or does anybody have a good distributer for sale?

Thanks

MIke

[porsche.racer]

can anyone confirm this is the correct part or the exact model years that this part fits under

0.438.100.077

thanks