Whats This Port ?

[AusPorscheGuy]

Hi Guys

I've been chasing vacuum leaks on my 74 Porsche 911 on another thread due to starting issues. I ran a smoke test today hooking up the tester to the vacuum line that goes from the throttle body to the decel valve and found smoke coming out of the side of the throttle body from the area highlighted in the picture. I think its the shaft that the butterfly rotates on but I have no idea whether it should be sealed or whether you'd expect to leak in a vacuum test. I can't seem to find a reference to it on the forum. Any ideas ?

Cheers Daren

[twistoffat]

Think its for the control pressure regulator

[AusPorscheGuy]

OK I think I answered my own question.. Its the throttle lever shaft. The shaft goes through a bearing. Behind the bearing is a rubber o ring that sits in some kind of metal sleeve . Part of the sleeve is broken meaning that the o ring has nothing to compress against, since there is a space between the o ring and the bearing where the sleeve piece is broken. Hence the leak and the smoke coming out. I've tried to fix it by building up the space with sealant. I'll let you know how I go.

Daren

[E Sully]

It seems as though you are missing your Throttle Control Valve, part #911 110 916 00. The purpose is to vary the mixture at idle, cruising mid throttle mixture, and full throttle. It was eliminated in late CIS models where they used a vacuum controlled WUR.

[AusPorscheGuy]

Thanks Ed

Yep I have a 033 vacuum controlled WUR. I guess the question I now have is whether removing the throttle Control Valve and not plugging the opening would result in a vacuum leak ?

Daren

[E Sully]

You could also consider getting a throttle body from a later 2.7 that does not use the throttle valve.
I am sending a PM with one for sale from another Pelican.