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porschefile2010
Hi again. Help! I have noticed oil or oil condensate gathering at the front left of the engine on the tin and vacuum lines. Also the car isn't idling perfectly and the plugs are a bit black except for the electrode which looks the right colour. I also notice today a bit of smoke in off throttle situations coasting down hill, but not under power??
So I went hunting the forums and thought maybe the vacuum lines were loose or split.
The car appears to have had a new exhaust setup put in and I can't find any trace of a charcoal filter or emmissions pump or whatever they used to have so there have been changes.
But to the point.
There is a vacuum hose coming out of the tinware front left of the engine right next to #2 plug. In my car it is poked out through a small hole in the rear firewall??? and not plugged in to anything.
Can anyone tell me where this should go? I figured it might be meant to go to the charcoal filter but if that is removed where then.
It also looks like there used to be a vacuum line terminal at the narrow end of the air cleaner which had something screwed or bolted to it and this has been closed off?
One other mod has been the points taken out of the distributor and an electronic unit substituted if that has any bearing on it.
Thanks in advance.
Richard
TheCabinetmaker
That is not a vacuum hose, but a head vent hose. The 75 did not come with vented heads. Someone has switched engines, or one or both heads. If both, there is another next to the#3 plug(opposite corner). Check the serial# of the engine. Its located in front of the oil filler. Another possibility is that the heads have been drilled for the vents. Common practice, ive done it. The hoses should be ran back to the air cleaner. That is most likely your smoke screen. Oil is running out of the hose onto the exhaust.
JeffBowlsby
These may help. From here: http://bowlsby.net/914/Classic/TechNotebook.htm

porschefile2010
Thanks guys.
The engine is defiantely original. GC001689 and matches the car 4752906002. So I will check off the diagram today. The oil is all over the end of the hose at the #2 plug end but dry and dusty at the unconnected end.
porschefile2010
Sorry. So in that diagram, where the long hose shown starts at "nipple type13" and heads off to the filter. Where is that coming from? It's not the #2 cylinder as that is shown separately?
TheCabinetmaker
The one from # 2 and "3 meet at a collection box (anti flashback valve) and go on to the air filter via a third hose. In the diagram, hose 5 and 6 go to the valve and 4 goes from there to the air cleaner.
porschefile2010
Yes, thanks - got that one ok. But Hose 1 goes into a filter at the bottom and comes from the very top left of the diagram. What is that that it is coming from. That's the one in my car that goes nowhere. I'm ok with the ones going to the flashback, it's just this one that comes out of the tinware in the front left car near the fan/alternator. Appreciate your help. Thanks
JeffBowlsby
Hose #1 is just an air supply tap off the fan plenum (nipple is on the tin)...it routes supply air to the charcoal filter, which a 1975 car would also have had originally in the engine bay. If you have no charcoal filter you could simply cap that nipple off. Should be no oil there, so if you do have oil find the source of it.
porschefile2010
Hi Jeff. That's the answer I needed. Thanks very much. I will blank it off tonight.
malcolm2
QUOTE(Jeff Bowlsby @ Oct 30 2011, 02:17 PM) *

Hose #1 is just an air supply tap off the fan plenum (nipple is on the tin)...it routes supply air to the charcoal filter, which a 1975 car would also have had originally in the engine bay. If you have no charcoal filter you could simply cap that nipple off. Should be no oil there, so if you do have oil find the source of it.


I just posted a similar question.....I have a 75 with no charcoal filter, and no fan housing fitting. My engine was dead when I got it, so I don't know if I need. Sounds like I don't. But it also sounds like it should have had the charcoal.

Thoughts?
JeffBowlsby
The air supply nipple on the 1975-76 cars should be on the passenger side of the fan housing,
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