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rossjfox
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What is the purpose of the vacuum lines from the airbox to the oil filler neck?

I switched to Dellortos with pancake filters and no airbox.  Is it ok to just cap the hole in the oil filler neck?

Thanks,

Ross

Brett Gibson JH5 20497
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Ross, the oil filler line is a breather off the the valve covers it should not have a vacumn line going to it.

Brett

Last edited on 09-27-2011 02:12 pm by Brett Gibson JH5 20497

rossjfox
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On my car, oil filler neck "spigott" had a hose going to the carb air filter.  The air pressure inside the air filter should always be at least a slight vacuum.  No?

Are you saying it should just be open to the air?  Or should there be a hose going somewhere else?

Thanks

Jensen Healey
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My '73 oil cap neck has no breather fitting. Do you have a late model car?

Maybe you can tap into the inner plate of the K&N's?

Kurt

rossjfox
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Yes, it is a very late model 75.

I've thought about just what you've suggested.  I can probably do it, but it's surprising how little room there is on the pancake filters when you actually go to try and drill a reasonably sized hole.

But if you don't have one, the question remains what does it do and is it really necessary?  Right now I just capped it.  Mistake?

Ross

Brett Gibson JH5 20497
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Ross, it is just a vent for the valve covers that at times has a bit of vapor coming out thats why it was hooked up to your old air filter box so that what ever came out was sucked thru the carbs and burned off in the engine. In my setup (not for everyone) I tied it into the engine vapor vent near the starter and then ran that down and under the car, my car is not a heavey breather and I dont get hardly any vapor out the hose but if yours breaths alot of vapor you might want to run it thru the carb's. Some cars had the vent and some didnt so plugging it should not be an issue.

Brett

rossjfox
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Now I understand.  Thanks.

Ross



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