Vacuum hose question
Thread Starter
Racer
Joined: Nov 2010
Posts: 259
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From: MN
Vacuum hose question
Question about a vacuum hose on my '79. From the intake manifold a vacuum line goes to a filter, to a check valve then splits to a large hose and a smaller hose. The larger hose then T's off again about a foot from the check valve on my car. A larger hose continues on to the air reservoir tank for the headlites and a much smaller hose goes over to the right side and thru the firewall into the cabin. I have looked but cant seem to find any mention of this smaller hose... where it goes and what it does. Anyone have any ideas? Thanks!
Thread Starter
Racer
Joined: Nov 2010
Posts: 259
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From: MN
On my '79 the smaller hose from the check valve goes to the switch to raise the headlights. The hose I am referring to is a smaller hose that T's off the larger one from the check valve. There is no mention of this smaller hose in this diagram http://forums.corvetteforum.com/c3-t...tem-works.html so I am at a loss
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Thread Starter
Racer
Joined: Nov 2010
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From: MN
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Here is the hose going through the fire wall, you have to check from here back to make sure there are no leaks.
Team Owner
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Adding a vacuum pump to a system that has vacuum leaks will NOT solve operational problems. If you have low vacuum, due to a radical cam and engine build...but the vacuum system is leak-free and still doesn't work...then a vacuum pump might be a reasonable solution.
Otherwise, find the leaks and/or defective components and fix them.
Otherwise, find the leaks and/or defective components and fix them.
Thread Starter
Racer
Joined: Nov 2010
Posts: 259
Likes: 70
From: MN
Adding a vacuum pump to a system that has vacuum leaks will NOT solve operational problems. If you have low vacuum, due to a radical cam and engine build...but the vacuum system is leak-free and still doesn't work...then a vacuum pump might be a reasonable solution.
Otherwise, find the leaks and/or defective components and fix them.
Otherwise, find the leaks and/or defective components and fix them.
Didn’t mean to imply I was going to install a vacuum pump to replace or supplement the system. What I was curious about is if I was to draw a vacuum on the smaller line with a mity vac hand pump should the line hold a vacuum meaning if it doesn’t there must be a leak.
