Vacuum Lines
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Vacuum Lines
About two years ago I replaced all my vacuum lines with new ones from a good supporting vendor. Last week I turned on my head lights to find they would barley come up (sort of a nervous twitch). This weekend I tested my relays, actuators and check valve all of which are new within the last year and everything checked out. The only thing I could think of was a loose vacuum line or bad connection. I ended up cutting about 3/8th off the end of every line and the system now works well again. Is this a commend problem with replacement vacuum lines?
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Did you check the vacuum lines before you trimmed them? Sometimes simply testing the individual components doesn't tell you the whole story. You can simply test the component and it's connection by testing from the end of the connected vacuum line.
After I check a component, I hook up the vacuum line and check both together. Next step is connect the next component, test, etc....
After I check a component, I hook up the vacuum line and check both together. Next step is connect the next component, test, etc....
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Did you check the vacuum lines before you trimmed them? Sometimes simply testing the individual components doesn't tell you the whole story. You can simply test the component and it's connection by testing from the end of the connected vacuum line.
After I check a component, I hook up the vacuum line and check both together. Next step is connect the next component, test, etc....
After I check a component, I hook up the vacuum line and check both together. Next step is connect the next component, test, etc....
Team Owner
Joined: Sep 2006
Posts: 31,222
Likes: 4,312
From: Westminster Maryland
Hi Roco,
That same trimming procedure often works on the original hoses too.
I guess it has to do with the hose having a new surface where it seats on the various pipes and nipples.
Fortunately most hoses are long enough so that you can make the cut at each end.
Regards,
Alan
That same trimming procedure often works on the original hoses too.
I guess it has to do with the hose having a new surface where it seats on the various pipes and nipples.
Fortunately most hoses are long enough so that you can make the cut at each end.
Regards,
Alan
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Yea, and I got to do it twice...I only clips the ends to the large lines for the head lights not all that bad. I did the headlight switch only because I was replacing it anyway and was there. The wiper door works great so I did not mess with those. 
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Le Mans Master
Joined: Dec 2003
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From: N J
Apparently it must be somewhat of a common thing.
Only 1 week ago, a friend had this vacuum leak problem in his 71. The shop hooked up a machine that runs smoke through the vac system for detection and it was the same exact problem.
Only 1 week ago, a friend had this vacuum leak problem in his 71. The shop hooked up a machine that runs smoke through the vac system for detection and it was the same exact problem.
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
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From: Vero Beach FL
Race Director
Joined: Jul 2001
Posts: 15,892
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Pushing pressurized smoke through a vacuum system is almost bound to CAUSE leaks.
Melting Slicks
Joined: Nov 2003
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From: St. Charles Mo
CI 5 & 8 Veteran
That obviously depends on how much pressure. hose connections and diaphragms should not be an issue. The dog bone lip seals in the vacum relays would be the only area of concern and that is only temporary.
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
considering the OEM stuff lasted what? 30 years you would think reproduction hose would last a few years, soft hose means it`s the wrong durometer, do I remember correctly this is not the first time we are hearing about this problem? I would think a call to the vendors complaint department is in order or if you post their name maybe they might step up and replace the defective hose....
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
To be honest I thought maybe I did something wrong. I thought maybe the tape that was in the kit was suppose to wrap around the ends (LOL) or something. It is not my intent to "Roast" the vendor if I have a complaint about the product I should have contacted them by phone (sooner than two years) rather than airing it here and give them a chance to make it right.
Thanks for everyone's input and after doing a little research I know what I need to do.
Thanks for everyone's input and after doing a little research I know what I need to do.
Intermediate
Joined: Nov 2005
Posts: 36
Likes: 0
From: Sanford Florida
Most of my vacuum lines are stock and a tight and sealed fit on the connections, your problem decription makes it sound like you need Zip ties to tighten the hose on the connertors, cheaper and easier that the clamps you show above.
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