Vaccum line?????
#1
Three Wheelin'
Thread Starter
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My search lead me to no answered so... My question is, Can soft rubber vaccum lines be substuituted when rigid (hard) vaccum lines are installed? ? Will they colapse? I guess I would have to switch the "T" fittings over too??? Would this work as long as the I.D. is the same?
#4
Three Wheelin'
Thread Starter
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I believe that using rubber lines will cut down in the amount of connections, therefore cutting down the chances of a leak..... I.E. Why have 2 connections just to hook up an FPR? With the rigid line Currently there is a connection at the both ends of the "C" fitting. With rubber there would be Just one, Right on the FPR. Does this make sense?
#5
Nordschleife Master
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Ok, this is something I looked into. If you are talking the soft silicone, small lines you can get in all sorts of colors you have to consider a couple items.
Silicone comes in various grades with adding a filler material being bad. You want to make sure you get 100% pure silicone. You can actually tell if you burn the line with a torch. Pure silicone ash is pretty much pure white. You also want the heavy wall silicone that won't collapse under vacuum - I think something around 22" to 24" of mercury is about the best you will find in standard heavy wall product.
A drawback is that the vacuum system was designed with different hose sizes to match response times. A lot of our system has that small hard black plastic line and you are not going to find silicone that small - so there will be some change, how bad I don't know. The other bad feature is silicone will not stand up to oil forever - the oil will leach through the walls after awhile unless the silicone has an inner liner that is oil resistant and you won't find that in the small tubing. This could be a problem for turbos.
Finally, our system has quite a few vacuum lines that are fairly large, even up to about 11/16" ID so collapse under vacuum takes on more significance and you need to pay attention to the vacuum rating.
So not as simple as just walking down to PepBoys. And this is not a job you want to do more than once.
Silicone comes in various grades with adding a filler material being bad. You want to make sure you get 100% pure silicone. You can actually tell if you burn the line with a torch. Pure silicone ash is pretty much pure white. You also want the heavy wall silicone that won't collapse under vacuum - I think something around 22" to 24" of mercury is about the best you will find in standard heavy wall product.
A drawback is that the vacuum system was designed with different hose sizes to match response times. A lot of our system has that small hard black plastic line and you are not going to find silicone that small - so there will be some change, how bad I don't know. The other bad feature is silicone will not stand up to oil forever - the oil will leach through the walls after awhile unless the silicone has an inner liner that is oil resistant and you won't find that in the small tubing. This could be a problem for turbos.
Finally, our system has quite a few vacuum lines that are fairly large, even up to about 11/16" ID so collapse under vacuum takes on more significance and you need to pay attention to the vacuum rating.
So not as simple as just walking down to PepBoys. And this is not a job you want to do more than once.
#6
Rennlist Member
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Do a search on the lindsey kit(s). They sell a silicon line replacement kit for the small plastic lines and, at least for the turbos, they also sell non-silicon replacements for the large diameter lines.