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Old 11-14-2006, 02:37 AM
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Strife Strife is offline
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Quote:
Originally Posted by Roncallo View Post
I understand the reason for the thermistor and tube and even why they might want to insulate the tube. What I dont understand is why would anyone in there right mind make this tube out of a rubber tube glued to an 8" pice of foam tube and glued again to another rubber tube the same size as the first tube. Why not just sleave the tube in that area with foam or for that mater the whole length of the tube. Im not sure if the foam is closed cell air tight. Maybe its not and maybe they wanted air under the dash to filter in through the foam???. Attached are pictures of the tube showing the disintegrated one and the replacement. From these you can get an idea of how it is constructed. You can see that the foam tube only glues to the last inch of each end of the rubber tubes.

John Roncallo

The only thing that I can think of is that it gets hotter than heck inside the dash (particularly above the radio if you have a modern, 25 watts per 4channel radio without an external amp) and they were trying to keep heat away from the thermistor and the wires leading to it (which can, and do, conduct heat in and of themselves). Solid rubber will conduct and retain heat better than the foam will. You could probably get the same effect with insulating tubing or even tape that's on sale in the winter months in the North at places like Lowes, etc if originality is not important. This is likely what I'll do - $40 for a piece of foam is a bit over the top for me.

I've had one side of my stereo shut down in warm, sunny weather going full -tilt on the highway with the stereo blasting - they almost all have thermal protection in the amps.
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