Aluminium Degas Bottle

I just replaced the degas bottle in my 2003 LS at a very high cost. The original lasted 150k. What on earth causes these things to fail? Why does the Dorman only last 30k? They seem to be made from polyethylene or polypropylene which should last forever.

Apparently the design did not allow for enough flex on the plastic as the system pressurizes and de-pressurizes (cools). I guess you'll just have to do it again at 300K miles.

(Note that 150K miles was the design goal for most of the parts on the LS.)
 
Hey all. Just wanted to keep everyone up to date. I have had aluminum threads made that allow the factory pressure relieves cap to be used with an aluminum bottle. I have also made said bottle and sent it off to another owner on another page for fitment and mounting bracket locations for a final draft of the aluminum bottle. I'll upload pics within a couple weeks so everyone can pick it apart and I can make it as good as possible.
 
Fair enough. I'll keep my eyes out for one. Worst case scenario I get one and test it up to 30 ish psi and if it holds were good to go. Factory cap is 15? I think.
 
Sounds like a good plan. Keep in mind though that even if it passes pressure test... heat and cold cycles could still cause leaks by failure of seal at glass.

Factory cap is rated at 16psi.
 
I believe that industrial suppliers such as Grainger, Fastenal, MSC, and McMaster-Carr carry such items... and usually include manufacturer specs.

zoro.com and radwell.com could be other options too.
 
How about wraping the plasic bottle with carbon fiber sheet to keep it from exspanding and contracting when in use.
 
You'd still have to add a sight glass because the carbon fiber wouldn't allow you to see your fluid level. Which would defeat the purpose because you would essentially be putting all that pressure right where the sight window gets installed.
 
How about wraping the plasic bottle with carbon fiber sheet to keep it from exspanding and contracting when in use.

While that's not a horrible idea... almost every material known to man expands with heat and contracts with cold... even carbon fiber.

Due to the difference in properties of plastic and carbon fiber... over time the carbon fiber would probably de-laminate from the plastic... and the Degas bottle would fail anyway.

Ford/Jag coulda/shoulda built the original out of aluminum... But by the time they had the dies made for the wax moulds... and had the parts sand/ceramic cast... It probably would have added $1000 to the sticker price. I don't think CNC robotic Mig/Tig welding was around then either.

Plus... as conscientious as they were about the weight of the LS... they didn't want to add any unnecessary poundage.
 
man, its times like these I am so glad I moved to a platform that actually has a lot of aftermarket support... one of my planned next couple of purchases.

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I imagine Aron is working on the sight glass fitment and pressure test... as he has time.

Work in this part of the country has been going crazy busy.

I'm actually turning down weekends when someone can cover for me. Speaking personally... I've been doing 60-70 hours a week since Feb of '18.
 
I could have used one a few weeks back having just replaced my "replaced by dealership in 2015 and looks worse than an original" degas bottle just a few weeks ago.
 

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