CurtPalme.com Home Theater Forum

[Curt Palme]

So I've been re-bellowing and fixing up a bunch of spare 9500 LC tubes that I've had kicking around here (check ebay, just listed a low wear R and G tubes for cheap, under 'audiovideotechnician'), and finally found the mystery to the yellowing of the glycol. This may be common knowledge to some, but I can't remember if anyone has posted this.

With tubes that end up with yellowed glycol, what's happened is that the rubber impregnated washers under the fill screws at the top have turned to mush, and the rubber goop actually flows down the threads of the screws, and ends up in the glycol. As the set is used, the glycol moves around, and everything turns yellow. While the fix is pretty easy, you need new glycol and to pop the C element out.

Flush everything out, remove the fill screws, replace them with stainless screws and change those rubber impregnated washers. Parts should be easy to find at a good hardware/screw store, or I've got lots of stock, as I've bought 200 of each. My new policy is to automatically change these on all Marquee LC tubes save for those new old stock ones I've got, as they were built in 2011.

I'll sell a set of 6 screws and washers for $10 incl shipping. 'Round here I have to buy bags of 100, so that's cheaper than buying 100, if anyone is interested.

[Curt Palme]

So I've been re-bellowing and fixing up a bunch of spare 9500 LC tubes that I've had kicking around here (check ebay, just listed a low wear R and G tubes for cheap, under 'audiovideotechnician'), and finally found the mystery to the yellowing of the glycol. This may be common knowledge to some, but I can't remember if anyone has posted this.

With tubes that end up with yellowed glycol, what's happened is that the rubber impregnated washers under the fill screws at the top have turned to mush, and the rubber goop actually flows down the threads of the screws, and ends up in the glycol. As the set is used, the glycol moves around, and everything turns yellow. While the fix is pretty easy, you need new glycol and to pop the C element out.

Flush everything out, remove the fill screws, replace them with stainless screws and change those rubber impregnated washers. Parts should be easy to find at a good hardware/screw store, or I've got lots of stock, as I've bought 200 of each. My new policy is to automatically change these on all Marquee LC tubes save for those new old stock ones I've got, as they were built in 2011.

I'll sell a set of 6 screws and washers for $10 incl shipping. 'Round here I have to buy bags of 100, so that's cheaper than buying 100, if anyone is interested.

[draganm]

[Curt Palme]

I don't know what they are frankly, either the originals or the new ones.

[Curt Palme]

I don't know what they are frankly, either the originals or the new ones.

[the big E]

I may grab a set soon as I need to flush my blue tube(it got gunk in it during December)

[CIR Engineering]

Another thing that turns the glycol yellow is sometimes the fill screws actually rust and the rust gets distributed throughout the coolant. Switching to stainless will stop this problem as well.

craigr