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impurities build up in Marquee's LC chamber , fungus

post #1 of 10
Thread Starter 
Hello guys,


I'd like to know what other Marquee owners know about this.

I do have a growing amount of impurities build up in my LC chambers.

I've heard that this only happen to Marquee's , since they don't coat the

insides like Barco and Sony used to do.

it already happened once and all chambers were flushed and filled with new

glycol. after 3 months I can see it coming back.

has anyone coated the insides themselfs ??


Thanks


Michael
post #2 of 10
nidi,

I recently refused to purchase a 1996 9500lc for just this reason. Sadly I have no advice to give, perhaps someone else will chime in...
post #3 of 10
I'm pretty sure it comes from the two glycol filler holes. These screwholes are drilled out and its the bare aluminium there that reacts with the glycol.

If you look closely at the holes through the front of the tubes (lens needs to be off), you may see small silver bubbles in the screw holes - thats the aluminium reacting with the glycol. At first I thought it was the iron screws but having replaced these with stainless steel ones, I popped the old iron ones into a glass of old used glycol to see what happened. Other than fungus that appeared (which I suspect was in the old glycol anyway), I have seen no adverse reaction from the old screws. The amount of garbage that comes out of these screwholes over time is incredible, enough to leave dark 'A' shaped streaks on the tube face as well as all the blobs that sit on the bottom of the chamber.

Two solutions for you, lower the level of glycol in the chamber to just below the filler holes so that the glycol can't react with the filler holes (not possible if pj is ceiling mounted), and/or put some silicone in the filler holes before putting the screws back in so that it coats the inside of the filler holes.

The only way sure way to get rid of the impurities is to drain the glycol, dis-assemble the LC housings and remove the C-Elements to get at the chambers, throughly clean the chambers and the tube face with Isopropyl Alcohol (spelling), use distilled water to clean the back of the C-Element. Leave to dry then re-assemble using silicone to seal everything back together again. Not easy but do-able, BUT you run the risk of damaging the bellows in doing this and replacement bellows are now all but impossible to get so this may no longer be a realistic option (difficult NOT to damage bellows when removing the C-Elements as they tend to be very well silconed in - I damaged one out of the three I cleaned). I think some folks tried flushing out the chambers with the bellows/C-Elements in place (i.e. putting cleaning chemicals in through the filler holes) but that will only deal with fungus, it won't address the filler hole problems nor clean the tube face properly.
post #4 of 10
Thread Starter 
Quote:
Originally Posted by Paul Butler View Post

I'm pretty sure it comes from the two glycol filler holes. These screwholes are drilled out and its the bare aluminium there that reacts with the glycol.

If you look closely at the holes through the front of the tubes (lens needs to be off), you may see small silver bubbles in the screw holes - thats the aluminium reacting with the glycol. At first I thought it was the iron screws but having replaced these with stainless steel ones, I popped the old iron ones into a glass of old used glycol to see what happened. Other than fungus that appeared (which I suspect was in the old glycol anyway), I have seen no adverse reaction from the old screws. The amount of garbage that comes out of these screwholes over time is incredible, enough to leave dark 'A' shaped streaks on the tube face as well as all the blobs that sit on the bottom of the chamber.

Two solutions for you, lower the level of glycol in the chamber to just below the filler holes (not possible if pj is ceiling mounted) so that the glycol can't react with the filler holes, and/or put some silicone in the filler holes before putting the screws back in so that it coats the filler holes.

The only way to get rid of the impurities is to drain and remove the bellows, throughly clean the chambers and tube face with Isopropyl Alcohol (spelling) and then re-assemble. Not easy but do-able, BUT replacement bellows are now all but impossible to get so this may no longer be a realistic option (difficult NOT to damge bellows when removing them). I think some folks tried flushing out the chambers with the bellows in place (i.e. putting cleaning chemicals in through the filler holes) but that will only deal with fungus, it won't address the filler hole problems.



Thanks for the tip,

I do have it ceiling mounted. change to LUG tubes a year ago, had all
bellows exchanged. could there be some reaction to the chamber's aluminium
as well, it's hard to believe that such a small area of filler holes surface could react that fast (it's been less than 3 months since the last cleaning)


Michael
post #5 of 10
Quote:
Originally Posted by nidi View Post

Thanks for the tip,

could there be some reaction to the chamber's aluminium
as well, it's hard to believe that such a small area of filler holes surface could react that fast (it's been less than 3 months since the last cleaning)


Michael


Yes, entirely possible. I just didn't see anything in the chamber that looked like it came from the chambers aluminium, everything seemed to stem from the filler holes. Even the blobs had piled up on the bottom of the chamber directly under the filler holes. Certainly the dark streaks came directly from the filler holes.

The old glycol I took out went from clear but slightly yellow to murky with a thick layer of gungy white stuff on the bottom of the glass within about a fortnight, fungus rather than blobs - the change was very fast.

Possibly your chambers weren't properly cleaned and its fungus that you have rather than filler hole issues at the moment? If you can post a photo that would be helpful?

This may be of interest http://curtpalme.com/forum/viewtopic...light=chambers

and this http://curtpalme.com/forum/viewtopic...light=chambers
post #6 of 10
Quote:
Originally Posted by nidi View Post

Thanks for the tip,

I do have it ceiling mounted. change to LUG tubes a year ago, had all
bellows exchanged. could there be some reaction to the chamber's aluminium
as well, Michael

The chamber is Anodized (coated) with a mustard colored coating. The holes are very small and didn't get coated for some reason OR were machined after the chamber was anodized.
As much as I dislike Sony, they did a much better job here with a very large fill screw that has it's internal threads completely coated like the rest of the chamber.
Like Paul said, push a generous amount of RTV into the hole prior to adding fill screws.
post #7 of 10
Quote:
Originally Posted by Paul Butler View Post

I'm pretty sure it comes from the two glycol filler holes. These screwholes are drilled out and its the bare aluminium there that reacts with the glycol.

If you look closely at the holes through the front of the tubes (lens needs to be off), you may see small silver bubbles in the screw holes - thats the aluminium reacting with the glycol. At first I thought it was the iron screws but having replaced these with stainless steel ones, I popped the old iron ones into a glass of old used glycol to see what happened. Other than fungus that appeared (which I suspect was in the old glycol anyway), I have seen no adverse reaction from the old screws. The amount of garbage that comes out of these screwholes over time is incredible, enough to leave dark 'A' shaped streaks on the tube face as well as all the blobs that sit on the bottom of the chamber.

Two solutions for you, lower the level of glycol in the chamber to just below the filler holes so that the glycol can't react with the filler holes (not possible if pj is ceiling mounted), and/or put some silicone in the filler holes before putting the screws back in so that it coats the inside of the filler holes.

The only way sure way to get rid of the impurities is to drain the glycol, dis-assemble the LC housings and remove the C-Elements to get at the chambers, throughly clean the chambers and the tube face with Isopropyl Alcohol (spelling), use distilled water to clean the back of the C-Element. Leave to dry then re-assemble using silicone to seal everything back together again. Not easy but do-able, BUT you run the risk of damaging the bellows in doing this and replacement bellows are now all but impossible to get so this may no longer be a realistic option (difficult NOT to damage bellows when removing the C-Elements as they tend to be very well silconed in - I damaged one out of the three I cleaned). I think some folks tried flushing out the chambers with the bellows/C-Elements in place (i.e. putting cleaning chemicals in through the filler holes) but that will only deal with fungus, it won't address the filler hole problems nor clean the tube face properly.

Paul Your Alive!!!!!! we miss you on curts site, Hope your still not giving up buddy. DId Andy get in touch with you?

Athanasios

PS: sorry i jumped into this thread with no help to offer.
post #8 of 10
Quote:
Originally Posted by draganm View Post

The chamber is Anodized (coated) with a mustard colored coating. The holes are very small and didn't get coated for some reason OR were machined after the chamber was anodized.
As much as I dislike Sony, they did a much better job here with a very large fill screw that has it's internal threads completely coated like the rest of the chamber.
Like Paul said, push a generous amount of RTV into the hole prior to adding fill screws.

has anyone had their LC chambers Anodized? I might give this a try when i move to LC units.

Athanasios
post #9 of 10
Yep, still here my friend, posted some more at the other place. Being 'Alive' is open to debate but still got the pj!

I would imagine that there is some sort of corrosion resistant paint/coating that could be used on the screw holes (personally I wouldn't mess with the larger chamber faces as I personally suspect they are not the issue).

There was mention of nylon screws and also Loctite but I don't favour the loctite option I must admit. (Nylon screws might be a tighter fit in the screw-holes and prevent glycol getting in there?)

One option I've not used is to use PTFE around the screws BUT I don't think this has been tried before and would need to test its resistance to glycol first. (PTFE is white tape that plumbers use on screw-in radiators valves etc to produce a water-tight seal similar to loctite). It would help prevent the glycol getting to the aluminium. Just a thought, I'll maybe dip some PTFE in my glycol test glass and see what happens.
post #10 of 10
Quote:
Originally Posted by Paul Butler View Post

Yep, still here my friend, posted some more at the other place. Being 'Alive' is open to debate but still got the pj!

I would imagine that there is some sort of corrosion resistant paint/coating that could be used on the screw holes (personally I wouldn't mess with the larger chamber faces as I personally suspect they are not the issue).

There was mention of nylon screws and also Loctite but I don't favour the loctite option I must admit. (Nylon screws might be a tighter fit in the screw-holes and prevent glycol getting in there?)

One option I've not used is to use PTFE around the screws BUT I don't think this has been tried before and would need to test its resistance to glycol first. (PTFE is white tape that plumbers use on screw-in radiators valves etc to produce a water-tight seal similar to loctite). It would help prevent the glycol getting to the aluminium. Just a thought, I'll maybe dip some PTFE in my glycol test glass and see what happens.

That be a good idea, i think it will hold up.

Athanasios
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