Colored coolant in Sony CRT projector?
Michael
I am replacing the coolant in a Sony VPH-1000QM video projector (made in
1993). The coolant was clouding the glass of the tube surface in patches
(especially on the blue tube). These tubes are a bit unusual, as there is a
flat piece of glass glued to the front of the tube with Silastic (or
similar), with a small gap (about 1/4") which is filled with cooling fluid,
and only a couple of tiny holes to fill / drain the fluid. I was able to
fairly easily take the glass off, and clean up the mess, though.
My question is this: What do I do about the colored coolant that is in the
red tube? I bought a can of "Heat Transfer Fluid" (RITE OFF brand, from MCM
electronics) that is intended for PTV repairs. This is not colored - can it
be colored somehow?
The blue tube has clear fluid, and the fluid in the green tube (strangely)
has a very slight BLUE tint to it, but is hardly noticeable. The fluid in
the red tube has a fairly PINK color.
Any ideas would be appreciated!
Regards,
Michael
Heath Young
you need to register, but chances are if you search the archives, you will find
all the info you ever need.
This is normal for CRT projector tubes.
>The coolant was clouding the glass of the tube surface in patches]
Fungus growth no doubt - a pain in the @$$ isn't it.
>The blue tube has clear fluid
Normal
>Fluid in the green tube (strangely) has a very slight BLUE tint to it,
Used for colour correction - could use clear but colour balance would be
*slightly* off.
>The fluid in the red tube has a fairly PINK color.
Yes - important - have you tried food colouring? Art suppliers? Etc - some
people fit colour filters from photographic/theatre suppliers as well.
Cheers
Heath Young
Michael
information.
As it turns out, I will reuse the existing coolant from the red and green
tubes, since I managed to save almost all of it. I managed to suck the
coolant out through one of the tiny fill holes, using a syringe with needle
and some very fine plastic "tube" (actually, just the insulation off some
electrical wire). I needed to do this before I used a knife to cut the
"Silastic" that was used to glue the glass cover plate in place, since I
wanted to save the coolant. I might run it through some filter paper, even
though it seems perfectly clean. I didn't save the coolant in the blue tube,
since it was not colored, and I have some replacement coolant.
Now I just have to glue the glass back on (with non-corrosive Silastic), and
refill the coolant.
The "clouding" on all 3 tubes was weird - it looked and felt like the glass
was frosted, and I needed a razor blade to get it off. It seems strange that
they can't put anti-fungal substances in the coolant to stop this kind of
thing. Hopefully I'll get a few more years out of the tubes before they are
dead, or I have to repeat the process again!
Bill Jr
assemblies.
These coolant tanks are made of cast aluminum and as such they react with
the ethylene glycol.
This is what is causing the cloudiness on the glass surfaces.
Now the interesting part... if you don't seal the exposed, corroded pits in
the aluminum then you will have this problem again soon.
A good high temp flat black spray paint does the job for me.
Clean the coolant tank well, mask the lens and paint away. I usually allow
24 hours for drying time.
It is also good to allow 24 hours curing time for the "Silastic" before
refilling with new coolant (or filtered, used coolant).
Good Luck,
Bill Jr
"Michael" <m_nobl...@tpg.com.au> wrote in message
news:3d3e...@dnews.tpgi.com.au...
Bill Jr
As long as you don't see any grey pits then you might be ok to forget about
the paint.
And yes, I'm very familiar with that series projector.
I do see them with pits and you are correct, very little coolant.
I think the VPH 1040,1240,1270 holds a bit more coolant than the 1000.
Looks like you are no track to a successful repair.
Good Luck
Bill Jr
"Michael" <m_nobl...@tpg.com.au> wrote in message
news:3d3f...@dnews.tpgi.com.au...
> Thanks for the advice. There is no coolant "tank" as such - it is trapped
> between the CRT face and a glass window. There is less than 2 ounces of
> coolant in each tube. However, the housing is made of black anodized (??)
> aluminum, and I guess this is causing the problem (even though it doesn't
> look pitted). The "frosting" on the glass seemed too hard to be a fungus.
>
> I've attached a drawing (I hope it comes out OK) that shows the
arrangement.
> As you can see, there is very little area to paint, and much of it is
hidden
> by the lip of aluminum (and can't really be painted). My initial thought
was
> to fill the area labeled "AAAA" on the diagram with Silastic (as well as
> covering the rest of the exposed aluminum with a film of Silastic), but
then
> I realized that this would insulate the coolant from the housing,
> restricting the cooling effect.
>
> What do you think?
>
>
>
Bill Jr
"Looks like you're on track to a successful repair."
Bill Jr
"Bill Jr" <bi...@nospam.usa2net.net> wrote in message
news:Tj%%8.695$s8.2...@twister.tampabay.rr.com...
Alan Harriman
wrote:
>I believe you might be mistaken about the fungus in those Sony coolant
>assemblies.
>These coolant tanks are made of cast aluminum and as such they react with
>the ethylene glycol.
>This is what is causing the cloudiness on the glass surfaces.
>Now the interesting part... if you don't seal the exposed, corroded pits in
>the aluminum then you will have this problem again soon.
>A good high temp flat black spray paint does the job for me.
>Clean the coolant tank well, mask the lens and paint away. I usually allow
>24 hours for drying time.
>It is also good to allow 24 hours curing time for the "Silastic" before
>refilling with new coolant (or filtered, used coolant).
>Good Luck,
>Bill Jr
Hi Bill,
I'm familiar with the pitting you're referring to. In fact, we're
doing a Sony coolant job now. (KPR-41DS2) Couldn't the pits be filled
in with RTV compound, or as Clarke Electronics recommends, SHINITSU
SEALANT?
Thanks,
Alan Harriman
Michael Noble
week once the Silastic is set and I've put all the bits back together.
Thanks again.
"Bill Jr" <bi...@nospam.usa2net.net> wrote in message:
Bill Jr
Yes, this is also an acceptible method that I have used in the past when
there were only 1 or 2 pits found.
You will probably also notice an extra piece of glass inside those comsumer
models that aren't present in the comercial versions.
Don't leave them out. They are a PITA to work with.
Good Luck
Bill Jr
"Alan Harriman" <vt...@usol.com> wrote in message
news:ckf1kugqcjo5cts1q...@4ax.com...
Michael Noble
now! Thanks to all who responded.
michae...@hotmail.com (Michael Noble) wrote in message news:<78eeb98a.02072...@posting.google.com>...
Bill Jr
Bill Jr
"Michael Noble" <michae...@hotmail.com> wrote in message
news:78eeb98a.0208...@posting.google.com...
Heath Young
Cheers
Heath Young