I have a 1990 Celica GT4.
According to the paperwork, it was last charged in 1997. Since then, 
with a previous owner it had a clutch done, which is usually an engine 
out. I'm guessing the the majority of the gas was dumped then.

It was originally an R12 system. It has a black cap (low side I think) 
and a red/brown cap (highside) where the site glass is.
As R12 is now illegal, I've (maybe stupidly) ordered a 1 kilo cannister 
of R49 dropin replacement with an adaptor tube and valve which is 
compatable with the older mineral based compressor oil.

It should take about 700gms/24oz US roughly to fill with R12, will R49 
use less like when a system is converted to R134a (about 80% I've heard) 
or will it use the normal capacity?

I plan to weigh the full cannister. Add about 50% or until the site 
glass shows almost full. Weigh the cannister again to see how much has 
gone in, start the engine to check the sight glass again and topping up.
-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

<snip dodgy DIY aircon work>


> I plan to weigh the full cannister. Add about 50% or until the site
> glass shows almost full. Weigh the cannister again to see how much has
> gone in, start the engine to check the sight glass again and topping up.


How do you know the system is leak free? If it's low (or has no gas) it 
probably has a leak.
How are you going to purge the air from the system first? AC systems must be 
vacuum'd before adding gas.
Have you replaced the receiver/dryer? This should be changed every 3 years 
usually or whenever the system is opened.
How are you going to add the oil the system needs for lubrication?
Do you even know what type of oil it needs?

I would suggest you let an AC engineer look at it as you're likely to end up 
leaking the refrigerant into the atmosphere, or if it's leak free, with the 
moisture in the system freezing and causing blockages. If there is no oil in 
the system the compressor will sieze sooner or later also.

Alan.

"Sleeker GT Phwoar"  wrote in message 
news:MPG.1d2b1271aefdfe1698b071@news.individual.net...

>I have a 1990 Celica GT4.
> According to the paperwork, it was last charged in 1997. Since then,
> with a previous owner it had a clutch done, which is usually an engine
> out. I'm guessing the the majority of the gas was dumped then.
>
> It was originally an R12 system. It has a black cap (low side I think)
> and a red/brown cap (highside) where the site glass is.
> As R12 is now illegal, I've (maybe stupidly) ordered a 1 kilo cannister
> of R49 dropin replacement with an adaptor tube and valve which is
> compatable with the older mineral based compressor oil.
>
> It should take about 700gms/24oz US roughly to fill with R12, will R49
> use less like when a system is converted to R134a (about 80% I've heard)
> or will it use the normal capacity?
>
> I plan to weigh the full cannister. Add about 50% or until the site
> glass shows almost full. Weigh the cannister again to see how much has
> gone in, start the engine to check the sight glass again and topping up.
> -- 
> Carl Robson
> Car PC Build starts again. http://smallr.com/rz
> Homepage: http://www.bouncing-czechs.com


before putting anything in the system needs to be vacuumed down. 
Particularly so if any pipes have been disconnected and any air let in.  The 
sight glass does not show the level, it shows whether anything is moving in 
the system.  If you don't know the amount in there, then you should add gas 
till the pressures (running) are suitable, basically you don't want the 
evaporator as a block of ice, so you add till it is just a little above 
freezing where the gas comes in, the rest will be warmer anyway.

mrcheerful

mrcheerful

In article <AX7we.9237$11.5279@newsfe2-win.ntli.net>, 
alz_deane@nospam.ntlworld.com says...

> <snip dodgy DIY aircon work>
> 
> > I plan to weigh the full cannister. Add about 50% or until the site
> > glass shows almost full. Weigh the cannister again to see how much has
> > gone in, start the engine to check the sight glass again and topping up.
> 
> How do you know the system is leak free? If it's low (or has no gas) it 
> probably has a leak.

I don't know whether it has a leak or not. But as stated previous, after 
the last recorded topup, the clutch has been changed.

As it happens, when attempting to change the thermostat (which requires 
shifting of the compressor) I accidently removed one of the pipe 
mounting bolts rather than compressor bolts.  No gas came out. Last 
owner said it had never worked.


> How are you going to purge the air from the system first? AC systems must be 
> vacuum'd before adding gas.
> Have you replaced the receiver/dryer? This should be changed every 3 years 
> usually or whenever the system is opened.

I haven't because they aren't available from Toyota anymore (other OC 
members have tried to buy them)

> How are you going to add the oil the system needs for lubrication?
> Do you even know what type of oil it needs?


When the AC compressor hose was off a small ammount of green oil (very 
clean looking) leaked from both the pipe and the compressor fitting 
(pipe fitting is at the top of the compressor).


> I would suggest you let an AC engineer look at it as you're likely to end up 
> leaking the refrigerant into the atmosphere, or if it's leak free, with the 
> moisture in the system freezing and causing blockages. If there is no oil in 
> the system the compressor will sieze sooner or later also.


I'm going to take a chance and refill, because I'm sure it was vented 
previously to change the clutch (engine/transmission clutch not 
compressor clutch) and not refilled. AC last refilled at 70k miles, 
clutch changed by backstreet garage at 86k miles.
The system appears to have oil in it, R49 and R314 work with both 
mineral and synthetic oils, R12 needs mineral, R134a requires synthetic. 
if the compressor siezes, they are very cheap to replace due to being a 
common removal item from OC members, converting their cars for 
trackdays.
I agree that freezing may be a problem, but there is no common way round 
it due to non availabilty of R12 system parts from Toyota. for a full 
conversion, the compressor needs to be rebuilt to R134a specs, as well 
as system O rings being replaced. If that is going to be the case, a 
regas as a test is a cheap test. If it breaks it, I learn from my 
mistake and pay about 1/3 of the value of the car (value is much more 
than what I paid for it) in getting the system fully converted, and 
regassed, then regassed more often. 

-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

In article <0Y7we.57882$G8.49247@text.news.blueyonder.co.uk>, nbkm57
@hotmail.com says...

> The 
> sight glass does not show the level,
> 

According to the workshop manual the site glass does show levels

Bubbles or foam, low refrigerant.
Streaking, contaminents in refrigerant.
Occassional bubbles, refrigerant level within normal tolerances.
No bubbles, refrigerant full or refrigerant empty.
-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

In article <0Y7we.57882$G8.49247@text.news.blueyonder.co.uk>, nbkm57
@hotmail.com says...

>  If you don't know the amount in there, then you should add gas 
> till the pressures (running) are suitable, basically you don't want the 
> evaporator as a block of ice, so you add till it is just a little above 
> freezing where the gas comes in, the rest will be warmer anyway.
> 

Thanks. Good advice.
I've pulled lots of useful stuff from the web too, particularly from US 
sites, where R12/Freon is still available, so full conversion isn't as 
popular, but drop ins and blends are starting to appear due to reduction 
in Freon production and an increase in price.
-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

"Sleeker GT Phwoar"  wrote in message 
news:MPG.1d2b26ef87192acd98b074@news.individual.net...

> In article <0Y7we.57882$G8.49247@text.news.blueyonder.co.uk>, nbkm57
> @hotmail.com says...
>>  If you don't know the amount in there, then you should add gas
>> till the pressures (running) are suitable, basically you don't want the
>> evaporator as a block of ice, so you add till it is just a little above
>> freezing where the gas comes in, the rest will be warmer anyway.
>>
> Thanks. Good advice.
> I've pulled lots of useful stuff from the web too, particularly from US
> sites, where R12/Freon is still available, so full conversion isn't as
> popular, but drop ins and blends are starting to appear due to reduction
> in Freon production and an increase in price.
> -- 
> Carl Robson
> Car PC Build starts again. http://smallr.com/rz
> Homepage: http://www.bouncing-czechs.com


if you go to car shows, there are usually places there that will refill r12 
systems with r12

mrcheerful

In article <Eq9we.57927$G8.49391@text.news.blueyonder.co.uk>, nbkm57
@hotmail.com says...

> 
> "Sleeker GT Phwoar"  wrote in message 
> news:MPG.1d2b26ef87192acd98b074@news.individual.net...
> > In article <0Y7we.57882$G8.49247@text.news.blueyonder.co.uk>, nbkm57
> > @hotmail.com says...
> >>  If you don't know the amount in there, then you should add gas
> >> till the pressures (running) are suitable, basically you don't want the
> >> evaporator as a block of ice, so you add till it is just a little above
> >> freezing where the gas comes in, the rest will be warmer anyway.
> >>
> > Thanks. Good advice.
> > I've pulled lots of useful stuff from the web too, particularly from US
> > sites, where R12/Freon is still available, so full conversion isn't as
> > popular, but drop ins and blends are starting to appear due to reduction
> > in Freon production and an increase in price.
> > -- 
> > Carl Robson
> > Car PC Build starts again. http://smallr.com/rz
> > Homepage: http://www.bouncing-czechs.com
> 
> if you go to car shows, there are usually places there that will refill r12 
> systems with r12


Hmm, was planning to visit some american shows.

Of course if was going to be a real cheapskate, I would refill with raw 
propane :) Very cold, but very dangerous.

-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

In news:MPG.1d2b3d9657cc2a9398b07a@news.individual.net,
Sleeker GT Phwoar  decided to enlighten our 
sheltered souls with a rant as follows

> In article <Eq9we.57927$G8.49391@text.news.blueyonder.co.uk>, nbkm57
> @hotmail.com says...
>>
>> "Sleeker GT Phwoar"  wrote in
>> message news:MPG.1d2b26ef87192acd98b074@news.individual.net...
>>> In article <0Y7we.57882$G8.49247@text.news.blueyonder.co.uk>, nbkm57
>>> @hotmail.com says...
>>>>  If you don't know the amount in there, then you should add gas
>>>> till the pressures (running) are suitable, basically you don't
>>>> want the evaporator as a block of ice, so you add till it is just
>>>> a little above freezing where the gas comes in, the rest will be
>>>> warmer anyway.
>>>>
>>> Thanks. Good advice.
>>> I've pulled lots of useful stuff from the web too, particularly
>>> from US sites, where R12/Freon is still available, so full
>>> conversion isn't as popular, but drop ins and blends are starting
>>> to appear due to reduction in Freon production and an increase in
>>> price. --
>>> Carl Robson
>>> Car PC Build starts again. http://smallr.com/rz
>>> Homepage: http://www.bouncing-czechs.com
>>
>> if you go to car shows, there are usually places there that will
>> refill r12 systems with r12
>
> Hmm, was planning to visit some american shows.
>
> Of course if was going to be a real cheapskate, I would refill with
> raw propane :) Very cold, but very dangerous.


You should save the propane and put it in my Rangie instead :-)


-- 
Pete M

Range Rover Vogue SE, Ford Capri (ressurection stalling)
Porsche 911 3.2 (For Sale)

COSOC #5
Scouse Git extraordinaire. Liverpool, Great Britain

In article <42c14897$0$18646$14726298@news.sunsite.dk>, 
pete.murray@blue-nopressedmeat-yonder.co.uk says...


> 
> You should save the propane and put it in my Rangie instead :-)
> 
> 
> 

Now that is Pikey, draining my dodgy Aircon fill to power your car :)
-- 
Carl Robson
Car PC Build starts again. http://smallr.com/rz
Homepage: http://www.bouncing-czechs.com

In news:MPG.1d2b5cfc9ad99bf998b086@news.individual.net,
Sleeker GT Phwoar  decided to enlighten our 
sheltered souls with a rant as follows

> In article <42c14897$0$18646$14726298@news.sunsite.dk>,
> pete.murray@blue-nopressedmeat-yonder.co.uk says...
>
>>
>> You should save the propane and put it in my Rangie instead :-)
>>
>>
>>
> Now that is Pikey, draining my dodgy Aircon fill to power your car :)


*proud*


-- 
Pete M

Range Rover Vogue SE, Ford Capri (ressurection stalling)
Porsche 911 3.2 (For Sale)

COSOC #5
Scouse Git extraordinaire. Liverpool, Great Britain