300M A/C overhaul

It's about 6 months since our '02 300M's A/C quit with a hissing sound
and a sweet smell in the cabin. I bought a replacement evaporator,
heater core and receiver/drier a while back but haven't yet installed them.

I've been reading the service manual and have questions:

1. A lot has to be removed to get at the evaporator and heater core. Is
it really so much of a hassle that I ought to try to find somebody who
will do the job for me?

2. If it *is* something I ought to be able to do myself:

(a) I can't figure out whether I have to remove the steering wheel or
not. The Chilton manual (for LH-series vehicles up to 2001) says to
remove the steering wheel first, but the Chrysler manual seems to allow
for removing the steering column with the wheel still in place.

(b) I've been reading that the refrigerant oil is highly hygroscopic
(absorbs moisture, even from the air), so what about the oil still in
the system? Will that have absorbed moisture through the leak that
allowed the refrigerant to escape, so that it will all need to be
drained and replaced?

Anything I might not have thought of?

Perce

On Thu, 07 Apr 2011 17:58:59 -0400, "Percival P. Cassidy"
> wrote:

>It's about 6 months since our '02 300M's A/C quit with a hissing sound
>and a sweet smell in the cabin. I bought a replacement evaporator,
>heater core and receiver/drier a while back but haven't yet installed them.
>
>I've been reading the service manual and have questions:
>
>1. A lot has to be removed to get at the evaporator and heater core. Is
>it really so much of a hassle that I ought to try to find somebody who
>will do the job for me?
>

If you don't mind spending the money it's probably worth it. the
first time you do one of these kinds of jobs is a real learning
experience.

>2. If it *is* something I ought to be able to do myself:
>
>(a) I can't figure out whether I have to remove the steering wheel or
>not. The Chilton manual (for LH-series vehicles up to 2001) says to
>remove the steering wheel first, but the Chrysler manual seems to allow
>for removing the steering column with the wheel still in place.
>

Unless its just for convenience in clearance I don't see why you'd
need to remove the wheel if you are taking the whole column out. If
you do take it out make sure you don't let it rotate or it will mess
up the clock spring wire I've been told on many cars.

>(b) I've been reading that the refrigerant oil is highly hygroscopic
>(absorbs moisture, even from the air), so what about the oil still in
>the system? Will that have absorbed moisture through the leak that
>allowed the refrigerant to escape, so that it will all need to be
>drained and replaced?
>

If you tape up the ends when you disconnect them you should be fine.
Small amounts of water will be pulled out when the system if put back
together and a vacuum is pulled on it to evacuate all the air and
water vapor before putting freon back in.

>Anything I might not have thought of?
>
>Perce

On 04/07/11 07:16 pm, Ashton Crusher wrote:

>> It's about 6 months since our '02 300M's A/C quit with a hissing sound
>> and a sweet smell in the cabin. I bought a replacement evaporator,
>> heater core and receiver/drier a while back but haven't yet installed them.
>>
>> I've been reading the service manual and have questions:
>>
>> 1. A lot has to be removed to get at the evaporator and heater core. Is
>> it really so much of a hassle that I ought to try to find somebody who
>> will do the job for me?

> If you don't mind spending the money it's probably worth it. the
> first time you do one of these kinds of jobs is a real learning
> experience.

Still thinking about it.

>> 2. If it *is* something I ought to be able to do myself:
>>
>> (a) I can't figure out whether I have to remove the steering wheel or
>> not. The Chilton manual (for LH-series vehicles up to 2001) says to
>> remove the steering wheel first, but the Chrysler manual seems to allow
>> for removing the steering column with the wheel still in place.

> Unless its just for convenience in clearance I don't see why you'd
> need to remove the wheel if you are taking the whole column out. If
> you do take it out make sure you don't let it rotate or it will mess
> up the clock spring wire I've been told on many cars.

Yes, that is emphasized all over the place.

>> (b) I've been reading that the refrigerant oil is highly hygroscopic
>> (absorbs moisture, even from the air), so what about the oil still in
>> the system? Will that have absorbed moisture through the leak that
>> allowed the refrigerant to escape, so that it will all need to be
>> drained and replaced?

> If you tape up the ends when you disconnect them you should be fine.
> Small amounts of water will be pulled out when the system if put back
> together and a vacuum is pulled on it to evacuate all the air and
> water vapor before putting freon back in.

According to the Chrysler manual, the evaporator retains 2oz. of oil and
the receiver/dryer retains 1oz. The manual also says to add 1oz. to a
new receiver/dryer, but is that where I add the additional 2oz. (so 3oz.
total) to replace the 2oz. that would have been in the old evaporator --
although whether it's still there or leaked out I have no idea -- or do
I pour that 2oz. into the new evaporator?

Perce

On Fri, 08 Apr 2011 09:20:39 -0400, "Percival P. Cassidy"
> wrote:

>On 04/07/11 07:16 pm, Ashton Crusher wrote:
>
>>> It's about 6 months since our '02 300M's A/C quit with a hissing sound
>>> and a sweet smell in the cabin. I bought a replacement evaporator,
>>> heater core and receiver/drier a while back but haven't yet installed them.
>>>
>>> I've been reading the service manual and have questions:
>>>
>>> 1. A lot has to be removed to get at the evaporator and heater core. Is
>>> it really so much of a hassle that I ought to try to find somebody who
>>> will do the job for me?
>
>> If you don't mind spending the money it's probably worth it. the
>> first time you do one of these kinds of jobs is a real learning
>> experience.
>
>Still thinking about it.
>
>>> 2. If it *is* something I ought to be able to do myself:
>>>
>>> (a) I can't figure out whether I have to remove the steering wheel or
>>> not. The Chilton manual (for LH-series vehicles up to 2001) says to
>>> remove the steering wheel first, but the Chrysler manual seems to allow
>>> for removing the steering column with the wheel still in place.
>
>> Unless its just for convenience in clearance I don't see why you'd
>> need to remove the wheel if you are taking the whole column out. If
>> you do take it out make sure you don't let it rotate or it will mess
>> up the clock spring wire I've been told on many cars.
>
>Yes, that is emphasized all over the place.
>
>>> (b) I've been reading that the refrigerant oil is highly hygroscopic
>>> (absorbs moisture, even from the air), so what about the oil still in
>>> the system? Will that have absorbed moisture through the leak that
>>> allowed the refrigerant to escape, so that it will all need to be
>>> drained and replaced?
>
>> If you tape up the ends when you disconnect them you should be fine.
>> Small amounts of water will be pulled out when the system if put back
>> together and a vacuum is pulled on it to evacuate all the air and
>> water vapor before putting freon back in.
>
>According to the Chrysler manual, the evaporator retains 2oz. of oil and
>the receiver/dryer retains 1oz. The manual also says to add 1oz. to a
>new receiver/dryer, but is that where I add the additional 2oz. (so 3oz.
>total) to replace the 2oz. that would have been in the old evaporator --
>although whether it's still there or leaked out I have no idea -- or do
>I pour that 2oz. into the new evaporator?
>
>Perce

I'd put it in the new evaporator if you are leaving everything else
alone.