[DeTomaso] Exploding air conditioning system - Fake News or an accident waiting to happen?

Sun Jun 19 11:15:44 EDT 2022

Charlie,

I suspect the 'exploding' hose stories are mostly related to improper conversions to R134a reuse of old hose and where a high-pressure cutoff switch was not installed, the R134 system runs at higher pressure than the R12.

Not only related to Pantera's but to classic cars as a whole I once read it is a common problem with classics that sit for long periods over winter as the compressor shaft O-ring will develop a flat spot and allow refrigerant to weep out over time.

Julian
________________________________
From: DeTomaso <detomaso-bounces at server.detomasolist.com> on behalf of charlesmccall at gmail.com <charlesmccall at gmail.com>
Sent: Sunday, June 19, 2022 7:32 AM
To: 'Thomas Törnblom' <thomas at hax.se>
Cc: detomaso at detomasolist.com <detomaso at detomasolist.com>
Subject: Re: [DeTomaso] Exploding air conditioning system - Fake News or an accident waiting to happen?

Thanks Thomas
Yes, I've replaced the compressor. I've replaced all the hoses with Mike Drew's help many moons ago. Several shops have sniffed around with a leak detector but haven't been able to find where it's going.

Classification: Restricted

-----Original Message-----
From: Thomas Törnblom <thomas at hax.se>
Sent: Sunday, June 19, 2022 16:06
To: charlesmccall at gmail.com
Cc: detomaso at detomasolist.com
Subject: Re: [DeTomaso] Exploding air conditioning system - Fake News or an accident waiting to happen?

My AC system was empty when I bought the car. The compressor had been replaced with a unit from Hall by the previous owner.
I had the system converted to R134a and a marginal hose was replaced at the same time. It worked fine for two years, and then it was empty again. I had it recharged a few times and had the axle seal replaced, which made no difference. I bought a leak seeker and while playing with that I noticed it indicated refrigerant around the compressor. Turns out that the gaskets on on R12 compressors may not seal properly for the smaller R134a molecule. I bought a new Sanden 508 compressor designed for R134a and it has been working great for many years.
I had to refill the system two weeks ago and that was due to a bad O-ring and fitting on the drier. It has probably come lose when I pulled the engine last and had to fold away the condenser.

Have you replaced the compressor Charlie?

Cheers,
Thomas

> 19 juni 2022 kl. 15:06 skrev charlesmccall at gmail.com:
>
>    Hi all
>
>
>   In the 20+ years that I've had my Pantera, the air conditioning has
>   only worked for a few sporadic months. It works fine when charged, but
>   we can't find the source of the leak, despite having changed nearly
>   everything that could be changed. So the system was charged again a few
>   weeks ago preparing for my trip to Le Mans Classic, and this guy did
>   find a crimp that looked suspicious, so we'll see how long I have cool
>   air.
>
>
>   Anyway, I seem to remember that we all know that at higher speeds
>   (85mph+) there is a low pressure area behind the AC condenser, which is
>   why some people move them up front. I also seem to remember something
>   about the system pressure getting too high because of inadequate
>   cooling, and this high pressure causing the system to explode. Is this
>   correct? Is there a risk from leaving the AC on full speed, non-stop
>   for hours on end of high speed highway cruising with the stock
>   condenser set-up?
>
>
>   Thank you!
>
>                         Classification: Restricted
>
>
> !DSPAM:62af1f4816842729424764!
> _______________________________________________
>
>
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-------------- next part --------------
   Charlie,

   I suspect the 'exploding' hose stories are mostly related to improper
   conversions to R134a reuse of old hose and where a high-pressure cutoff
   switch was not installed, the R134 system runs at higher pressure than
   the R12.

   Not only related to Pantera's but to classic cars as a whole I once
   read it is a common problem with classics that sit for long periods
   over winter as the compressor shaft O-ring will develop a flat spot and
   allow refrigerant to weep out over time.

   Julian
     __________________________________________________________________

   From: DeTomaso <detomaso-bounces at server.detomasolist.com> on behalf of
   charlesmccall at gmail.com <charlesmccall at gmail.com>
   Sent: Sunday, June 19, 2022 7:32 AM
   To: 'Thomas Toernblom' <thomas at hax.se>
   Cc: detomaso at detomasolist.com <detomaso at detomasolist.com>
   Subject: Re: [DeTomaso] Exploding air conditioning system - Fake News
   or an accident waiting to happen?

   Thanks Thomas
   Yes, I've replaced the compressor. I've replaced all the hoses with
   Mike Drew's help many moons ago. Several shops have sniffed around with
   a leak detector but haven't been able to find where it's going.
   Classification: Restricted
   -----Original Message-----
   From: Thomas Toernblom <thomas at hax.se>
   Sent: Sunday, June 19, 2022 16:06
   To: charlesmccall at gmail.com
   Cc: detomaso at detomasolist.com
   Subject: Re: [DeTomaso] Exploding air conditioning system - Fake News
   or an accident waiting to happen?
   My AC system was empty when I bought the car. The compressor had been
   replaced with a unit from Hall by the previous owner.
   I had the system converted to R134a and a marginal hose was replaced at
   the same time. It worked fine for two years, and then it was empty
   again. I had it recharged a few times and had the axle seal replaced,
   which made no difference. I bought a leak seeker and while playing with
   that I noticed it indicated refrigerant around the compressor. Turns
   out that the gaskets on on R12 compressors may not seal properly for
   the smaller R134a molecule. I bought a new Sanden 508 compressor
   designed for R134a and it has been working great for many years.
   I had to refill the system two weeks ago and that was due to a bad
   O-ring and fitting on the drier. It has probably come lose when I
   pulled the engine last and had to fold away the condenser.
   Have you replaced the compressor Charlie?
   Cheers,
   Thomas
   > 19 juni 2022 kl. 15:06 skrev charlesmccall at gmail.com:
   >
   >    Hi all
   >
   >
   >   In the 20+ years that I've had my Pantera, the air conditioning has
   >   only worked for a few sporadic months. It works fine when charged,
   but
   >   we can't find the source of the leak, despite having changed nearly
   >   everything that could be changed. So the system was charged again a
   few
   >   weeks ago preparing for my trip to Le Mans Classic, and this guy
   did
   >   find a crimp that looked suspicious, so we'll see how long I have
   cool
   >   air.
   >
   >
   >   Anyway, I seem to remember that we all know that at higher speeds
   >   (85mph+) there is a low pressure area behind the AC condenser,
   which is
   >   why some people move them up front. I also seem to remember
   something
   >   about the system pressure getting too high because of inadequate
   >   cooling, and this high pressure causing the system to explode. Is
   this
   >   correct? Is there a risk from leaving the AC on full speed,
   non-stop
   >   for hours on end of high speed highway cruising with the stock
   >   condenser set-up?
   >
   >
   >   Thank you!
   >
   >                         Classification: Restricted
   >
   >
   > !DSPAM:62af1f4816842729424764!
   > _______________________________________________
   >
   >
   > Detomaso Email List is not managed by POCA Posted emails must not
   > exceed 1.5 Megabytes DeTomaso mailing list
   > DeTomaso at server.detomasolist.com
   > [1]http://server.detomasolist.com/mailman/listinfo/detomaso
   >
   > To manage your subscription (change email address, unsubscribe, etc.)
   use the links above.
   >
   > Members who post to this list grant license to the list to forward
   any message posted here to all past, current, or future members of the
   list. They also grant the list owner permission to maintain an archive
   or approve the archiving of list messages.
   >
   > !DSPAM:62af1f4816842729424764!
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