Re: [Chrysler300] Transmission cooling line failure inside radiator
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Re: [Chrysler300] Transmission cooling line failure inside radiator

I'm guessing being almost 60 years old has something to do with it 😄

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On Jun 7, 2016, at 10:22 AM, John Grady <jkg@xxxxxxxxxxxxxxxxx> wrote:

I agree with John , about where the trouble would be,  100% . Radiator or engine cooling will not be hurt by oil.


From that perspective maybe run trans without cooler ,for a week or so drive 30 miles daily, the higher vapor pressure of uncooled oil will drive water out the fill vent sooner. Maybe even leave that loose or open , let water vapor out . And change trans fluid a few times to get any antifreeze out. I agree that oil in radiator water probably not a big deal , most will end up in high places anyway. Including top of radiator puddle , so running water in it and changing a few times ought to fix that part . Does anyone know the normal running temp of a torqueflight under load? The max temp? Like pulling something? These same transmissions in Plymouths sometimes had an ‘air cooled “ converter, vent grill in bell housing,  and no lines at all. The point being if trans is OK at 210-215  that is good for getting water out. So leave radiator loop out of it for a while. Trans probably does not get real hot in normal driving anyway ,on flat roads,-- maybe radiator then actually  heats it on cold day to 180-190? .It is converter loading (torque) that heats it..climbing mountains or pulling  trailer . I seem to remember something like 235 + is still ok . I do know optimal temps for gear oil is in the 125 F range. ( have small hydroelectric plant, 200 HP 9;1 gearbox, on 24/7 got into all that)


I am interested in WHY it leaked..I believe ,and Don V can correct me, that the cooling lines are not under any big pressure..maybe 20 psi? the return is just like a drain ---after whatever flows into converter  ( controlled orifice or regulator) gets out by that line (why this happened , water ran back)


Given that the cooler is a pretty substantial steel tube, how does it “split” ? maybe not on your car ---? but a forensic ripping it out of a bad radiator,  see what we have would be very valuable. This is a very bad thing to happen to a 300. That it happened to a few of us says cooler must rust out or something we are not aware of. ; This has implications on testing and rebuilding / recoring radiators too. Or trusting old good ones. You could be driving along on your long trip, this happens and you are truly done for, as you wopuld not even know it is happening. You are lucky, believe it or not, from that view. . Looks like if not noticed you are out 5-8k and huge inconvenience and hassle of getting car back etc. . Worth getting to bottom of the WHY. . Later ones ( Dakota?) might be plate type heat exchangers, sheet metal thin box with welded edges. That I could see failing. On external air only ones, have to go as big as you can get, as they have no peak capacity. Gallons of water can soak up a lot of heat for 10 minutes.(climbing hill steep long ) , 5 lbs of aluminum in air cannot do that.


From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of John Nowosacki jsnowosacki@xxxxxxxxx [Chrysler300]
Sent: Monday, June 06, 2016 6:49 PM
To: Ray Melton
Cc: chrysler300@xxxxxxxxxxxxxxx
Subject: Re: [Chrysler300] Transmission cooling line failure inside radiator


I had the same thing happen to my 57C.  I had the radiator re-cored with new oil cooler.  I eventually had the transmission rebuilt.

A person I trust in the business said that the oil in the cooling system was not as bad as the water in the transmission system.

He said it might only be a matter of time before the friction material inside the transmission would give up the ghost having been contaminated with water.  They're made to run in transmission oil, not water.  He said that the bonding agent holding the friction material in place was water soluable, and that the contamination would lead to eventual separation (or not, depending on how bad).


On Mon, Jun 6, 2016 at 6:15 PM, Ray Melton rfmelton@xxxxxxx [Chrysler300] <Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:


I have transmission fluid contaminating the cooling system, and water contaminating the fluid in the transmission!  Seeking Advice.  How to decontaminate transmission and entire cooling system.
Description of problem:   After manually refilling the Type F fluid (about 10 quarts) in the newly rebuilt Torqueflite in my 1957 300C, we came back the next morning to find a big pool of water and transmission fluid under the car!  They removed the transmission pan, which let out a considerable amount of water and oil mix.  The Torque converter was completely drained.  There were remnants of pink oil visible on the cooling passages when the radiator cap was removed.  The radiator was drained of the remaining oil and water mixture. 
It was quickly concluded that the tubing for transmission fluid at the bottom of the radiator had ruptured internally while the engine was being run to perform the fluid fill process, pumping high-pressure pink fluid into the radiator water while running.  But after shutting down for the night, the heavier water pushed back through the (now unpressurized) ruptured oil cooler line inside the radiator, which eventually pushed oil and water out some overflow location near the back end of the transmission. 
The transmission was being run in Neutral, Drive and Reverse during the fluid fill process, so we were unwittingly getting some water back into the ruptured oil line as soon as the engine was shut down and the transmission coolant line pressure went to zero.  Then as soon as the engine was restarted, we were pumping some oil into the radiator and also pumping some oil/water mix through the transmission. 
The entire cooling system (radiator, all hoses, all water passages in the engine block and heads, etc.) is now contaminated with at least some amount of transmission fluid, so I am seeking advice on how to best remove that oily residue.  We plan to blow out the transmission fluid lines at the bottom of the radiator to remove as much residual fluid as we can, and then just cap off the inlet and outlet lines, so there will no longer be the original oil/water heat exchanger functionality.  (That transmission fluid cooing aspect will be addressed separately) 
Our tentative plan is to refill the radiator with a mixture of water and a water-based degreaser like Simple Green, or Purple Power, then run the engine until it's good and warm, then drain out all the coolant with solvent and oily contaminant.  We will probably do the solvent flush routine until we see no further trace evidence of transmission oil in the water coolant -- at least twice -- and then refill with distilled water and a water-based rust remover called Evapo-Rust to remove some of the rust that is most certainly all through the internal coolant passages after the vehicle sat idle for 17 years.   I was planning to run that rust-remover coolant combination  for several hours, or at least half a dozen hot/cooldown cycles before going with a more permanent water and antifreeze mixture for everyday driving.  
What to you guys think of that plan to remove residual tranny oil from the coolant system?
We plan to connect the transmission cooling lines to an external auxiliary oil-to-air transmission cooler that will be located in some open space roughly in front of the bottom of the radiator wherever it looks like there might be some air circulation path.   I was not planning to have any fan-forced airflow device, relying just on convective cooling from a fairly generous finned heat exchanger in whet will likely be a rather turbulent air flow region (but I have NO way of knowing that!)  I don't know what temperature the transmission fluid would like to be when it goes back into the tranny after the cooling process, although I suspect it would be somewhat higher than the temperature in the radiator, around 190 F as governed by the thermostat.   I will have no reasonable way to tell what the oil temp is when exiting the auxiliary heat exchanger, so I won't know if the heat exchanger is doing a good enough job.  I know the air temperature will usually be considerably cooler than the 190-degree water in the radiator, but I also know that the heat exchange coefficient of the oil-to-air cooler is much lower than the HX coefficient of the original oil/water cooler system.   
What do you think of the oil-to-air auxiliary heat exchanger idea to replace the original oil-to-water system? Any thoughts or advice are welcomed!   



"A government big enough to give you everything you want, is big enough to take away everything you have." ... Thomas Jefferson 


Posted by: John Nowosacki <jsnowosacki@xxxxxxxxx>

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