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

For what it is worth , Ray, I too would not put any stuff in, just plain water and trans fluid.. But your offer to watch and see what happened is beyond valuable. That is critical info you can get now-----that will REALLY help all of us.


From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of Ray Melton rfmelton@xxxxxxx [Chrysler300]
Sent: Tuesday, June 07, 2016 9:50 PM
To: Ron Waters; Chrysler 300 Club, Int'l
Subject: Re: [Chrysler300] Transmission cooling line failure inside radiator


Hi Ron -

Thanks for your thoughts.  I have never seen what's inside my radiator, especially at the bottom where the transmission oil cooling function occurs.  I pictured a labyrinth of tubing in the bottom "tank" of the radiator, where the tubing is exposed to the relatively cooler water in the radiator, just before the coolant is discharged out the bottom.  And I pictured that the rupture would have occurred in some portion of the tubing, leading to transmission fluid leakage into the coolant while the transmission is operating and those lines were pressurized.  Or is my visualization incorrect?

The radiator had been rebuilt less than one hour operating time before this event, although I have no idea what they did inside, especially at the bottom.  They may not have even looked at that part of the radiator!  So, the radiator is coming out and going to the (supposedly) best place in town, and I  want to watch just what they are doing every step of the way!  I may even ask if they can  rebuild it to a 4-core configuration instead of the stock 3-core version.  And of course, I'll be especially interested in seeing what goes on in that bottom tank with the transmission cooling lines. 

After draining everything from the transmission pan, we put a blow-gun all over every tranny part accessible with the pan removed, (including valve body and now-empty torque converter),  and then we even put a big desiccant bag in the bottom of the pan where the filter used to reside, closed it up and left it there for two days.  Also blew out the new stainless lines from the transmission forward to the radiator.

Next plan for cooling system after rebuilt radiator (top, middle and bottom!) is reinstalled:  we will put some degreaser (Awesome, Simple Green, Purple Power, etc.) into the radiator water while we begin the transmission refill process.  Then run it for a couple of hot/cold cycles, then drain out the transmission fluid.  Rinse and repeat.  Plan to fill and drain the transmission at least twice to flush out any residual water.  Also plan to fill and drain the radiator (and entire cooling system as best we can) at least twice, leaving heater in "ON" position to get everything out of there, too.  Finally, refill radiator ith conventional 50/50 green antifreeze (plus Redline WaterWetter) and keep and eye on everything from temperature to possible pink oily slime on top of radiator water!  Change again if necessary.

Then, just cross fingers (arms, legs, toes and eyes, too!) and hope the brief exposure to water (with EvapoRust) did not damage anything inside the zero-hour rebuilt transmission!

I will keep the membership posted on the progress (success or failure) of this miserable problem!

Ray Melton

1957 300C convert

Las Cruces, NM     (575)642-3151


On 6/7/2016 6:04 AM, Ron Waters wrote:

Ray -


Job One would be to have a quality radiator shop rebuild your radiator. There is a breech between the cooling tank on the bottom and the radiator core itself. Your radiator is toast. Be sure to get a warranty as well.


There is no need to jury rig auxiliary tranny coolers, etc. Once you have a new radiator, the system will work as expected.


Removal of coolant from transmission: I would drop the pan and let all fluid drain out. Also drain out the torque converter. Let everything drain for a while. Then refill with fresh tranny fluid. You may want to work the car through the gears a few times. Then shut engine off and drain the tranny again. Then refill with fresh fluid again.


Removal of tranny fluid from coolant: Drain out cooling system, which may include heater core if that was connected to the system. Add a weak solution of coolant and water (I wouldn't run pure water thru the engine). Get engine up to operating temperature. Then cool down and drain cooling system. Refill with fresh coolant 50/50 mix and you should be in good shape.






----- Original Message -----

Sent: Monday, June 06, 2016 6:15 PM

Subject: [Chrysler300] Transmission cooling line failure inside radiator


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!   


Posted by: "John Grady" <jkg@xxxxxxxxxxxxxxxxx>

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