1955 Eldorado Transmission oil Cooler

[Munich]

Hello,
I have a 1955 Eldorado equiped with the "Harrison" transmission oil cooler. This small oil cooler is mounted on the right side of the transmission oil pan and is cooled by hot water from the engine block.
Oil from the rear pump of the transmission flows through the cooler when the pressure at a control valve reaches 60 PSI and flows than back into the oil pan. Shop Manual 1955 Page 14-1 and 14-6
Now is the waterflow on the lower side rusted through from inside by many points.
Sorry I have many questions: Does the difference of 20 hp (eldo 270 hp  instead of 250 hp series) really need this small oil cooler, cooled with hot water from the engine.
And if I connect the oil outlet from the pump directly to the inlet from the oil pan without cooling, does the oil temperature really dangerous  increase and damage the transmission?
I don`t know the average and max. temperature of the transmission oil
Knows someone where I can get a new NOS oil cooler or who can rebuild it.
Has someone a explosion view
I don`t have opened the cooler yet but I will do it the next time
I am very happy for every helping answer, I am shure I´m not alone with this problem
Gerhard

[Eldovert]

Gerard,
You could probably get by without the cooler considering how this car would be driven. That is to say, you are not going to be driving around using all 270 HP. The two halves of the cooler look like they are brazed together.
Cheers, Pat MacPhail

[dplotkin]

Post removed due to non-applicability.
Dan

[Eldovert]

Gerard,
While it is always best to keep the car as engineered, Cadillac only placed the cooler on the 270 HP engine and the commercial chassis cars. If you are tooling around the waterfront in your Eldorado it is unlikely the transmission will overheat...If you are into loading everyone in the car pulling the Grapevine in the middle of summer...you need all the cooling you can get.The 60 Special never had cooler and can't recall seeing many of them sitting at the side of the road with flames shooting from the tranny. These transmission are way tougher than than the Jetaway in my 56.
Cheers, Pat MacPhail

[Roger Zimmermann]

This transmission is exceeded only by the Dynaflow(s) for inefficiency. Half the shifting is done by flushing and filling a second fluid coupling. That's not one but two fluid couplings pushing around a 4,000+ pound car.

Dan, you are not reading the title: the car is from 1955 not 1956! The transmission you are describing is the second Hydramatic generation (1956 to 1964); the 1955 models had the first Hydramatic generation .
Only the Eldorado engines had a transmission with oil cooler; the regular engines had a transmission without it.

[dplotkin]

Indeed you are correct. I must pay closer attention, thought he had a 56.

Dan