Packard Forum Index » Post-War (1946-54)

For awhile now I've been observing coolant seeping out of a small area at the top of my transmission cooler and decided it was time to repair it or replace it with a unit that I had removed from a '54 Clipper shortly after I purchased my car. When I removed my original cooler last year to make it easier to paint the engine I found that both necks were rusted to the point of being too far gone to repair so a friend of mine with a muffler shop cut the old ones off and replaced them with mild stainless necks that we cut from exhaust pipe. Further inspection showed that there were other weak areas in the cooler body but except for this latest leak it's still pretty solid. Anyway I didn't want to have the car down while I repaired the original cooler so I cleaned up the spare unit which surprisingly still had some pretty solid necks on it except for some deep rust pitting and two small pin holes. I thouroughly cleaned the the necks and wiped both the inside and outside with a skim coat of JB Weld then after shaping them up with a file I coated them inside and out with some left over POR15 Gas Tank Liner. Fast forward to a about an hour ago and I find out that Packard decreased the steel line size from 5/16" to 1/4" at some point which of course requires changing out the inverted flare fittings on the spare cooler unless I use 1/4" to 5/16" adaptors which I'd rather not do. My question is this, the inverted flare fittings are of course NPT on the end that screws into the cooler and they are going to be tight! What are the chances of removing the old fittings without breaking the boss loose on the cooler itself?

Attach file:

---

  (116.64 KB)

I would replace the 1/4" transmission cooler lines with new 5/16" tubing. I don't think this change will cause a pressure loss to be concerned about. Ross, what do you think?

(o{}o)

JW, My '53 already has the 5/16" lines. It's the '54 cooler that had the 1/4" lines and I need to replace them so I can use my larger lines. No worries anyway, I was too impatient and went ahead and removed them without breaking the fitting bosses loose. Now all I need are two of these and I can install it.

Attach file:

---

  (10.06 KB)

That's a 1/8" NPT to 5/16" tube fitting that will screw right into the '54 cooler without having to use adaptors.

Gator, sorry about my mistake about which cooler you were dealing with. Glad you got the fittings off of the cooler. Given the problems a transmission oil leak can cause to a transmission and cooling system, you my want to re-think about using one of questionable integrity.

(o{}o)

I believe the actual cooler core inside the cooler assembly is stainless steel (or monel) so the likelyhood of corrosive perforation of that and thus a leak of coolant into the transmission fluid is very unlikely. Can't say I've ever heard of it happening.

Gator -

Those fittings are known as "street elbows"; any good, local, parts store that stocks an assortment of Edelmann (or equivalent brand) fittings is likely to have what you need. Be sure to take your cooler and fittings along for comparison.

There used to be purposed sockets for installing/removing these fittings, which conformed to the unusual shape and helped prevent collapsing the female opening. However, I've been able to use a wrench (even a Crescent type) by first installing a male fitting (aka - "nut") into the female opening of the street elbow - not much more than finger tight - to buck up the brass stock.

Veteran mechanics always seem to have an assortment of used fittings laying around for this sort of thing, but if you don't, it may be worth purchasing a few of the sizes of "nuts" as well - cheap insurance.

You can get these fittings from Hydro-e-lectric in Florida.
They used them for new 90 degree turns on my new elecric/hydraulic window hoses. They are VERY helpful.

i had to also replace the ends on the cooler, i used exhaust adapters, then used the expanded section , and cut a sliver of it off and braze it on by the end to hold the hoses on .

Quote:

Interestingly, this topic relates tangentially to the discussion of what ATF to use in the Ultramatic because certain fluids support the formation of corrosion inside transmission coolers, particularly if Dexron II was used for any appreciable length of time.

Dexron III (today marketed as Dex/Merc or just ATF) has great corrosion inhibiting properties and is backward-compatible to Type A.

If we were having this discussion in the 1970's, I'd be wary of using a used cooler, but if it holds good pressure now on the transmission fluid side, I'd go ahead and use it today without fear-- it's more likely to leak coolant out into the world than to cross-contaminate ATF and coolant if its not already leaking, given the advances in today's fluids. Just my 2 cents.