Cooler line advice?? (pics inside)

[slow_90firebird]

Hey guys I finally got almost all the stuff for my remote filter install.

I was planning on tapping into the feed line to the cooler. There are 2 spots I could use, one down by the frame and one up near the radiator. At both these locations, the cooler lines are attached with hoseclamps factory.

The issue I want to figure out before tearing into it is, the nipples on the new filter mount are 3/8" barbs. I went to napa and purchesed a length of 3/8" i.d. power steering line, and it fits perfectly over the barbs. It was the largest line he had.

I dont see how I will be able to stretch this over the steel hardline. The rubber hoses on there now seem bigger. Also I got a dual-end 3/8 brass barb to connect the old rubber hose to the new one, but I am not sure if 3/8 is going to be tight enough even if I double clamp it.

Any advise?

[ellis93]

They make hosebarbs that have compression fittings on one end. They work well for steel lines but they need to be tightened up pretty hard to seal well.

[slow_90firebird]

hmm i def dont wanna cut the line. I would like to be able to slip it back to stock if it doesent work out as planned for whatever reason.

Im guessing that you mean I could just slide the rubber hose off and work with what is there, slide the ferrul on and tighten it up. Then I would just need to cut off the ferrul to convert back.

Any idea where I could get these? Also, has anyone seen hose barbs to adapt two different I.D. hoses?

I might go see what depot / lowes has tomorrow night too.

[ellis93]

They can be had at Oriellys for shure.

[slow_90firebird]

Cool thanks but we dont have oriellys here. I might be getting the plumbing figured out today im going to see a guy on my lunch break about fittings.

I do have a more important question for you tranny experts though!
I know that if I ruptured a cooler line, the fluid flow comes from line pressure most likely from the valve body somewhere, and I would loose some or all of that pressure.
Now, after the fluid makes its way back into the tranny, where does it go? Does it dump back to the pan, or is the pressure actually used to operate something? I want to know, just incase the filter I put in ever got plugged up (it wont though) what would be affected besides the cooling?

[dazedandconfused]

Line preasure is what makes everything work. It makes the clutch packs engage. If you loose line preasure due to a leak or plugged filter you will run the chance of burning up clutch packs.

[ellis93]

Flow goes like this:filter-pump-regulator and fluid splits three ways. One feed the valve body. The other feeds a boost valve( and other stuff from there). The last feeds a switching valve that then feeds the converter and front clutch. From the converter, fluid flows back to the switching valve and from it to the cooler. From the cooler, fluid runs to lube the output shaft and rear planet in a 727, all of that would be intermediate in a 518. This is in neutral, as is similar in reverse first second and third with the exception of the boost valve supplying different things. Pressure in cooler lines could get as high as 95 pounds, so says the almighty ATSG trans manual.

[slow_90firebird]

Cool thanks that's what I needed to know. So the fluid from the cooler is used for lubrication but not clutch or band engage.

[ellis93]

Ya but cooler flow needs to be as free as possible. Other wise expensive hard parts will get burnt.

[dazedandconfused]

If it gets plugged or springs a leak you will burn the clutches up along with allot of other parts. Trust me you know from experience.

[ellis93]

No doubt. It is a turd deal whenever it happens

[slow_90firebird]

Well I got all the hose I should need and some new fittings to fit it too!

Now I need to decide where to tap into the circuit. I noticed there appears to be a little balance tube that allows some fluid to skip going thru the cooler. I can either put the filter before or after that .

Also need to figure out weather the upper or lower line going into the cooler is the feed line. Guess il have to pull one off and start the truck to see.

[dazedandconfused]

I'd put it after the ballance tube.

[slow_90firebird]

I was actually thinking if I have enough hose maybe I could replace that whole rubber hose assembly all together. But that would delete the balance tube.

It would be nice though my stock rubber hoses are getting kinda soft and sweaty with almost 250k on them

[slow_90firebird]

Ok I deleted the stock nasty swelled up lines and used my new hose and some screw clamps very sparingly and here is what I did today:

Stock sweaty lines:


Filter Head Mounted


Special brass fittings that werent supposed to need clamps (didnt work for me)


Up from Feed line to filter


In and out of filter to cooler


In and out of cooler and back to trans


---------------------------


Went around the block and up the highway an exit and seems to drive the same... no leaks (yet haha) dunno why they needed a balance tube anyway before the cooler, there is none at the heat exchanger and thats the same circuit.

Now when it cools down a little I gotta drop the pan and do all that stuff.