Big Block Transmission Cooler Lines

[chilort]

There's been a puddle developing where the Swepty rests at night (well, a couple of puddles). The transmission cooler lines are cobbled together and are starting to leak quite a bit.

I was wondering what you all are using for trans cooler lines. The truck is a '68 with a matching year 440 and 727 from a c-body.

I've thought about ordering trans cooler lines from Year One for a B-body but Year One is so expensive and I'm not sure they'd work once I got them. I guess I could bend my own line, but would rather go pre-made if someone has them out there that work.

Thanks!

[nfury8]

Inline Tube or Fine Lines might have something, but they are pretty easy to bend your own.
You can either get short sections, usually up to 6', at the parts stores and piece them together,
or get a roll and custom make them. Some parts stores sell rolls, usually around 20-25 feet, or
Summit also sells rolls of tubing.

25 ft of 5/16" steel tubing is $29 at Summit. Don't make the mistake of buying stainless thinking it
will last longer. It will last longer, but it requires special tools to get good flares on it.

With a 25' roll, you should have enough left over to redo any original fuel lines that might also be
in need of attention.

[chilort]

Neither Inline nor Fine Lines make such a thing. I called to double check.

I really don't want to have to bend my own. I think the biggest reason is because I don't have a double flare tool to do the job right. Sigh.

[surfnuke9]

Unless you are a slave to originality, why dont you make them out of properly rated hose and fittings?

[chilort]

Unless you are a slave to originality, why dont you make them out of properly rated hose and fittings?

I'm not a slave to originality. I'm more of a slave to 1) easier is sometimes better, 2) what works really well, and 3) solving the conflict between 1) and 2).

If by "hose" you mean rubber hose, well, that's what is on it now and I really don't like the look of it (and it leaks). I don't even know what the proper routing for original looks like. The hoses that are on there now are just kind of hanging and sloppy. If I were to make my own, and that's what it is starting to look like it is going to take, then I can do a decent job with hard line.

[712edf]

A factor to consider about rubber hose vs metal lines is supposedly metal will disappate heat quicker.

[nfury8]

You can get a decent flare kit for steel lines for under $30.
It is a decent investment, considering it can also be used for
fuel and brake lines. Original routing isn't an issue, just keep
the lines away from the exhaust, fan blade and any pinch points.
Otherwise shoot them straight and over the axle.

For a little extra protection or insulation where the return line might
get closer to the exhaust, take a piece of 5/16" hose and slit it length
wise, wrap it over the line and secure it with a couple zip ties. Don't do
the whole length, just any areas where you want the extra protection.

You can kind of see what I am talking about here. There is at least 4 inches
between those lines and the exhaust, despite how the picture looks.

[chilort]

You can get a decent flare kit for steel lines for under $30.
It is a decent investment, considering it can also be used for
fuel and brake lines. Original routing isn't an issue, just keep
the lines away from the exhaust, fan blade and any pinch points.
Otherwise shoot them straight and over the axle.

For a little extra protection or insulation where the return line might
get closer to the exhaust, take a piece of 5/16" hose and slit it length
wise, wrap it over the line and secure it with a couple zip ties. Don't do
the whole length, just any areas where you want the extra protection.

You can kind of see what I am talking about here. There is at least 4 inches
between those lines and the exhaust, despite how the picture looks.

Looks really nice. Wanna bend me up a set? Ha.

So you used 5/16 line? Do you remember the thread on the fittings?

I've got a deep pan and pump extension sitting on a 727 I've got in storage waiting for my Super Bee. I'm half tempted to pull it and use it.

[nfury8]

My trucks are so tweaked, the lines on them wouldn't fit anything!

Those lines shown are actually 3/8" lines for the 46RH.
The OD requires larger lines. The 727 will use 5/16" cooling lines.

The fittings should all be 5/16" to not hinder the flow of fluid, the size
is based on the ID of the tubing they are used with. There is a pipe thread
in the transmission housing, and a brass adapter fitting that fits in it and
converts to the flare end. So if your adapter is good, you need a 5/16" female
tube nut for each fitting. If you buy the short parts store lines, they should
already be flare on the ends and have the male tube fittings on them. Unions
will be needed to hook the pieces together. If you measure really well and get
lucky, you might be able to piece a couple different lengths together and not
have to cut and flare anything, just bend, Tubing benders are pretty cheap also,
and the same goes with using them for brakes and fuel. I prefer to use a solid
length when possible, fewer points to leak.

You will then need to fit them to your cooler.

I did a similar repair on my 71's brake lines 2 weeks ago. Sprung a leak in the rear
line. Needed to fix it that day and didn't have any long pieces of 3/16" left over.
Measured and realized I needed exactly 10 feet from the tee to the rear axle.
Got a 4' and 6' piece with a union, made a 90 degree bend on each end and was good
to go. That was when I realized the master had sprung a leak also.

[Russ]

We need to get together sometime and compare since my truck has the same engine and tranny combo. I'm using the original 76 Chrysler lines from tranny to about mid point of the engine. I made new ones from that point forward since the radiator was different. I have them connected with short pieces of hose that is made for oil and gas. No leaks since I put the new radiator in in about 2003. I've had an 81 and 87 Diplomat, 87 Ram van, and an 87 5th Avenue and they all had a short section of rubber hose between the steel lines and the radiator.

[nfury8]

Chrysler didn't screw around needlessly. The in and out ports were in the same location
on all automatics for over 40 yrs! So in that regard, you could probably easily adapt lines
from just about anything rear wheel drive with a 727, 904, 999, 998, 500, 518, 42RH,
46RH, 47RH, 42RE, 46RE or 47RE and probably the 48RE!!! Every transmission guy I have
meet loves the 727/904 based transmissions. They usually make comments like
"Why mess with perfection?"

[chilort]

While the in and out ports might be in the same location, I got a feeling I'd be a bit f'ed by that stupid extra cross member my truck has if I tired to use tubes from something else. I just noticed this today on my recon mission.



I really hate that cross member.

Some of the joy at the radiator end of things:



Some of the funk in the middle:


I've got some 1/4 tube I think I'm going to use for making shapes then bend it up in the 5/16 line. This might take a little longer than I even originally though. Yay.

[nfury8]

Coat hangers and heavy bailing wire are excellent prototyping tools also.

Don't know if the cross member would be an issue or not, looks like there is quite a bit of room.
The lines generally hug the trans and oil pan.

That second pic shows what I usually see when rubber tube is used. For what it is worth, I have
replaced all my lines with solid line from the trans to the cooler. My motors flex very little, locking
mounts on the 440. I would probably use a short piece of steel tube on the right side,
like the left side shows. The barb isn't a huge issue, but steel tube will hold the curves better than
the rubber tube.

You will need unions like the last pic shows if you use parts store lines. That one doesn't look to be
leaking, just covered in junk from some other leak. Properly installed unions aren't a big issue,
but things look cleaner without them.

[chilort]

I buggered up my 1st attempt and will use a union on it. One union is going to be so much better than the 4 or more connections that were there. It should lower head pressure and also flow and cool better when I'm done.

I don't have locking mounts, but I do have the engine chained down.

[nfury8]

An excellent alternative. The locking mount is in my Fury, a chain just wasn't going to look right in there.
It used to have a chain. The 318 was breaking mounts every year! There were some serious quality
issues on mounts back in the early 90's. I am curious to see if the Magnum in my crew is going to need a chain.

4 unions in one line?!?! That is a bit much.

I don't have locking mounts, but I do have the engine chained down.

[chilort]

Schumacher creative services was supposed to offer a locking mount for the plate style engine mounts for the trucks. I bought one of their non-locking mounts and broke a stuff off while trying to tighten down one of the nuts. I hadn't even stepped up to a big wrench yet. I won't be buying any more of Schumacher Creative Services parts. I thought about using a fancier adjustable engine strap but chain was quite a bit cheaper.

It was exactly four "unions" but several junctions for sure. Even the line without the union was hard line out of the trans, a junction to high pressure rubber hose, a junction from high pressure hose back to hard line, from hard line to cheap rubber hose and then from cheap rubber hose back to hard line at the radiator. Hopefully I'll have time after work today to get it back together and fired back up.

[chilort]

Oh yeah! Got it wrapped up tonight after work.

Here's what the return line looks like:


I don't have a picture of the pressure line. It does have one union where I messed up a bend and made it too tight. So I cut the shortest section off and redid it. Fitting this one in around the shifter cable, kick down, brake lines (the way I have them routed at least), the extra cross member, and the exhaust was difficult.

If it is possible, the truck runs better. I think all of those joints were building too much head pressure for the tired old pump in the 727. At high speeds I had a ticking noise. That noise, as far as I can tell, is gone. If you got on the gas a little when you were cruising down the interstate it would get much louder. Now --- Nothing. Great. Now I need to figure out what it was that was doing the ticking in the trans just to make sure it makes sense.

[MountainMoparRobin]

Thats a transmission cooler line???

[712edf]

That was my first reaction, but I can see that the view is from the top and the line runs over to the frame, along the frame, then across to the passenger side of the radiator.

[chilort]

That was my first reaction, but I can see that the view is from the top and the line runs over to the frame, along the frame, then across to the passenger side of the radiator.

Exactly.

I don't know how they were routed originally. If they just kind of went straight like the ones that were on the truck, well, I really didn't want to do that. My goal was to hug the frame rail (without touching it) so that I have room to do stuff from under the truck without having those lines in the way.