On the plus side, it's like 2 transmission flushes in 24 hours

[6716]

To cut to the chase: I think I need help figuring out hydraulic / brake line and the connectors.

So, the transmission cooler line, passenger side, at the radiator, has popped out on the highway two days in a row. Dropped all my transmission fluid. First time I had a roadside assistance tow, second time I was able to exit and pull into a gas station.

Now, I replaced the two shorter lines a couple of months ago, because they were easier to replace than the two back lines. One of the back lines had a small hole, so I cut out the bad part and spliced in 1/2" ID fuel line.

A couple of things:
1. A guy at a transmission shop told me the fuel line was likely to burst at some point, not necessarily from the pressure, but from a reaction between the ATF and the rubber hose.

2. I think my rubber hose splice is too short, since the line doesn't stay in that snap-fit holder on the fan shroud. That's the only reason I can think that the line would pop out (a) after months of not popping out and (b) the day after popping out. I mean, I think I got that little snap clip back in there correctly. When I went to put the line back in yesterday, and again today, the little clip was still in there. The line wouldn't go back in with it in. So I took it out, put the hose back in, and put the clip back in. Filled it up, and I drove a good 100 miles after the second incident, and it's holding tight otherwise now.

Do I just use a longer piece of fuel line to address what I think is the problem?

Or should I use brake line, and if so, how do I make the connection hold when it is basically just in the middle of a piece of transmission cooler line?

Or have I completely breezed right past some other problems and not noticed?

Don't feel like spending $400 to have the back lines changed at a transmission shop, don't know that I am up to taking them on, espcecially now in the cold.

Thanks.

 

[meerschm]

you could use some 3/8 brake line and brass compression fittings from Home Depot or the local hardware store.

other wise, you could use transmission cooler hose (rock auto or the local store) would be compatible with the fluid.

I would recommend two hose clamps on each end. and if you can, flare the end of the tubing a bit. this can help keep the rubber tubing from sliding off.

is the 1/2 inch too big? did you try some 3/8?

 

[6716]

Aha!

I think it was just that I didn't know that the proper connector was called a compression fitting.

I'll go to the hardware store yet tonight.

The 1/2 inch is maybe a little big. I have it on there now with hose clamps. At first it leaked a bit, but I kept tightening the hose clamps, and it has been good since.

I might not have written it my post very well.

The splice is good, it holds fluid.

I think the reason the perfectly good, totally unspliced, and pretty much brand new short cooler line pops out of the radiator is that my splice on the long line is too short, and it puts pressure on the connection at the radiator, so the line pops out.

So if I am going to change my splice, I thought I would look at changing the splice material as well.

The line has to bend a little, so that's why I opted for the fuel line at first.

hmmmm

 

[gmcman]

Do you have the clip inserted to hold the cooler line in the radiator?

 

[6716]

Do you have the clip inserted to hold the cooler line in the radiator?

I do. And did. Or so I thought. And still think.

When I first did the repair on the lines a couple of months ago, I thought I had the clip in properly. And it held for a couple of months.

Then yesterday, on the side of the highway, I opened the hood and saw the line 2" back from the radiator.

When I got it back to the house, the clip was still in there. The line would not go back in with it there. So I pulled it out, put in the line, and put the clip back in.

And then today when it happened again, it was the same situation. Line popped out. Clip still in. Pull clip, re-insert line, refill fluid, off I go.

And then I drove fine for the rest of my driving-filled day, though I did check the connection a number of times.

Weird, eh?

Only thing I can think is that I have to take some of the torque off of the small line by making a longer splice. Seems like it ought to hold, otherwise (assuming I have that clip in there correctly, though it's hard to think of how it could be done incorrectly).

 

[christo829]

Can you see a yellow line near the end of that pipe, where it plugs in to the radiator connection?

On the Jiffy-tite connections there's an indicator line on the pipe...a roughly 1mm thick yellow line. When you put the pipe
in to the conector, if you can see the line, it's not fully inserted. I had to push on mine snd give it a slight wiggle before
it snapped in to place. One of mine seemed to snap in to place, and I couldn't pull it back out, but I could still see the line.
I pulled it from a different direction, and it did pop back out.

Even on my badly corroded pipes, the line was still visible, so hopefully you can still see yours.

If it goes all the way in to the point that the line is hidden, and still pops out, the clip itself may be bent, or else
there may be some corrosion in the socket keeping the clip from snapping down properly over the pipe.

If you do decide to do the full replacement, it can be done without a lift and without removing the exhaust, but
the spacing between the exhaust and the area where the pipes clip in to the transmission is *really* tight, even with
the trans & crossmember lowered. Also, the pipes slide in better if you've got at least 18" of clearance under the truck to maneuver
the pipes. The connections on the transmission itself are a real pain to get to, but there's a low profile tool for the Jiffy-tite
connectors that works well for those. The tool is Lisle 22930 3/8" Low Profile Disconnect. It actually had a tougher time with the
connectors between the pipes, ub by the power steering, as those were badly corroded.

Fuel line will start to break down after being exposed to the trans fluid for a few weeks. Actual trans cooler line that can handle
the high pressure as well as the fluid would be a preferrable alternative. If there's enough pipe, put a slight flare on the end that you're putting the
hose over, and get a good overlap. I used three clamps on my patch job until I got the correct pipes. Brake line with compression
fittings would be a much better solution for a patch.

Good Luck!

Chris

 

[Wooluf1952]

Two things I would add;
If you re-use the old spring clip ( the service manual recommends getting new ones ) squeeze it with pliers a little to make it tighter.
When you push the clip on, put one leg in the slot and then push the other end in. If you push it straight in, it spreads it apart more and lessens the spring tension.

 

[meerschm]

really should not pop out of the radiator. i suspect the clip is bent or otherwise not working. where did you get the short length of tubing that enters the radiator? it may be incorrect. I suspect they sell short tools that kind of work, intended for flushing, not for operation. the geometry of the end of the tubing is critical.

here is a photo I took of my lines where the connect. you can see the yellow line in each case, not connected, or connected.

View attachment 31469

 

[6716]

Can you see a yellow line near the end of that pipe, where it plugs in to the radiator connection?

On the Jiffy-tite connections there's an indicator line on the pipe...a roughly 1mm thick yellow line. When you put the pipe
in to the conector, if you can see the line, it's not fully inserted. I had to push on mine snd give it a slight wiggle before
it snapped in to place. One of mine seemed to snap in to place, and I couldn't pull it back out, but I could still see the line.
I pulled it from a different direction, and it did pop back out.

No yellow stripe, and it's a new part from NAPA.

Maybe I'll sharpie a line on there.

Two things I would add;
If you re-use the old spring clip ( the service manual recommends getting new ones ) squeeze it with pliers a little to make it tighter.
When you push the clip on, put one leg in the slot and then push the other end in. If you push it straight in, it spreads it apart more and lessens the spring tension.

Got a new clip with the new part a couple months ago. I think I put it on there correctly, but maybe I didn't. I'm not sure I know it's right, but it kind of looked like it went back in there the way it was when I took it apart.

really should not pop out of the radiator. i suspect the clip is bent or otherwise not working. where did you get the short length of tubing that enters the radiator? it may be incorrect. I suspect they sell short tools that kind of work, intended for flushing, not for operation. the geometry of the end of the tubing is critical.

here is a photo I took of my lines where the connect. you can see the yellow line in each case, not connected, or connected.

The tubing is spliced into the long cooler line. The short cooler line is the stock part.

 

[6716]

I made a new patch, this time long enough, and using the correct materials.

Here's what I think happened:

For one, the first patch I made in the long cooler line was too short, I think. This had the effect of putting constant pressure on the line going into the radiator, pulling it straight back out of the fitting at the radiator. The short cooler line wouldn't stay clipped into that spot on the fan shroud. Both times when I dropped all the fluid, the line was pulled back about 2" from the fitting at the radiator.

For two, I used fuel line for the patch. When I took the patch off, the line was swollen, and I think it may have also been shrinking in length as it got bigger in the middle. I think it may have just happened that the shrinkage put pressure on the radiator fitting -- causing that to fail -- but it may not have been too much longer before the fuel line ruptured, anyway.

This time I used 3/8" ID transmission oil line, and better hose clamps. One test drive and I'm not leaking at the patch, so we'll see how it goes.

 

[SS Laser]

I also have a small issue with the passenger side trans cooler fitting. I am finding a few drips on the garage floor all the time and it looks like the pass side trans to rad/trans cooler fitting is leaking?

This is months heck maybe a year after putting in some rubber trans hose for the rusty line pin hole leak issues.

I never removed that fitting at the rad. But it does move around now with the rubber hose Vs metal line. Not much but I bet some while driving. I need to get a new clip and pop it apart. I had hope there was a o ring in there causing the leak. What should I do guys?

Thanks for any help.