02 2500HD Cooler Lines Leak @ New Radiator

[Ol'Jim]

Recently replaced the radiator on my truck, because one of the plastic tanks cracked. (I curse those things, as my 38 year old Monte Carlo still has the ORIGINAL rad in it!).
Rather than pull it & spend $160 to get 1 of the tanks replaced, I bought a complete new Napa replacement radiator. Easy enough to change out, but...
The unit has an engine oil cooler in the driver side tank, & a trans cooler in pass side tank.
All 4 fittings for the cooler lines are the quick-disconnect types, with a spring clip retainer in them.
I re-used the clips, and the lines. The female fittings on the radiator were new, (came with the new unit).
A couple weeks later, the upper trans cooler line started leaking at the quick-connect fitting on the rad. Then the lower one started seeping. The leaks gotten progressively worse, and now the engine oil cooler lines/fittings have started leaking too!

There are no O-Rings, the fittings have a ring of a hard, teflon-type plastic material on them. The connections are not what I would call solid, you can wiggle the lines where they enter the fittings.
Should I have replaced the spring clips when I did the job? (Hard for me to imagine that is the cause). Or does one need to replace all 4 cooler lines when replacing the radiator? (I sure hope not)... Any ideas, advice, or experiences to share?

Thanks in advance for any help!!

(If there were no quick disconnects, there would be no leaks. And if there were no plastic tank radiators, the original ones would last for 20 or more years! I know GM, Mopar & Ford all use this crap to reduce manufacturing costs, I hear the japanese cars have this stuff in them too). -Sigh...

Much too young to feel this damn old!!

[jdmccright]

No direct experience here (I did just replace my rad but I have the thankfully older threaded fittings), but typically for Teflon- or soft plastic-style gaskets, they should be replaced as well since they don't spring back once tightened down like rubber o-rings do. Once they are compressed, they deform and maintain their shape, especially after being heat-cycled so many times. Hope this helps!

[j cAT]

Originally Posted by Ol'Jim

Recently replaced the radiator on my truck, because one of the plastic tanks cracked. (I curse those things, as my 38 year old Monte Carlo still has the ORIGINAL rad in it!).
Rather than pull it & spend $160 to get 1 of the tanks replaced, I bought a complete new Napa replacement radiator. Easy enough to change out, but...
The unit has an engine oil cooler in the driver side tank, & a trans cooler in pass side tank.
All 4 fittings for the cooler lines are the quick-disconnect types, with a spring clip retainer in them.
I re-used the clips, and the lines. The female fittings on the radiator were new, (came with the new unit).
A couple weeks later, the upper trans cooler line started leaking at the quick-connect fitting on the rad. Then the lower one started seeping. The leaks gotten progressively worse, and now the engine oil cooler lines/fittings have started leaking too!

There are no O-Rings, the fittings have a ring of a hard, teflon-type plastic material on them. The connections are not what I would call solid, you can wiggle the lines where they enter the fittings.
Should I have replaced the spring clips when I did the job? (Hard for me to imagine that is the cause). Or does one need to replace all 4 cooler lines when replacing the radiator? (I sure hope not)... Any ideas, advice, or experiences to share?

Thanks in advance for any help!!



Much too young to feel this damn old!!

the lines must be fully seated,the lines moving are a sign that they are not fully seated....

you are instructed to fully seat these lines then the plastic ring is placed up against the fitting nut then the spring clip is rotated into the locked position ...then you pull out on the line to ensure it is locked ..securely..

since they all leak this must not have been done correctly....

[Ol'Jim]

Originally Posted by j cAT

the lines must be fully seated,the lines moving are a sign that they are not fully seated....

you are instructed to fully seat these lines then the plastic ring is placed up against the fitting nut then the spring clip is rotated into the locked position ...then you pull out on the line to ensure it is locked ..securely..

since they all leak this must not have been done correctly....

Guys, thanks for your input.

j cAT, you sounds knowledgeable about these quick-connect fittings.
The radiator did not come with any instructions, and I have no prior experience with these fittings. I used a spring hook tool to remove the clips, but I did not know they can/should be rotated to a certain position to lock them. I did tug on the lines to make sure they were connected and wouldn't pop off, but apparently I didn't do things correctly.
The Chilton's book is useless, I cannot find any reference to the connectors at all, they never give the details one needs. (Their standard is more like: "Disconnect all hoses & cooler lines, remove the radiator, replace the radiator, reconnect all lines & hoses")...
Can you possibly point me toward any publication or website that shows these fittings, or at least provides specific techniques for working with them?
(Or, can you please give me a bit more info? I am kind of slow, no idea how to rotate the clips into locking position, etc).
Thanks again,
-Jim.

[j cAT]

Originally Posted by Ol'Jim

Guys, thanks for your input.

j cAT, you sounds knowledgeable about these quick-connect fittings.
The radiator did not come with any instructions, and I have no prior experience with these fittings. I used a spring hook tool to remove the clips, but I did not know they can/should be rotated to a certain position to lock them. I did tug on the lines to make sure they were connected and wouldn't pop off, but apparently I didn't do things correctly.
The Chilton's book is useless, I cannot find any reference to the connectors at all, they never give the details one needs. (Their standard is more like: "Disconnect all hoses & cooler lines, remove the radiator, replace the radiator, reconnect all lines & hoses")...
Can you possibly point me toward any publication or website that shows these fittings, or at least provides specific techniques for working with them?
(Or, can you please give me a bit more info? I am kind of slow, no idea how to rotate the clips into locking position, etc).
Thanks again,
-Jim.

The oem manual is clear on the r/r of these lines..the U shaped locking spring is rotated into position so as to not bend the spring clip..with the line fully seated in you do this ,,,,,,,then after it is seated and locked you pull outward. this then should be secure,tight...the plasitic ring needs to be right up on that fitting nut...

[brcidd]

Heres is how I do it- put the clip in the ring holder then snap the lines into place- ....

Install a new retaining ring into each quick connector fitting.

Hook one of the open ends of the retaining ring in one of the slots in the quick connector.

Be sure to rotate the retaining ring around the connector until the retaining ring is positioned with all 3 ears through the 3 slots.

Ensure the 3 retaining ring ears can be seen from the inside of the connector and the retaining ring can move freely in the slots.

Install the line into the quick connector fitting until a click is heard or felt.

Pull back on lines to ensure a proper connection.

Snap the plastic cap onto the quick connect fitting.

Ensure that the plastic cap is fully seated against the fitting.

Hope this helps

[Ol'Jim]

After checking again, I am pretty sure I connected the fittings properly, (I have driven this truck over 2 thousand miles since the rad change, and the lines haven't popped out yet). I do think the aftermarket fittings are the cause of the leaks.
I figured new GM fittings might cure the problem.
The first GM dealer I called, asked for the last 8 characters of my VIN, saying they could tell exactly what components the truck came equipped with. They came up with 2 each of one Part No for the Trans cooler, 2 ea of another P/N for the Engine Oil Cooler. They were out of stock, so I asked for the 2 P/N's, and called some other Chevy stores.
2 other nearby dealers each had 1 of both P/N's, so I thought I could get the whole set between them.
Picked up 1 each at 1st place, then decided to ask the guy to double-check the P/N's.
He asked for the VIN also, and the EOC fittings came up the same, but he pulled a different P/N for the trans fitting.
It was a bit larger than the 1st P/N, and had a flat flange on it, (to go against the Rad), and an O-Ring on the threaded part of the fitting. The other P/N has no flange, no O-Ring, and looks to have a tapered compression-type end past the threads.
So I went out and looked under the hood, and the radiator has a different looking fitting than either of the ones the dealer came up with! (Thanks NAPA!). Not saying that neither of the OEM fittings will work, but I just need to take the thing apart in the morning, and see what comes out of it. My old OEM radiator is 500 miles away, I wish it was here, so I could rob those fittings off of it. I can ask a buddy to go pull them out & snap some pics to me by e-mail tomorrow, but now I don't even know if the OEM parts will fit in the Napa radiator! So I bought the 3rd P/N, (It was $27!). Figured I can always return the one(s) I don't need...
Thanks again for your help, have a great weekend.
I will post my findings once I get things taken apart.
-Jim.

[j cAT]

well ! you replaced the radiator , and did not compare new with old...
you bad....

[Ol'Jim]

UPDATE:
Thank you guys for your assistance with this issue.
Happy to report that simply replacing the fittings on the Napa replacement radiator, with genuine GM parts, solved the problem completely!
2500 miles since, and not a drop on the driveway!
A GM tech told me the aftermarket fittings from any source are a 50/50 shot at best, because they require a precision bore diameter to seal, and the Chinese stuff is dicey...
Thanks again! -Jim.

[j cAT]

Originally Posted by Ol'Jim

UPDATE:
Thank you guys for your assistance with this issue.
Happy to report that simply replacing the fittings on the Napa replacement radiator, with genuine GM parts, solved the problem completely!
2500 miles since, and not a drop on the driveway!
A GM tech told me the aftermarket fittings from any source are a 50/50 shot at best, because they require a precision bore diameter to seal, and the Chinese stuff is dicey...
Thanks again! -Jim.

thanks for this info...so the napa chinese radiators have defective fittings for the oil cooler lines....these chinese are making inferior products in all markets...best avoid this countries products if possible..

so NAPA was no help in resolving this ?