New radiator leaking fluid from upper transition line questions

[LegoSharks]

Title gives TLDR of current situation. I installed a new radiator yesterday, and while running the engine to cycle the new coolant through noticed that there was a leak of oil substance on the radiator. Now it went all the way from the top line so it's most likely that one. If anyone has any inkling as to what could be causing it to spray/drip/leak that would be greatly appreciated. For as far as I remembered, it clicked in properly when I put it in so not sure what would be causing it from that end. However while pulling it back out today, I noticed a yellow ring right before the lip portion of the hose. While I don't think it's supposed to have one, is there supposed to be a gasket there?

 

[Hey you]

I noticed an O ring inside the fitting attached to the radiator on my Tahoe, it was black, nothing yellow. Maybe the yellow
was a plug used for shipping?

 

[Foggy]

Is it trans lines or oil lines? Trans is on the right(pass) side of radiator
Oil Cooler lines on the left (driver) side ?
The actual fitting may not be seated into the the radiator itself on a new radiator.
You may want to remove the fitting and reseal it with some teflon paste..

 

[LegoSharks]

Its the transmission lines my tahoe dosent have the oil cooler lines. As for the fitting the new one came with them on as it has the new clips in em too

 

[LegoSharks]

Is it trans lines or oil lines? Trans is on the right(pass) side of radiator
Oil Cooler lines on the left (driver) side ?
The actual fitting may not be seated into the the radiator itself on a new radiator.
You may want to remove the fitting and reseal it with some teflon paste..

well tightening them EVEN further seems to have done the trick so far as its not spraying or leaking like how it was before so that's an improvement. Thanks for the suggestion cause frankly I would've never have thought that it needed to be tightened more.

 

[bill1013]

Title gives TLDR of current situation. I installed a new radiator yesterday, and while running the engine to cycle the new coolant through noticed that there was a leak of oil substance on the radiator. Now it went all the way from the top line so it's most likely that one. If anyone has any inkling as to what could be causing it to spray/drip/leak that would be greatly appreciated. For as far as I remembered, it clicked in properly when I put it in so not sure what would be causing it from that end. However while pulling it back out today, I noticed a yellow ring right before the lip portion of the hose. While I don't think it's supposed to have one, is there supposed to be a gasket there?

Lubing it up before insertion always helps…that’s what she told me.