Leaking antifreeze, but not overheating...

[cji4130]

My 06 M35x has just about 99300 miles on it...runs like a dream. the other day my father informed me that its leaking antifreeze. there is a definite leak but not excessive...small puddles have been accumulating but the reservoir tank has remained just under the minimum line and have not changed since Friday..car is not overheating(to my knowledge, the temperature gauge is pointed a slightly below the center, isnt that where its supposed to be?), Air conditioner also works fine. to be safe i already ordered a silla radiator, they seem to have gotten good reviews, anyone have experience with them? i will be doing this fix myself. I must say im somewhat nervous.. currently worried about 2 things. i see that there are 2 A/T lines connected to the rad that have to be swapped, how much A/T fluid will i be losing during the swap, anything to be worried about? also ive heard after swapping the radiator people run into overheating problems and need to replace the thermostat...? anyone else run into radiator problems on your M's, what should i expect...please chime in and help a brother out!

[svard75]

Wow. Why replace the rad if there's a small leak a d you don't even know where it's from. Take the lower engine cover off and the front intake remove the rad cap and use a coolant pressure tester. Check the level inside and fill to top. Then pressurize the system to about 15 psi. Use a light and look around for the leak. If nothing shows or it's a very slow leak you can get special dye to put into your cooling system then use a uv light to see where it's coming from.

Removing the rad has so many risks associated including accidentally breaking the AC lines.

[cji4130]

Wow. Why replace the rad if there's a small leak a d you don't even know where it's from. Take the lower engine cover off and the front intake remove the rad cap and use a coolant pressure tester. Check the level inside and fill to top. Then pressurize the system to about 15 psi. Use a light and look around for the leak. If nothing shows or it's a very slow leak you can get special dye to put into your cooling system then use a uv light to see where it's coming from.

Removing the rad has so many risks associated including accidentally breaking the AC lines.

because my dad is a jerkoff and said to just replace the whole rad....it was only $115. it appears to be leaking along the top..so im pretty sure the whole thing needed to be replaced anyway. i also dont have one of those coolant pressure testers. how likely is it to break one of these AC lines?

[atlM35]

Like already mentioned, it might be a good idea to determine where the leak is coming from before ordering parts. The UV dye kits are available at auto parts stores. It might be something as simple as a cracked hose or loose clamp.
Removing air from the system is key when working on the cooling system.

[atlM35]

Just saw your reply. If the leak is visible on the top of the radiator, replacing it is a good idea. If any lines crack during install, they were already on their way out and needed replacing anyway.
If there is no overheating right now, your thermostat is probably fine. Most of the overheating after an install is from not completely burping the system.
You'll lose minimal transmission fluid if you quickly cap off the hoses.
Good luck. It's really not too bad, just time consuming.

[svard75]

Wow. Why replace the rad if there's a small leak a d you don't even know where it's from. Take the lower engine cover off and the front intake remove the rad cap and use a coolant pressure tester. Check the level inside and fill to top. Then pressurize the system to about 15 psi. Use a light and look around for the leak. If nothing shows or it's a very slow leak you can get special dye to put into your cooling system then use a uv light to see where it's coming from.

Removing the rad has so many risks associated including accidentally breaking the AC lines.

because my dad is a jerkoff and said to just replace the whole rad....it was only $115. it appears to be leaking along the top..so im pretty sure the whole thing needed to be replaced anyway. i also dont have one of those coolant pressure testers. how likely is it to break one of these AC lines?

Hey sorry if I made you upset. If my dad offered advice I would take it provided he has the experience with the specific topic. I'm sure you would as well. I typically google my issues and find the average consensus around an issue then use my own judgement and perhaps even talk to a couple of shops before biting the bullet. It's generally easier to address the issue if you properly diagnose the issue instead of assuming a part failure. It could even be something as simple as the radiator cap seal or the upper hose.

If you want I can upload the process for diagnosing a leak from alldatadiy.com.

[cji4130]

car finally overheated last friday...ordered a silla radiator from ebay. was a direct drop in fit...installed, filled with fresh coolant...and all is well, leak is gone and car is running cool as a cucumber....=) to anyone whose curious, radiator job on this car is tit.