2eXceL

iTrader: (2)

My '96 LS400 has a small Coolant Leak from the Front Drain plug, the little hose that drains Coolant from the Radiator.
I had drained it and opened the valve last week and Re-filled it after changing out the Thermostat, but now it will leak.. small leaks every time I turn it on it will leak a small puddle from that location. I opened and re-tightened the plastic valve on the Drain plug and it still has not solved the issue, it's almost as if the valve is not closing completely and letting coolant leak out.

I am not sure what the issue is.. the Reservoir tank is not dropping level very much, so I know its a small leak.

Also when I refilled the Coolant I removed the Filler Plug in the Front of the engine.. the 17mm bolt, I read on the tutorials that there is a Gasket in that plug, so I am not sure if i miss-placed it or where it goes, since I do not see a gasket in there, so perhaps this is the reason I have the leak???
Does anyone have pictures of the gasket or can explain to me where it goes on the Filler Plug?
Any other suggestions about why I have this leak..
Thanks

etex

I'll address only the leak from the drain at the bottom of the radiator, as I don't remember whether there is a gasket at the filler plug.... On the drain plug, you have it too tight and the O-ring is no doubt damaged now. Catch the coolant in a clean bucket for re-use and remove the plug assembly from the bottom of the radiator. It just unscrews. There is an O-ring you will see when removed. Take the O-ring to an auto parts store and get a new one to match. Install in reverse order of removal.... Good Luck.

RA40

iTrader: (6)

Mine began leaking and after a spell, it becomes brittle and the gasket dry. Just get a new one and you'll be good.

jkweller

i agree same problem here just p/u a new one if that doesnt work a little trick i use when i was waiting for mine to come was .... i took some high heat plumbers tape and wrapped the the threads in that, not sure on long periods but it worked for two and a half weeks while i was waiting for mine

2eXceL

iTrader: (2)

Thanks I will try that first and see it it improves with a new O-Ring. I was also thinking I could use some hi temp plumbers tape, but if the O-ring is easy to find that would be best.

I will also hit up LexLS, since it was his Tutorial that describes the Gasket in the Filler Plug, I'm just not sure if there is a difference between Gen1 and Gen2. Anyone recently drain or fill their coolant on a Gen2?

2eXceL

iTrader: (2)

So I went to Autozone and picked up a set of random size universal O-rings to prep for the O-ring replacement on the Drain plug. I also re-inspected the top 17mm Filler Plug and then noticed the Gasket was already there and fine... never was lost.

I then removed the Drain plug from the bottom of the Car and it started making air gurgling sounds as the coolant drained, so I removed the Reservoir cap to let it drain fully. I inspected the O-ring and noticed it looked fine I did not see anything damaged or wrong with it. I decided to screw it back in before letting all the coolant drain. I then filled the system at the Filler Plug a few times and kept squeezing the hoses to remove Air. I then filled the Reservoir, started the Car and did not see any Coolant leaks.. it looks like the problem is gone. I am thinking maybe the coolant system had some air bubbles or the drain plug was not seated correctly. I made sure not to tighten it too much. Went on some test drives, filled the system after some Heater & AC cycling and now all is well. Kinda strange problem, but now Im just glad the problem is gone and no leaks.
For anyone draining the Coolant on a LS make sure you let some coolant run to remove air as you close up the Drain plug and of course inspect the O-ring in case it does need replacement.

PureDrifter

iTrader: (10)

lol common problem. repair manual calls for you to burp the coolant before putting the filler plug on the throttle body back on.