Coolant spraying from rear of engine.

[brendan310]

About two months ago, I noticed my temp gauge shooting up. I turned on the heater, pulled over and noticed a small amount of steam from the rear of the engine. I let the car cool off for a few hours, checked my radiator level and it was a little low. Filled it up. No smoke or overheating since then. I have checked underneath the car and the fluid level semi-daily since then and haven’t had to add any fluid.

Today (in 90 degree heat) I drove down to Autozone to pick up some coolant(prestone rebate) and when I got home i see smoke/steam under the hood. I pop the hood and see coolant spraying from the rear of the engine. I had to close the hood as it was getting on my front fender. Any ideas besides the heater hose?

Here are the pics:
http://www.flickr.com/photos/58607920@N07/sets/72157626922912415/

 

[mattd]

pics dont work. Is this the car in your sig?

 

[MrCritical]

I got the pics to work, but I can't really see anything. Maybe add dye to coolant? Is there a freeze plug back there?

 

[brendan310]

Thanks for the replies. Yes this is a 1998 Diamante. Known for heater core o ring problems. The pics probably don't add much as it seems to be a pinhole leak somewhere.

 

[brendan310]

Good idea on the dye. I have some on hand for engine oil leaks. Think this would be harmful to a cooling system?

 

[HTSS_TR]

If you didn't change all the heater hoses, it's time to change now. My LS400 had coolant leak near the rear of the engine about 6-7 years ago, it was 2 of 4-5 small heater/coolant hoses had some small cracks. Before that my Accord had a leak in 1 of its heater hoses too.

 

[ComfyShorts]

I wish there was a tool that would put the cooling system under pressure so you could see where the leak is at....oh wait

 

[MarkM66]

Originally Posted By: ComfyShorts
I wish there was a tool that would put the cooling system under pressure so you could see where the leak is at....oh wait

 

[scott37300]

Originally Posted By: brendan310
Good idea on the dye. I have some on hand for engine oil leaks. Think this would be harmful to a cooling system?


NO, they make a dye for cooling systems, one for "green" and one for extended life coolant.

Like the posts above you can buy a coolant pressure tester and pressurize the system and it should spray out of your pin hole leak and show you exactly where it is. You MIGHT even be able to rent one of these from a parts store.

 

[mechtech2]

Originally Posted By: ComfyShorts
I wish there was a tool that would put the cooling system under pressure so you could see where the leak is at....oh wait

 

[brendan310]

It was only the heater hose. Thanks for your help.