My chevy s-10 2000 93k miles has had a minor leak on I think a transmission cooler line (solid metal line) where it meets the radiator, for years, but i got home last night and had the front compartment outgassing steam. Opened the radiator, had nothing in it.

Looked today, ive 3 hoses going in same side of radiator: engine return, transmission cooler line, and I think something with the AC system (its a metal to rubber line).

Filled halfway up this morning, drove it a bit, was stable for the most part. Outgassing still. After I filled it completely getting back, didnt see any major leaks, maybe a slow drip at one spot (cant tell accurately with all the rain).

Does this sound like a bad radiator, bad hose, or something else (water pump maybe)? Checked oil, its not getting into the engine.

8/6/2011 12:54:11 PM

The radiator should have inlets and outlets for the secondary coolers on both sides, one for transmission and one for engine oil. I haven't had a problem with any of those lines, but I did replace the radiator because the solder joints had started to crack and leak.

Those motors had a bad run of head gaskets that basically degraded from contact with the dex-cool. The engine will sometimes consume coolant, other times it will present as an external leak, and you may or may not see it in the oil. Mine was an external leak and didn't show up in the oil, but I put some stop-leak in there for a couple days and it kinda sealed itself up. I haven't had to add coolant for a while, but the real fix is to replace the head gasket and/or replace the Dex-cool. I have the gasket set, but it's been sitting for about 10 months because I'm too lazy to tear the top end apart.

http://www.handymanlyness.com/archives/auto/repair/engine_mech/intake_manifold/GM_truck/gasket_replace_99_Jimmy.html

http://d-tips.com/general/articles/article.aspx?id=3

http://www.automotiveforums.com/vbulletin/t892880.html

[Edited on August 6, 2011 at 7:06 PM. Reason : links]

8/6/2011 7:03:45 PM

System was flushed about 3 months ago. I also put some stopleak in about a month ago, didn't do anything.

Had a good look I think its the engine return hose as its slow leaking when full and I'm loosing more now watching when its running.

Thanks for the other info thoough ill have a look at it.

8/6/2011 7:33:38 PM