3406E head/liner question

Liner orings....

 

My old engine would use 1 gallon a month with a very slight antifreeze smell sometimes. I had the oil sampled a few times over the years that were inconclusive. At the end it started running hot even with a new rad. When it spun a rod bearing at one million miles we took the engine apart and discovered a slight crack in the head along with the rest of the damage. I'm assuming the crack would open up when hot and burned up the antifreeze clean enough not to contaminate the oil.

 

I know it has probably been said already but my 6nz was doing exactly what you say yours is doing.After dropping the pan thinking i might have rolled an o-ring when i inframed the motor i pressurized the system and put a large piece of cardboard under it and let it sit for a day.Turned out i found a little bit of coolant running down the front timing cover and it was the water pump.Truck never overheated but just had a little bit of steam coming from the blow bye tube with a few drips of water coming from it.The seal between the oil side and coolant side of the pump was letting coolant pass and as soon as it hit the pan was being vaporized and coming out the tube.when it hit the colder air near the bottom of the tube it was turning back to liquid.Keep in mind mine was only doing this when the engine was up to temp and had been running about an hour.Hope this helps you.