Antifreeze in engine oil.

[mightyarms]

I just put an lt1 motor in my s10, and ran it few times over the last 3 weeks, but it was leaking oil from the offset oil adaptor, so I had to replace the seal, when i went to empty the pan, it had antifreeze in the oil, the engine sat a while, but when I drained the original oil to change to the 4x4 pan it did not have any antifreeze in it. It is not smoking white or anything. I also had to remove and relocate the knock sensors, and antifreeze came out of the holes, so I put two plugs in place of them, one was an oil drain plug, and the other came of the back of the original 4.3l engine, which had about the same length threads as the oil plug, they were also about the same lenght as the knock sensor threads, so I used them, but now I wonder if they could have went too far into the block and cracked it, because i think the knock sensors might have some sort of taper to thier threads. I put a new filter and fresh oil in it, and plan on checking the oil again tomorow, after my exhaust is finished and I run it a few minutes. Any advice would be greatly appreciated, this has got me very worried after 4 months of work. I was hoping to have it on the road soon.

[Dave]

If you installed a sensor that is too long you might ckarcked a coolant port. You have to run it to find out. Did you hear anything odd when you tighted everything up?

[shea1]

Automatic or manual trans?



If it is auto have your radiator checked!!!



The radiator can develope a leake internally and let the antifreeze and oil mix. You should be able to tell by looking at the antifreeze.



Other than that it could be that the RTV sealant used around the coolant passageways didn\'t seal or maybe your head gasket is shot?



Where did you get the engine? Did you build it or have it rebuilt? If it is used from a junkyard or something I would suspect a head gasket, but the rediator is easiest to check so I would start there.

[mightyarms]

Thanks for the info, It is an auto, but the antifreeze is clean, and i have a brand new radiator from ebay that fits in the support. the engine was used out of a caprice, but when I drained the original oil it looked normal. I called my local napa machine shop, they said that the plug should not have cracked anything and that 90+% of motors with this problem it is an intake gasket and to try that first. I am trying that, for only $20 it is worth a try.

[mightyarms]

Oh yeah, it does not have an engine oil cooler, went with offset oil adaptor.

[TwiztedMods]

That would make me go crazy, I hate those type of problems!

[riotpolice75]

id get both the intake and head gaskets. better safe than sorry. check ebay for the gaskets. i just got a complete set of gm service parts gaskets for my motor off ebay for like $15.







smith

[ThreatResponse]

Hopefully this will help some,I would agree on the possible intake leak. Being that the oil returns in the head are usually very close to the water jackets. With the jackets being so close if a leak developes between the two, the oil is gravity feeding while the coolant is under pressure. This (most of the time)would allow the coolant to leak over to the oil return but not let the oil leak into the coolant, hence the possible reason why you have coolant in the oil pan and no oil in your cooling system. I would definetly keep that in mind, and whatever you do, don\'t run the motor before resolving this, coolant doesn\'t play well with engine parts! Hope this helps.

[riotpolice75]

2nd that







smith

[mightyarms]

thanks for the ideas, i replaced the intake manifold gaskets only to find that lt1 motors do not have coolant ports in them. But, it just hit me that when i was installing the pan I also pulled the knock sensors. the antifreeze was dripping down and I think some of it went into the pan since I was In the process of tightening down the bolts, and I was thinking that hardly any or none went in, but more than I thought must have ran along the block and seal into the engine, since I have not seen any more antifreeze in my oil. I shure feel dumb for not thinking more about this as I was installing the pan.