++++++++++It's coolant, not oil! +++++++++++++ HELP

So this setp is in my older Vette but since I find great help on TPI here I am bouncing it off you guys...

I have a brand new L31 long block married to a TPI with the Scoggin Dickey base intake. It fired right up, but began to run worse and I noticed that I am spitting oil and white smoek from the exhuast.

I did make one dumb mistake, but I am not sure how it could cause the problem. I had NO vent on the valve cover at the L31 cap was not vented like my last engine, which means I had a huge vacuum....

I took the top back apart to check things out and inspect the manifolf seal. Compression seems to be fine. It appeared #8 was the main source of the leak and a little in #6, based on looking at the plugs. There did not appear to be any oil in the PCV lin, plenum, or runners. I have to pull the manifold tonight after draining some coolant before I can see in the intake portion of the heads.

Anybody got any ideas?
Thanks, Mark

 

I should note the oil was mainly on the passenger side, with only a bit on the driver's side. I do have an H-pipe in the system right under the pain so it leads me to believe the problem is only on the even-cylinder side...

 

could be a problem with the build. call the place you got it from and start complaining and demanding they fix it (if it came with a warranty)

 

It's a GM crate long block from Jeg's, so while that is possilbe I'm sure hoping it is very unlikely.

I'm really trying to see if anyone knows if the huge amount of vacuum could have caused an issue...

 

i could see a large amount of vacuum managing to pull oil through the valve stems past the seals, but it would have stopped once you fixed the vacuum issue.

 

I haven't ru it since I added the proper vent- I will remove and reinstall the manifold over the next night or two - I sure hope that's it..!

 

bad seals will let oil down the valve stem on deceleration when the vacuum raises. so i guess its possible that a large amount of vacuum could so the same thing to a good seal.

 

It's not oil, it's coolant!!!

 

Ouch. Coolant can only come from a few places- none of them good. If you can't find it with a real good visual inspection you might have to pressure-test it to find the leak (coolant dye that light up under a UV light can be very helpful finding tricky leaks like from small cracks in castings and weepy gaskets).

For now, follow your plan and re-do the intake seating. Drive it around and keep an eye on the oil and coolant levels, as well as the breather for a while, even if the problem seems to be fixed at the tailpipe.