OIl drain plug -- return feed line?

[_asquared]

I picked up this ESi-T for a steal of a deal this weekend and there were a few things wrong with it. I fixed some of the issues and I discovered that the oil return line from the turbo is in the spot of the drain plug.... I've never seen/heard of this before. Should I be looking to weld a proper bung immediately or can I wait until I swap the new motor with a proper bung (a few weeks)? If this is harmful I'll be getting at it soon.. otherwise I'll just wait.

 

[project_tsi]

Fix that, now.

You want your turbo's oil drain to be as high on the pan as possible, that way, it drains back into the oil.

Having it drain into the pan's drain bolt location is just causing the oil to back up into the turbo. It will cause restrictions and ruin the turbo seals.

 

[illeffekt vr-4]

It will cause restrictions and ruin the turbo seals.

If it was like that for a while then it could already be messed up. Fix it asap and go from there.

 

[RSTeclipse97]

Fix it now not good. I actually got my fitting from a hydrolic shop. It was a 90 degree barb fitting threaded on one end. Drilled hole in pan and there was a rubber oring on each side of the pan just tightened the nut but not to tight works like a dream and cost less than the cra pyou can get on ebay

 

[_asquared]

well I'll be fixing that tonight then.. I'm pretty sure thats the cause of the small amount of oil coming out of the compressor...

I planned on rebuilding the turbo this week so its a good thing I got that straightend out before reinstalling it.

 

[Defiant]

Explain to me how this oil will "back up". It'll be the height of the oil in the sump. There's no where near enough oil draining out of the turbo to back up in a half-inch line.

 

[VelocitàPaola]

Explain to me how this oil will "back up". It'll be the height of the oil in the sump. There's no where near enough oil draining out of the turbo to back up in a half-inch line.

Well the oil drain plug is on the bottom of the pan and points downward. If it were to be used as a return point from the turbocharger, several fittings (adapters, elbows, etc.) would undoubtedly be necessary. Considering the above mentioned orientation of the drain plug, in conjunction with any fittings, the lowest point of the return line would now be below the lowest point of the oil pan. As we all know, the oil drains in turbochargers are gravity driven, so if the lowest point in the return line is the lowest point in the pan, oil will start to back up. That'd be my guess...

 

[Locke]

While I will recommend placing the turbo drain bung higher up on the pan, I am going to agree with Guy here in that it shouldn't back up. Given the drain is of adequate size, the oil wont rest at a level in the drain any higher than it sits in the pan.

Assuming the possibility of awkward bends and such, consider a P or S-trap in a conventional waste plumbing system. In this case, the fluid level is well above the level in the sump, but as more fluid is added than the trap can hold, it just overflows into the rest of the waste system.

This assumes a drain line big enough, and that you are not running oil the consistency of molasses.

This makes sense, yeah?

 

[VelocitàPaola]

This makes sense, yeah?

In theory, but it neglects siphoning effects, crankcase pressure differentials, etc.. Plus, I disagree with Guy's assessment that the oil draining from a standard journal bearing turbocharger can't back up a -8/0.5" drain; especially with all of those bends introduced by the necessary fittings to connect to the drain plug.

 

[Locke]

Assuming he is using -AN sized line and fittings, then there will be no size constrictions to cause problems, only sharp bends to potentially limit flow in this sense. I would argue, though, that if crankcase pressures were high enough to back oil up all the way to the turbo (keeping in mind the positive pressure at the inlet and the system being sealed until the sump) then he one would have greater problems to worry about.

But I suppose this is all moot.

With my very limited experience with turbo-systems, I will respectfully back down. It's not much my place to dissent here. Please note that regardless of my thoughts mentioned in this thread, it is my opinion that optimally the drain line would be large, free of unnecessary bends, and dumping above the fluid in the pan, following convention.