Turbo Oil Return

[Anonymous]

Any good ideas of where to place the oil return from a turbocharger? I know I could route it to the top/side of the oil pan, but would rather return it to the block. Could return it into the fuel pump hole since it won't have a pump in it, but that is on the other side from the turbo. The turbo itself will sit above the 2V manifold so everything is downhill from there but it doesn't seem right to route it to the other side of the motor. Any ideas or is the pan my only route?

 

[Anonymous]

I used the pan.

 

[Thad]

Oilpan is usual, alternate could be side cover at lifter gallery.

 

[rbohm]

8) oil pan is the best as it keeps the drain line on a proper downward slope to prevent oil backing up.

 

[StrangeRanger]

But it has to enter the pan ABOVE the oil level. Any backpressure in the line can kill the turbo. For that reason, the cover plate on the lifter galley is a good spot as is the timing cover.

 

[addo]

Uno problemo, guys... There be no side plates on a small six.

I wonder about the road draught tube hole (if the block is so equipped) - you would then use a PCV type valve cover.

Cheers, Adam.

 

[Anlushac11]

8)

On my 2.3L turbo there is a pad cast into the side of the block above the oilpan on the passenger side that is drilled and tapped right above the oilpan rail. The oil return line runs into there and just dumps into the oilpan. Be very careful where you drill but you should be able to drill a hole in the skirt of the block above the oilpan and tap it for whatever size you need.

 

[StrangeRanger]

Uno problemo, guys... There be no side plates on a small six.

I wonder about the road draught tube hole (if the block is so equipped) - you would then use a PCV type valve cover.

Cheers, Adam.

Is there room on the timing cover?

 

[CoupeBoy]

The turbo itself will sit above the 2V manifold so everything is downhill from there but it doesn't seem right to route it to the other side of the motor. Any ideas or is the pan my only route?

High enough to route the oil back into the valve cover itself?

ron

 

[StrangeRanger]

The oil in the return line is a froth. MacInnes describes it as looking like black shaving cream. the 2 rules for routing the return line are:

1) The oil flow must always be downhill. Flow will simply stall if there is any uphill flow to the line at all.

2) The oil must return at a point higher than the oil level in the pan. If the return port were submerged flow would again stall due to the head of the oil in the sump which it cannot overcome.

Any location that satisfies both of these rules is OK.

 

[XFlow_Fairlane]

I would punch a hole between two of the pan bolts 2-3" down and weld a NPT bung on. the cheapest and simplest way to go. then use a section of AL hard line bent up (.5" or larger) off the turbo itself and then have a barb fitting on the pan end and use a short length of rubber/silicon hose to hook it up.


nick

 

[rbohm]

8) you could always runt he outlet to the opposite end of the oilpan from the sump. keep it about an inch to 1 1/2" about the pan floor. that should provide unrestricted flow, and will help in removing the air from the oil as it returns to the sump.

 

[StrangeRanger]

I think i'd still try to tap into the side of the timing cover. Not just because it's a whole lot closer than the top of the sump but also because there would be absolutely zero chance of submerging the line outlet. I doubt the motion of chains and sprockets would do much to de-aereate the oil froth but they would surely benefit from the extra lubrication.

 

[Anonymous]

I will look into the timing cover route, and look realistically at routing to the other side of the engine (250 block) at the fuel pump boss or where the road draft tube would be (not so equipped here). Don't think it would be a good idea to tap into the side of the block because there isn't much room due to the crankshaft counterweights and they would froth the oil even more. Didn't mention that I wanted to avoid the oil pan because this is going into a Bronco and the fewer things hanging down near the ground, the better. This won't be a rock crawler, but it will go offroad-- dunes mostly....

 

[XFlow_Fairlane]

well the line shouldn't hang down low at all. should always be a downhill slope. a bung near the top of the pan that is aimed up would work best. good luck on the timing cover since there isn't too much meat there to tap into. I would put a bung on the pan and baffle the pan at the same time. I would not be too concerned with oil frothing in the pan, the oil slung off the crank will knock it down with ease. the oil lines on a turbo are very critical if you want it to live ling. if this thing is gonig off road then I would try to take the shortest straightest route possible or else you might run into trouble on hillls.

nick

 

[SuperMag]

I'm not familiar with this particular block, but many blocks are single wall thickness just above the oil pan flange (water jackets only come down as low as the bottom of the cylinders). Would it be possible to drill and tap a hole in the block here?

 

[Anonymous]

Super, that was what I was getting at about the crankshaft clearances being very tight there. I think oil might possibly be returned onto the crankshaft causing more of a frothing problem as the crank whips it more.

 

[SuperMag]

What's the clearance towards either end? Room enough to put a deflector or elbow of some kind inside the block that would direct the oil downward?

I personally wouldn't worry too much about oil getting on the crank. The oil coming through that return line is going to be minor (think of the bearing clearances in the turbo) and there's all kinds of oil falling on it from above, sloshed onto the crank from dune jumping etc, and the whole bit will look like a whirling wad of taffy anyway...

I'll be quiet now...

 

[Anonymous]

On the 300-6 directly behind the motor mounts on both sides is a 5/8" freeze plug. From what I have heard, this actually was designed as a turbo oil return. I would assume the 240 is the same way, it is the same block after all. The one on the left hand side is immedietely in front of the oil pump, so I was planning on opening this up a bit, and using it for the inlet on my dry-sump system. My only concern is with the pressure side of the oil. Should I run a high-volume pump, or is this to risky? I have had very bad luck with them before. I intend to open up some of the oil passages, are there any areas I need to watch? Where should the oil for the turbos come from?

Jared

 

[StrangeRanger]

On the 300-6 directly behind the motor mounts on both sides is a 5/8" freeze plug.

I'm a little confused here. Freeze plugs are in the water system, not the oil galleys. Looking at my 96, the only holes I see in that area are a pipe plug on each side of the block, they appear to be a 3/8" NPT but I'm too lazy to pull one to measure it. The one on the left is in the distributor mounting boss and appears to plug the end of the cross-drilled galley that supplies oil to the distributor shaft and bushings. I wouldn't mess with that one on a bet. The one on the right is immediately below the freeze plugs on that side of the block at the very bottom of the water jacket, it is not down in the skirt area of the block. Without pulling it to find out, I'd guess it only goes into the water jacket, not all the way through. I'd guess it's there for installation of a drain petcock in industrial applications. Am I missing something or is your block that different from mine?