Thread: 4bd1 Turbo drain dilemma

The drain on the factory turbo engines are at least 1/2",probably bigger as I haven't measured it.To get a large enough hole through the plate I would start at the centre and drill on an angle to miss the cam gear.Try to go as big as possible to let the oil flow unrestricted.Or you could use the alternater vacuum pump oil return port aswell,tee off from the turbo and go to both if you need to.

Eric

I was thinking of plumbing the fitting into these plates instead. Pros/Cons?



This is the oil feed line. I cut the dome off the existing fitting and tig welded on a flared fitting for the oil line(It has a cap on it in this photo)

Originally Posted by County3.9

I was thinking of plumbing the fitting into these plates instead. Pros/Cons?



This is the oil feed line. I cut the dome off the existing fitting and tig welded on a flared fitting for the oil line(It has a cap on it in this photo)

Just in front of the domed fitting you are referring to is a normal rubber drain hose from the vacuum pump on the alternator. If you put a T-piece in this you could plumb the turbo drain into it. It will not drain if you plumb into the pressure line arrowed...Brian
Sorry mate, cocked that up a bit, I didn't read it properly. I now realize what you said. That fitting will be fine for the oil feed and use the vacuum pump drain for the return....Brian

Originally Posted by Bearman

Just in front of the domed fitting you are referring to is a normal rubber drain hose from the vacuum pump on the alternator. If you put a T-piece in this you could plumb the turbo drain into it. It will not drain if you plumb into the pressure line arrowed...Brian

Hey Brian, JUSTINC talks about a flooding issue( http://www.aulro.com/afvb/isuzu-land...drain-etc.html )when using the ALT return pipe so I thought that might not be the way to go.

OK, I wasnt aware of that issue, I didn't think there would be oil flow to cause flooding. If your motor doesnt have the smaller oval plate like the turbo motor (some seem to have them and some don't) you could always oxy a pipe into the sump for the return immediately below the turbo. It has to be above the sump oil level or draining may not be efficient.

Interesting, my oil pump drive cover is just a flat plate (4BD1T) and the oil pump drive gear below it sits higher than yours does.

You'll need a bigger oil drain than the alternator vacuum pump has. Turbo drains don't just pass oil, they pass exhaust and compressor air that bypasses the seals. That's why the drain is about 10x bigger dia than the oil feed line. Go into either the cam cover plates or drill/tap into the block.

Remember in my emails saying about the drain it was a pain, I pretty sure I drilled a 1/2 inch hole it can be done on mine the circumfrence of the hole is between the O ring recess and the stepped shaft housing for that gear drive, it was tight but can be done

The stepped cover plate is used with the gear style oil pump where as the flat plate is for the other type(can't remember the name).The drive gear is different for each pump aswell.

Eric