View Full Version : 4bd1 Turbo drain dilemma
County3.9
22nd May 2010, 03:17 PM
I pulled off the oval plate (below the exhaust manif) today thinking it was going to be easy to drill a hole in it for the turbo drain...but no! It's a machined assembly designed to hold the shaft of the oil pump, not just a flat plate!! Does anyone have any pictures or a detailed explanation of how the hole is to be drilled? The problems I can think of are...
1. Drilling a hole above the shaft won’t allow enough oil to flow down past the shaft
2 Drilling to the side (offseting from the centre of the plate) will weaken the assembly (not to mention the difficulty of getting it right)
https://www.aulro.com/afvb/images/imported/2010/05/573.jpg
The plate
https://www.aulro.com/afvb/images/imported/2010/05/574.jpg
The hole it came from
Any help is appreciated!!
THE 109
22nd May 2010, 05:59 PM
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
County3.9
22nd May 2010, 06:02 PM
https://www.aulro.com/afvb/images/imported/2010/05/570.jpg
I was thinking of plumbing the fitting into these plates instead. Pros/Cons?
https://www.aulro.com/afvb/images/imported/2010/05/571.jpg
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)
Bearman
22nd May 2010, 07:48 PM
https://www.aulro.com/afvb/images/imported/2010/05/570.jpg
I was thinking of plumbing the fitting into these plates instead. Pros/Cons?
https://www.aulro.com/afvb/images/imported/2010/05/571.jpg
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
County3.9
22nd May 2010, 08:05 PM
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-landy-enthusiasts-section/44549-4bd1t-set-oil-drain-etc.html )when using the ALT return pipe so I thought that might not be the way to go.
Bearman
22nd May 2010, 08:28 PM
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.
Dougal
23rd May 2010, 08:04 AM
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.
lambrover
23rd May 2010, 01:20 PM
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 109
23rd May 2010, 06:22 PM
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
isuzurover
24th May 2010, 12:40 AM
...
http://i124.photobucket.com/albums/p29/isuzurover/LR_PICS/July-Aug-08-inc-turbo-conv014.jpg
http://www.aulro.com/afvb/isuzu-landy-enthusiasts-section/63176-budget-4bd1-turbo-install.html
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