neilly
Well-Known Member
Sorry mate I don't know. I have ongoing turbo problems, but I've been focusing on the return pipe. I may, at some point, try a pressure regulator on the inlet, so I may need to know those threads myself!
I've got a spare core in the garage and I've tried an M11x1.5 tap in to the inlet thread. It screws in no bother, but is too slack. So, it may be right and it might be an imperial 7/16 BSF thread?
The return pipe bolts to the core with two M8x1.25 bolts (I've just tested one of those bolts in the core) It wouldn't surprise me if LR used two different thread forms on the same unit! Sorry I can't be of more help.
EDIT
I haven't got a spare inlet pipe to measure.
No probs, cheers.
Here is a pic of the return pipe supplied by Turbo Technic (Allisport).
It's much larger than the standard.
It bolts to the turbo/core with the same interface (you can see the gasket) albeit with 2 x M6 bolts and to the block/sump with the silicon hose between two spigots.
The 3 studs and nuts are for the exhaust downpipe.
You'd need a lot of crankcase pressure to stop oil flowing down that.
Here is a pic of the return pipe supplied by Turbo Technic (Allisport).
It's much larger than the standard.
It bolts to the turbo/core with the same interface (you can see the gasket) albeit with 2 x M6 bolts and to the block/sump with the silicon hose between two spigots.
The 3 studs and nuts are for the exhaust downpipe.
You'd need a lot of crankcase pressure to stop oil flowing down that.
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Cheers Mick. I did make my own return pipe up using a bigger diameter silicone hose, fitted it, but decided not to actually run the Landy with it on. Bottled it because I had posts saying the silicone wouldn't handle the temperatures. However, I also thought the diameter of the fitting into the block is fixed, so even of you make the pipe bigger, it'll just back up from there.
Are you having turbo problems or just making your own pipes up?
I can't imagine that the silicone wouldn't handle the temperatures, I have a silicone elbow off the turbo output, that gas is a lot hotter than the oil flowing back to the engine ?
The pipe I have is a consistent diameter from the output of the core, through the spigot, down the pipe and into the block. The pipe is perhaps 1mm larger in diameter, I will measure it tomorrow.
If anything i'd guess the standard outlet pipe is smaller (AN6 v AN8 ?).
Yes, I am have turbo problems, not oil related like yours, mine started with a screaming Garret which I swapped for a high quality, hand built, Turborebuild.co.uk unit, which turns out to be completely unsuitable for a 300tdi - although not in thier opinion - in mine, my defender owning friends and two proffesional Land Rover garages ...
https://www.landyzone.co.uk/land-rover/300tdi-turbo-pickup.372916/
https://www.landyzone.co.uk/land-rover/300tdi-setup-tuning.373994/
I can't remember exactly the temp rating of the pipe I bought, but it wasn't a lot more than needed. I decided it wasn't worth the risk of it dumping all of the oil out. I found a genuine LR return online. Turbo still not right though.
Sorry to hear your power issue isn't sorted. It's a right pain when things drag on.
I always thought engine oil temp was the same as the thermostst tem (ie 88C).
It is a pain and has been compounded by Turborebuild's attitude (ie that their turbo is fine so it must be me).
