16g Oil feed hole

[jahjahSQC]

So I've got 2 turbos. Turbo "A" is the turbo with shaft play that came with my car. Turbo "B" is the free turbo i recieved from the guy i originally bought the car from. Both are probably Ebay turbos. I doubt either is an MHI.

Turbo B's exhaust housing holes did not line up with the stock or aftermarket O2 housing, so i used Turbo A's exhaust housing. The dowel pin was too big on A's exhaust housing and it would have clocked the turbo off and the return line would have never bolted on, so i ground off the dowell and clocked the turbo so it would sit right. The problem i'm having now is that A had a stainless steel feed line that bolted just fine onto A's center section will not bolt into B's. The banjo bolt is too big. I was probably just gonna put a 90deg elbow in the turbo feed and do away with the banjo bolt completely.

So, couple questions...

-Is this a common thing among off-brand turbos?
-Anyone have an idea what size the thread might be? its not a std metric thread, so maybe NPT?

thanks to anyone who reads this and assists

 

[99gst_racer]

Yes, it is common for China stuff to have varying fit and minor changes compared to the part that they copied.

If it previously had a banjo fitting, then it's a straight thread and definitely not NPT. And if it's a straight thread, chances are it's metric. Measure the diameter of the hole with a set of dial calipers and report back.

 

[agentorange313]

Yes, it is common for China stuff to have varying fit and minor changes compared to the part that they copied.

If it previously had a banjo fitting, then it's a straight thread and definitely not NPT. And if it's a straight thread, chances are it's metric. Measure the diameter of the hole with a set of dial calipers and report back.

or get a metric thread pitch gauge

edit: just thought about this, the pitch gauge might not fit in the threaded hole if it has too small a diameter.

 

[jahjahSQC]

Yes, it is common for China stuff to have varying fit and minor changes compared to the part that they copied.

If it previously had a banjo fitting, then it's a straight thread and definitely not NPT. And if it's a straight thread, chances are it's metric. Measure the diameter of the hole with a set of dial calipers and report back.

Ok, good to know i'm not going mad.

Turbo B came with no fittings or anything. So i can't confirm that it had a banjo bolt in it or not. I do know that a 10x1.25 bolt would start to thread but would only catch the first maybe couple threads.

or get a metric thread pitch gauge

edit: just thought about this, the pitch gauge might not fit in the threaded hole if it has too small a diameter.

The pitch gauge does fit, but none of them seem to be a perfect fit. An M10 is very close, but a tap still cuts a slight bit.

 

[99gst_racer]

Maybe a thread pitch difference? Do you have any 1.00 or 1.50 10mm bolts to try?

 

[jahjahSQC]

sadly, i don't. I guess I might make a trip with the center housing to the hardware store and see what fits.

 

[agentorange313]

if they arent MHI turbos

they could be using any of the thread pitches

m10 x 1.0
1.25
1.5

 

[JusMX141]

Should be 12mm x 1.25 on the oil inlet. Even the Chinese tap their housings to this spec.

 

[turboglenn]

M10 will barely start into a 1/8npt, the turbo probably has a 1/8npt hole in it if it's a copy (or 1/8 bpt which is still close but without the taper)

the oil feed on the end of the head on our cars is m10 x 1.25, (oops brain fart might be m10 x 1.0) so make sure the banjo bolt is right at the head if you feed it there. the rest of our oil galleys and plugs are mostly 1/8th BPT but 1/8th NPT will tighten in and seal (i just had a 1/8 npt fitting on my head beside the turbo feed checking pressure about 20 minutes ago)