I'm away from the service manual and my notes. Anyone have the torque spec on the oil checkvalves installed on the turbocharger? The check valve is M12x1.5 steel into steel. I'm thinking 18ft.lbs (23NM)

Thx...

 

 

Must be one of those values not listed anywhere. Oil inlet line on the turbocharger is the oil line fitting that goes into the aluminum top of the check valve. 23NM should work for the check valve with the copper crust washer.

 

I'm impressed you guys torque everything!

 

I'd just snug it up by feel

 

More important on a high horsepower, high speed track car.... Especially an oil line.

 

it's a solid steel check valve assembly going into the cast housing, feel can be your friend vs a set value...oil line nuts are more sensitive

 

The Tial checkvalve bodies are aluminum and it's 11mm v. 12mm for the OEM steel check valve (see pic below). You have to be extremely careful torquing those as the aluminum is very easy to strip and you have to do it by feel as no number is published by Tial. At the same time they have a tendency to leak if night tightened enough so it's a fine line to thread. I was just curious as to the value on the OEM check valve, that's all. As pointed out above, they're steel so they can handle a lot.

I've always hated the Tial 11mm aluminum check valves due to their fragile design. With that said, I discussed the issue with the Tial engineers and they agreed to redesign the check valve inserts on the Xona turbocharger center cartridge so that the OEM 12mm steel check valves can be used in place of the Tial 11mm aluminum ones. They just sent me the new fittings and I'm in the process of retrofitting both sets of my XR1000s to the OEM check valves. I just did my brand new XR1000 spares at home and still need to do the ones that are on my car which I plan to do tomorrow. It sucks that I have to pull the turbos off the car to do this but worth it long term. About 3hrs of labor.

OEM 12mm on the left , Tial 11mm on the right. Note the Tial threaded insert at the base of each check valve.

 

glad they are changing design, was problematic

 

The Tial check valves were required for use on the Tial Garret turbochargers in the past because the check valve body had the restriction for the oil flow built in as the Garret center cartridge did not. The new Xonas have the flow restrictor built into the center cartridge and as such the old Tial check valves are no longer needed. They just had to go and machine new inserts for the OEM check valves and I suspect all the Xona coming out of the factory will be set up with them. Good to see companies willing to listen to feedback and improve their products.

 

Got the check valves on the XR1000s swapped over to OEM units. Took about 8 hours start to finish as both turbochargers had to come off to swap out the center cartridge steel inserts the check valves thread into. Torque setting of 30NM (22ft.lb) worked out perfect with the OEM copper crush washer. Test ran the engine with the car on the lift to get everything nice and hot and the bothersome oil leaks on the Tial check valves are gone, dry as a bone. Nice to get that resolved.

 

Just happened to stumble on this and happy I did. Any cost to you for the new adapters @powdrhound?

Regardless, looks like I should reach out to Tial about these. The XR1000s I received last month did not come with the adapters set up for the OEM check valves.

 

No cost. Two of my other friends have been having issues also with the Tial check valves leaking and I believe when I brought it to Tial’s attention they were very accommodating in getting this done. I would imagine the new OEM check valve inserts will be installed on all the XR1000s going forward.

With that said, if you haven’t installed the turbochargers it’s probably easiest to call Tial and sent the turbos back to them so they can swap the inserts out for you. It requires a special 7 sided tool to do this and I have no idea why they designed it this way vs doing a normal hex. There is a very slight mod that you have to do on the drivers side to clearance the OEM check valve as it’s larger up top. You have to grind down the head of the bracket bolt which is easy with a bench grinder. You can see this in post #11.

 

Thanks for s@powderhound.

Did Tial send you that adapter so you could remove the inserts, or did you machine yourself? Clearancing work is simple enough.

 

They were very accommodating and shipped me the adapter tool to borrow as I was in a bind with the check valve leaking on my right turbocharger that was on my car and I needed it swapped ASAP. I am actually shipping the tool back to them today. I've been running Tial turbos for a number of years now and have really been very happy with their service. Thumbs up!

Honestly, if you still have the turbos in the box, I would just send them to Tial and they will get them turned around and back to you in a few days.

Interestingly, we put the Tial check valves under a microscope to look at the sealing surfaces to see why they were leaking. Nothing jumped out at us but I would guess the mating surfaces were not perfect and would not seal at the 7 bar of oil pressure required. Looking carefully, the turbocharger male insert sealing surface does appear to be slightly concave (instead of a flat cone) which may be a contributing factor.

Check valve side - female



Turbocharger insert - male