Center mount turbo drain bolts

[SnowDrift]

What size are these bolts? I'll need to make or buy a block-off plate since I'm using the side mount turbo on my engine and it was originally equipped with a center mounted turbo. Dealership said they are M10x1.5 - does that sound correct? What sort of length will I need for them for those of you who have done the same thing? 25mm-30mm or so?

 

[MrMarty51]

How thick is the block off plate that You will be using ?
Just a guess, maybe about 3/4 of an inch longer than the thickness of the plate.
Ease the bolts in without the plate and make sure that they will not bottom out in their bores.
Also You might make the block off plate thick enough that a hole for the oil feed could be threaded into the cover plate then use that to feed oil to Your turbo.
Maybe about 3/4 inch thick should be enough threads to seal a NPT fitting with some thread tape on it.

 

[dbrannon79]

@Will can tell you for sure since he is a hummer guy.

Now just a suggestion... if you plan to install a oil catch can, this might be an ideal place to connect the drain for it! Here is one of the fake copies of the provent 200 but has a screen mesh filter. you can get the real filters to fit it.

https://www.amazon.com/dp/B07HKBRZ2K

 

[Will L.]

The actual turbo mounting bolts would be too long. The turbo housing they go through is thick.
Afaik there is no factory block off plate. Or matching bolts for that use.

Get bolts that barely bottom out (or can’t quite) without anything in place.

I would use a piece of 1” (1/8” thick) or 1.5” if needed -angle iron. Cut to length and mill or use sanding belt to true one surface. Drill the two mounting holes. Use the factory oring for the turbo seal. Then just bolt it down.

The reason for angle iron instead of flat steel is: the vertical part of the angle will keep it from flexing, keeping full clamp force of the seal.


I would not try draining pro vent in because that drains directly onto the camshaft. It wasn’t the smartest place to drain the turbo.

 

[MrMarty51]

How thick is the block off plate that You will be using ?
Just a guess, maybe about 3/4 of an inch longer than the thickness of the plate.
Ease the bolts in without the plate and make sure that they will not bottom out in their bores.
Also You might make the block off plate thick enough that a hole for the oil feed could be threaded into the cover plate then use that to feed oil to Your turbo.
Maybe about 3/4 inch thick should be enough threads to seal a NPT fitting with some thread tape on it.

Oh boy. I was thinking this would be the oil pressure Feed to the turbo.
Please disregard the above posting.

 

[Will L.]

It is an oil pressure feed also. This is the turbo oil seal- aka the figure 8 oring.
The small side is the oil supply and large is the drain.

 

[dbrannon79]

anyone have a pic of where this is on the engine? I would wonder if there is enough meat there to tap some threads and use a couple of pipe plugs.

 

[Will L.]

I don’t think you can enlarge the holes to a normal size where you can tap npt threads in those two without them hitting each other.

 

[SnowDrift]

Or...

One moment, please...

Center Turbo Oil Drain Blockoff Plate

This custom S plate is used to block off the oil ports on a 6.5L center turbo style engine block when the ports are not needed. Fits GM, GEP, IHI Navistar, and P400 center-mount turbo engine blocks as pictured. We go over the top on these, cut from 7075 T6 aluminum. They are no longer etched...

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