(The correct drill for the 1/8 NPT is not a numerical drill, use the proper "R" drill)


HUH I don't queit get what you are saying here.

Thanks! Usta

 

Sorry, upersleder, but that was funny!

 

Did anyone else have a b!+$# of a time getting the four turbo-manifold nuts off? I couldnt get the top 2, then before I really leaned into them, I decided to try the bottom ones. I could hardly get a wrench on them. Don't know how I'm gonna convince those 2 off
So I'm soaking them overnight in PBlaster. Anyone got any tips? I'm now considering tapping the probe hole without removing the turbo

 

I did mine just like shovelhead did...

Have a buddy hold a vacuum clean hose next to the drill bit. Also used grease on the drill bit.

We didn't have a magnet to pick shaving... But he showed me a trick with a Q-Tip... It works good in a pinch. With a strond shop light I couldn't see any chips in the hole.

During tapping also use a good quantity of grease on the tap. Also check you hole for burrs and chips in the bottom again...

Works good on mine... 800-900*F on a good 6% at 45 MPH... Only seen 1100*F Once!

 

Those two bottom nuts can be fun at best. I use a box end wrench on the rear one and hit it with a hammer to break it loose. It's hard to get a good hit on the wrench but it does work. On the front one I use an extension and a torque extender (looks like a crows foot only longer and has a boxed end) that I bought just for that purpose. You can also remove it with a socket, extension, and a universal joint, or an end wrench from the bottom side. They will also come off easier if they are warm. Just be careful not to get too close to the exhaust housing without a glove on.

HTH
Max

 

Get a set of "S" shaped, or curved handle wreches.
They've come in very handy on many occasions.

 

When I did mine I went to cummins and bought the whole schnagety of parts, gaskets studs nuts the whole show, I ended up changing the gasket between the turbo and exh. without removing anything but the nuts, I did try to pull the studs but to no avail, with just the nuts off I was able to pull the gasket off two studs at a time, and yes the nuts are tough to break loose, just hold the flanges apart with your wrench and put a piece of cardboard/formica/flashing/duct tape/something over the turbo inlet, it cost me $2.66 to replace the gasket, I returned the other $24 in hardware. as for anti sieze it might not survive the heat, and on a gas rig it is a no no as it goofs the o2 sensor

 

Thanks. I believe the FSM says to use anit-seize when reinstalling.

 

OK, so I went ahead and drilled/tapped the hole, without removing the turbo. Knock on wood that I got most of the debris out, and hope the rest gets blown out the tailpipe.

Anyways, one note that should be added is NOT to forget your safety glasses...of course we always wear them when using a drill , but when drilling into a pressurized manifold, you might get metal-chips in your eye I wouldnt know anything about that

 

I have been on this board since the first year it was up and I never once heard of anyone trashing a turbo from drilling a hole. In fact I have never heard of one being trashed and after taking one apart, there are no close gaps between the exhaust fins and the housing.

On one of my 92 series Detroits, a common thing to happen is for the fire rings to break up and spit out the exhaust. I rebuilt the engine and the turbo had some chips from passing the rings under power. I ran the turbo that way with new bearings for over 200,000 miles and then finally changed it out. Matter of fact the old turbo is still in the downstairs archives.

I think all this with grease and removing the turbo for some cast iron chips is way overkill. The turbo is not that close fit to worry about it. The chips are going to blow out as soon as it is started. On cast iron it is just small chips not long curley chips like with regular steele. There is not enough mass there to hurt turbo blades. It they were, carbon blowing out would also tear up blades.

 

I drilled the pyro probe hole without taking the turbo off. Never had a problem since. I dunno, though, may have had something to do with the fact that I replaced the turbo the following day....

 

I've seen two turbos trashed by chips but it could have been avoided if the owners hadn't continued driving with the turbo locked up till the impellor warped.
After that I started removing the turbo while drilling and tapping for quite some time mainly because it's easier than grease and magnets. But after thinking on this for awhile I've come to an easier conclusion and have used it on the last three installs with success.
Leave the turbo on, no grease or magnets, then start the engine after drilling and tapping with the intake hose off the turbo so you can watch it. On two of the trucks I did no problem, but on the third the turbo never started spinning. All I did is shut it down and turn the turbo backwards by hand to clear the clips, started it again and everything was fine.
I will continue use this method. Soooo easy.

 

Just a FYI...

You have to think of your turbo as a big heatsink. When you have your pryo mounted pre-turbo you can't use it to judge your cool down time.