So I am finally going to drill and tap for a egt probe this week. My question is should I start the truck or just let er rip and use a pen magent after I get the hole drilled?  Wouldn't running the truck suck the shavings instead of blowing them out the hole?  Just wondering what's my best plan of action as to not cost myself more later?  I don't want to take the turbo off because I am sure the bolts will be wonderful to take off. 

 

Here's where mine is drilled...

 turbo was off so I can't be any help with the filings

While the running the engine will blow out the chips, drilling on top of a hot ,vibrating engine did not appeal to me. Here's what I did. My hole is where @015point9's diagram shows. I drilled my pilot hole almost but not quite through. Then the tap drill the same way. Now 90% of the chips are already cut before you break through. You have a little less the 1/4" to work with. Then I greased the drill bit and put my shop vac spout right at the hole and drilled the rest of the way through. I greased the tap also and ran the vac to catch all chips that I could. When done I stuck a pencil magnet in the hole like you mentioned and fished around. Very few chips got caught. This worked well for me.

Very good idea!!! Awesome idea. Thanks y'all! 

Drilled mine with cold engine but running and greased drill bit, got everything ready then started it, took no time at all maybe 2 or 3 minutes, didn't even melt the grease. Exhaust back pressure blows the chips out no problem

 

Edited April 28, 20204 yr by wil440

Same here... Did i twice. Once for the EGT gauge and once for Quadzilla probe. Cold and used grease for both the drill and tap. 

13 hours ago, Mopar1973Man said:

Same here... Did i twice. Once for the EGT gauge and once for Quadzilla probe. Cold and used grease for both the drill and tap. 

Running or naw?  I should just do it and stop overthinking it lol.

Couple of things to add

1. I very lightly centre dotted where I needed to be to give the drill some help on starting

2. I'd suggest making sure the drill you use is sharp but preferrably not been resharpened or at least resharpened in a machine and not by hand. It is very difficult to get the point centred when sharpening by hand, if it's off centred it will drill bigger. Truck running btw

Measured while off and cold.  Drilled while cold but running...no grease.  Started with real small pilot bit so that each following bit had constant air flow passing around it.  Smaller increment bit increases so all shavings remained very small and light and easily blown out.  Easy as pie. 

I drilled my hole most of the way through then started engine and completed hole. Shut engine off and cut threads with greased tap. Very easy process. 

I drilled mine with the turbo off. Shoved a rag in the exhaust manifold, drilled the hole, then pulled the rag out. I did have the turbo off for another reason than just drilling the hole.

Gonna do this tomorrow. Drill it most the way start the truck and drill the rest of the way.  Thanks everyone! 

So I got it installed today. However when I started drilling either I moved the bit off the hole or I had it leaned over a little.  I removed a little extra material from the side of the hole that I didn't need to. I went and ahead drilled the hole and installed the probe. Everything else went smoothly.  Y'all think this is something to worry with or naw?  No exhaust leak or anything as of now.  I tried to post a picture but I can't from my phone.

Edited May 2, 20204 yr by Unreal Summit

If the tap bit ok and actually tapped threads it will be fine, I used a little exhaust paste on mine to complete the seal

 

no leaky no problem

Edited May 2, 20204 yr by wil440

Yeah it taped perfect. Had a bunch of threads. The fitting got tight and looked good.  Just worried me having extra material beside it removed.  I don't want it to crack or start leaking later on.  

Not a big deal then.  To be honest my first one I drilled wasn't perfectly centered either...but it never leaked and always performed flawlessly so no biggie. 

Awesome! I think it will be just fine like it is too!