Need Information

[kerley]

I'm ready to install my Autometer Boost and Pyrometer Gages. I am concerned with the exhaust manifold drilling necessary to install the Pyrometer guage. The directions are all here and installation is no big deal but I do not trust myself with the drilling so I think it would be better to remove the exhaust manifold and have a Machine shop do the drilling and tapping of the threads, also I would know that there was no debris left to destroy the Turbo.

 

So my question. Is there any gaskets other than the Exhaust Manifold and the Flange gasket seal and is it necessary to disconnect the Turbo from the exhaust down pipe?

 

I know these are simple questions but I've never worked on a Cummins before and want to have all parts on hand so an easy project does not become a PITA.

 

Thanks guys.

[TFaoro]

There is NO NEED to take it off and take it to someone. The drilling and tapping is very easy and straight forward. Some leave the engine running so that the chips blow out as you drill it, but most just put a dab of grease on the bit then use a small magnet to take the chips out. When tapping do the exact same thing... Little bit of grease on the bit, tap it, then clean the chips out with a small magnet. I've drilled and tapped mine twice, my brothers once, and my neighbors. (None of them running)  

 

If you really have your heart set on removing the manifold you will need the gaskets between the head and manifold, the gasket between the manifold and the turbo, and the gasket for the oil return on the turbo. No gasket needed between the downpipe and turbo. 

[mulcher812]

Like TFAORO said it's very easy to drill and tap. Just remember it's a pipe tap not a standard thread style. So when using the tap only go about 1/3 of the way down the tap. This is because the threads are tapered. Then just use a magnet to clean any excess out.

[Ed ke6bnl]

when you say magnet are you dropping the magnet in the hole or keeping the tap magnetized.

[mulcher812]

With the grease the fragments fall straight down and stick to the inside. So just stick a small magnet in the hole and retrieve the rest.

[TFaoro]

I use a pen magnet to retrieve the shavings in the manifold

[Mopar1973Man]

Another way is to dip a q-tip in the manifold. The shavings get snagged up in the cotton q-tip.

[CSM]

Honestly, in my personal non professional opinion, as long as the chips are small, they will clear the housing.  Just don't break the bit off in there. 

If this was a problem, you'd read about a lot more shelled turbos. 

[MnTom]

Honestly, in my personal non professional opinion, as long as the chips are small, they will clear the housing.  Just don't break the bit off in there. 

If this was a problem, you'd read about a lot more shelled turbos. 

I concur. I have also been told by a reputable mechanic I know that the chips you get in the manifold are small enough that by time the turbo gets spinning when you first start it the chips are way past the turbo already.

[Mopar1973Man]

I tend to agree with both above posts...

[rancherman]

DO run the tap in a little further than 1/3. (but don't allow it to bottom out and break off!) The female threads need to be fully cut, the fitting is the tapered part, and you want to make sure the threads on the manifold are opened up far enough to engage several threads on the manifold.

[TFaoro]

DO run the tap in a little further than 1/3. (but don't allow it to bottom out and break off!) The female threads need to be fully cut, the fitting is the tapered part, and you want to make sure the threads on the manifold are opened up far enough to engage several threads on the manifold.

Actually both the fitting and the hole are tapered. At least I used a npt tap.

[rlane547]

Just take it a step at a time and go slow. You won't have any problems. They actually sell a product to put on your tap to trap all the debris. I've used it at the shop and I can't tell any difference whatsoever between using it and grease. I used grease many times when I had to heli-coil the spark plugs in the 2v 5.4L Fords and never had a problem. After you tap it you'll be surprised by just how little is left to get with the magnet or Q-tip.

[rancherman]

Actually both the fitting and the hole are tapered. At least I used a npt tap.

As long as the fitting can screw in more than a couple threads before it gets tight! Don't need to see a new post; "starter threads stripped out..now what???" :D

honestly, I'm more concerned with the tip of the sensor breaking off and destroying the turbine.. than a few chips of cast.

Cast tends to make pretty small chips, where steel will be more a long curly q.

[TFaoro]

As long as the fitting can screw in more than a couple threads before it gets tight! Don't need to see a new post; "starter threads stripped out..now what???" :D

honestly, I'm more concerned with the tip of the sensor breaking off and destroying the turbine.. than a few chips of cast.

Cast tends to make pretty small chips, where steel will be more a long curly q.

Valid point!! Although my egt probe has been 1600+ and hasn't melted off yet 

[rancherman]

I'm not 100 percent, but just plain ol breaking off 'was' the fear some years ago. The stingers didn't like a particular vibration when mounted in certain positions.. Don't hear much of that these days..

I was surprised when I mounted my Autometer electric.. they wanted the end of the stinger at least midway in the stream. That seemed like a heck of a lot of skinny *** thermocouple hanging in the breeze!

[Mopar1973Man]

Valid point!! Although my egt probe has been 1600+ and hasn't melted off yet 

 

I've been multiple trips over 1,400*F and my old DiPricol was holding together fine for 10 years.

 

 

Type K (chromel – alumel) is the most common general purpose thermocouple with a sensitivity of approximately 41 µV/°C (chromel positive relative to alumel when the junction temperature is higher than the reference temperature).^[9] It is inexpensive, and a wide variety of probes are available in its −200 °C to +1350 °C / -330 °F to +2460 °F range. Type K was specified at a time when metallurgy was less advanced than it is today, and consequently characteristics may vary considerably between samples. One of the constituent metals, nickel, is magnetic; a characteristic of thermocouples made with magnetic material is that they undergo a deviation in output when the material reaches its Curie point; this occurs for type K thermocouples at around 185 °C.

Type K thermocouples may be used up to 1260 °C in non-oxidizing or inert atmospheres without rapid aging. In marginally oxidizing atmospheres (such as carbon dioxide) between 800 °C–1050 °C, the chromel wire rapidly corrodes and becomes magnetic in a phenomenon known as "green rot"; this induces a large and permanent degradation of the thermocouple, causing the thermocouple to read too low if the corroded area is exposed to thermal gradient.^[10] Another source of drift in type K thermocouples is that near 400 °C, a slow reordering in the chromel wire occurs; this is reversible and leads to hysteresis between heating and cooling.

[CTcummins24V]

I got all the chips out with a shop vac.