getting pipe plug for pyrometer out of ATS turbo housing

[1 FMF]

I may be getting a pyrometer for my truck. The turbo on it has to be at least 5 years old. The exhaust housing of the turbo is a cast iron piece, and is a rough, rusted red color.
The housing has a threaded hole for the thermocouple, but because the previous owner never installed one when he had the kit installed there is a pipe plug in the hole. It's a 1/4 NPT I think, and the plug is also iron, and the same color as the rest of the housing. I've tried to remove the plug with the right size wrench, and adjustable, and vice grips but didn't have any luck. I'm worried about cracking the housing or wrecking the threads. Any tips? I'm not sure if I should try removing the plug after running the engine hard to get the housing real hot, or hit it with the acetylene torch, or both. And I don't want to buy the pyro until I know I can get that plug out, otherwise I have to buy a thermocouple that gets threaded/weleded into the exhaust pipe.

[ December 27, 2004, 10:25 PM: Message edited by: 1 FMF ]

 

[labman]

Find my best techniques along with some great ideas from others. http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=24;t=000035#000000
www.answerway.com/browse.php?category=568&pgtitle=Other+Internet

 

[labman]

Sorry about that irrelevant second link I accidently posted above.

 

[Pablo]

Have you tried all the standard "juices" (ie PB Blaster? Kroil? etc?)

 

[Pablo]

For rusted in tapered bung plugs, I find a small ball peen hammer rat-a-tat-tat, rat-a-tat-tat, rat-a-tat-tat really fast but not super hard will set a frequency that will break the rust bonds.....then hit it with the juice and wax and other methods....

Too bad no antisieze was used.

 

[Gary Allan]

Does the pyrometer have to be RIGHT THERE? Can't you just weld a "weld-a-let" on the exhaust pipe a few inches further down stream and then bushing it down for the thermal couple???

Just wondering

 

[1 FMF]

no it doesn't have to be there, but
I just had new exhaust made up and installed. The pipe coming off the exhaust manifolds come together into a Y casting which feeds the turbo. If I install it on this feed pipe, the only accessible place to drill and clamp or weld the TC is where the pipe runs under the engine. Doing it this way will only read the temp of exh. gasses from the driver side manifold and won't see any of the pass. side. So I am hoping to put it in the turbo, where they designed it to go, and where I know what the temps should stay below.
The guy that did the exhaust said he clamped on to the existing down pipe (exit side of turbo) and ran new 3" pipe all the way out the back. I had wanted the muffler removed. He said the down pipe looked press fit into the turbo, and didn't want to mess with it, possibly hurting the turbo housing.

if someone can host a jpg for me, I can post the system schematic. My image hosting place is down.

 

[1 FMF]

here it is, any ideas let me know.
Have pb blaster on the plug again, will try removing tomorrow.