Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

Any thoughts?

Wayne D.

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

If the engine is running, I'd expect the turbo to be hot enough to dull
your tools, apart from being most hazardous to work on.
My employer does engine conversions: we left an engine running overnight
on the dynamometer: someone slipped in & took a picture in the dark. The
turbo & exhaust manifold were red hot! I still have a copy of that photo.
Me, I'd bit the bullet & take thing off, work on it at the bench like a
gentleman.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out.

Wayne D.

The method I use to retap spark plug holes (for inserts) might be
applicable here, at least for the tapping part of the job. In COLD
conditions, smear grease onto tap. Then just cut a bit of thread, remove
tap and clean off metal dust/swarf. Reapply some more grease and repeat.
Done this a few times and the engines survived, even though it's not a
guaranteed method, as it's feasible some debris could still fall into
cylinder.

But if it's comfortable enough working on a running supercharger, that
sounds pretty safe, as far as avoiding iron dust in the engine. Manifold
pressure ought to be positive at all times, right? Vibration an issue?

Jordan

On Fri, 25 Apr 2008 18:57:13 -0500, David R Brooks
wrote:

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

If the engine is running, I'd expect the turbo to be hot enough to dull
your tools, apart from being most hazardous to work on.
My employer does engine conversions: we left an engine running overnight
on the dynamometer: someone slipped in & took a picture in the dark. The
turbo & exhaust manifold were red hot! I still have a copy of that photo.
Me, I'd bit the bullet & take thing off, work on it at the bench like a
gentleman.

I think I'd feel most comfortable with it removed. I'd just have to work
up the patience (oxymoron) to do it.

Wayne D.



--
Wayne D.

On Fri, 25 Apr 2008 19:00:33 -0500, Jordan
wrote:

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out.
Wayne D.

The method I use to retap spark plug holes (for inserts) might be
applicable here, at least for the tapping part of the job. In COLD
conditions, smear grease onto tap. Then just cut a bit of thread, remove
tap and clean off metal dust/swarf. Reapply some more grease and repeat.
Done this a few times and the engines survived, even though it's not a
guaranteed method, as it's feasible some debris could still fall into
cylinder.

But if it's comfortable enough working on a running supercharger, that
sounds pretty safe, as far as avoiding iron dust in the engine. Manifold
pressure ought to be positive at all times, right? Vibration an issue?

Jordan

They said vibration shouldn't be an issue.

Wayne D.

Wayne wrote:

On Fri, 25 Apr 2008 18:57:13 -0500, David R Brooks
wrote:

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

If the engine is running, I'd expect the turbo to be hot enough to dull
your tools, apart from being most hazardous to work on.
My employer does engine conversions: we left an engine running overnight
on the dynamometer: someone slipped in & took a picture in the dark. The
turbo & exhaust manifold were red hot! I still have a copy of that photo.
Me, I'd bit the bullet & take thing off, work on it at the bench like a
gentleman.

I think I'd feel most comfortable with it removed. I'd just have to work
up the patience (oxymoron) to do it.

I would presume you immediately do the drilling after starting from a
cold start. The turbo should take a lot longer than the few minutes
drilling would take to get hot enough to be an issue, particularly
sitting at idle.

I would personally be more comfortable working up to the tap drill size
in a few steps than drilling that relatively large hole in one shot. At
least starting with a center drill for a pilot hole and starting taper
would be good.

I would get the tap and tap drill as a quality set if possible. For
sealing I'd think a light coat of a suitable high temp gasket maker
would be good.

"Wayne" wrote in message
news
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

Any thoughts?

Wayne D.

Since it's post-turbo, the only issue you'd have would be getting the swarf
caught in your engine's muffler or catalytic converter.

If you're trying to work on it when it's hot you'll have to consider the
change in hole/thread dimensions caused by thermal expansion.

If I were you, I'd take a good look at just how difficult it'd be to get the
turbo off and, as you stated, do the job with your mill.

Otherwise, I'd see if it'd be possible to pull the plumbing off the turbo's
exhaust and stuff a rag in the hole to catch the swarf.

If I were to be installing an EGT sensor on my Cummins I'd go pre-turbo and
go through the exhaust manifold so as to have a better idea of just _when_
the turbo was about to get fried. grin

Wayne wrote:
On Fri, 25 Apr 2008 18:57:13 -0500, David R Brooks
wrote:

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

I think I'd feel most comfortable with it removed. I'd just have to work
up the patience (oxymoron) to do it.

Wayne D.



This is downstream from the turbine housing correct? If so just coat the
bit with heavy grease to catch most of the chips. Then do the same with
the tap. Step drill it so you get a nice hole. Any swarf you lose into
the hole will just get blown downstream into the catalytic converter and
not be a problem. This is a common thing to do when you add EGT sensors
or do an EFI conversion and need to drill the manifold or the head pipe.
I wold make VERY sure of the turbines position before you drill, some
of them extend down a bit into the outer end of the scroll.

--
Steve W.
Near Cooperstown, New York

Life is not like a box of chocolates
it's more like a jar of jalapenos-
what you do today could burn your ass tomorrow!

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

Any thoughts?

Wayne D.

I'd save the removal grief & do this underhood. I'd probably use a total
of 3 different sized drill bits. Put a ring magnet like those in
speakers around the proposed hole to catch the swarf. You'd only allow a
very minimal amount of dust in your system.

On Apr 25, 7:44*pm, Wayne wrote:

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.


Wayne D.

No need to have the hole perfect. Also no great worries about tapping
hot and having the hole/threads change size when cool.

Why not? It's a tapered pipe thread. If 7/16" is the right drill
for that thread (and I don't have a chart handy), the large end of the
taper will be cut to greater than that. As to the hot vs. cool size,
just let the cast iron cool down before you install the part. It
won't thread in as deeply as it would have into a hot casting, but
that's all. If that's a problem, thread it deeper cold.

John Martin

On Fri, 25 Apr 2008 20:40:57 -0500, Steve W. wrote:

Wayne wrote:
On Fri, 25 Apr 2008 18:57:13 -0500, David R Brooks
wrote:

Wayne wrote:
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.
I think I'd feel most comfortable with it removed. I'd just have to
work
up the patience (oxymoron) to do it.
Wayne D.


This is downstream from the turbine housing correct? If so just coat the
bit with heavy grease to catch most of the chips. Then do the same with
the tap. Step drill it so you get a nice hole. Any swarf you lose into
the hole will just get blown downstream into the catalytic converter and
not be a problem. This is a common thing to do when you add EGT sensors
or do an EFI conversion and need to drill the manifold or the head pipe.
I wold make VERY sure of the turbines position before you drill, some
of them extend down a bit into the outer end of the scroll.


I don't actually have the directions yet, just the info the sales person
gave me. I'll get that in the middle of next week. So I don't know if it
goes in pre or post turbo. Just looking at it, it would appear to go right
on the turbo housing just where the it connects to the exhaust manifold.
I'd have to guess that the exhaust coming out of the main pushes down on
the blades, then turns and goes to the back of the truck. The scroll
is in front of that. How some of it works is starting to make sense.

Thanks, I'll have to check that I don't hit anything on the inside.

Wayne D.

On Fri, 25 Apr 2008 19:52:19 -0500, RAM³
wrote:

"Wayne" wrote in message
news
Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

Any thoughts?

Wayne D.

Since it's post-turbo, the only issue you'd have would be getting the
swarf
caught in your engine's muffler or catalytic converter.

If you're trying to work on it when it's hot you'll have to consider the
change in hole/thread dimensions caused by thermal expansion.

If I were you, I'd take a good look at just how difficult it'd be to get
the
turbo off and, as you stated, do the job with your mill.

Otherwise, I'd see if it'd be possible to pull the plumbing off the
turbo's
exhaust and stuff a rag in the hole to catch the swarf.

If I were to be installing an EGT sensor on my Cummins I'd go pre-turbo
and
go through the exhaust manifold so as to have a better idea of just
_when_
the turbo was about to get fried. grin

How'd you know this was a Cummins? Looks like 4 bolts off of the exhaust
manifold, a clamp in front and back. 2 of the bolts are in the back and
have to be gotten from underneath. They said removing is difficult only
because of accessability. They probabaly mounted the turbo prior to
putting the exhaust manifold.


Wayne D.

How'd you know this was a Cummins? Looks like 4 bolts off of the exhaust
manifold, a clamp in front and back. 2 of the bolts are in the back and
have to be gotten from underneath. They said removing is difficult only
because of accessability. They probabaly mounted the turbo prior to
putting the exhaust manifold.


Wayne D.

however hard it is, it can't be harder than removing the turbo from an Audi
TT - that was a real total absolue (place curse word here) nightmare -
daughter broke a timing belt - well OK, we can fix that - just pull the
head - but to get the head off you gotta remove manifold to turbo bolts and
one stripped (don't ask, removing the head is non-trivial - a motor mount
goes through the middle of the timing belt, for example) - anyway, I cut the
bolt with a air driven cutoff and got the head off, and then was so tired
that when I went to unscrew the bolt it unscrewed easily and then I dropped
it right into the turbo where no amount of fishing with a magnet would get
it out (turns out it isn't magnetic, but I didn't realize that at the
time) - taking the turbo out (with the head off) took about 2 1/2 hours -
with the head in place I just can't imagine how long and how difficult it
would be - and putting it back was worse - there is no room, the
transmisison for all wheel drive is underneath it, and there are oil AND
water lines (2 of each) going into it, plus a mounting bracket that you
can't see and have to unscrew by feel, plus ....

so, trust me - don't do what I did..... and be glad you have more
accessability than on the TT.


** Posted from http://www.teranews.com **

Wayne wrote in
news
How'd you know this was a Cummins? Looks like 4 bolts off of the exhaust
manifold, a clamp in front and back. 2 of the bolts are in the back and
have to be gotten from underneath. They said removing is difficult only
because of accessability. They probabaly mounted the turbo prior to
putting the exhaust manifold.

I drive an '03.5 RAM 3500 with the 305/555 HO CTD. Grin

If you're *not* a member of the TDR site/fora then I'd strongly suggest
that you visit their site: http://www.turbodieselregister.com and browse
through the fora that apply to your model.

Their quarterly magazine is full of good technical advice on all aspects of
the care and BOMBing of the Cummins ISB engines.

For the benefit of those unaware of the term, BOMB is an acronym for
"Better Off Modified, Baby!".

When a Cummins is BOMBed, especially for towing, an Exhaust Gas Temperature
gauge is extremely highly recommended lest you fry the turbocharger.

See? It's an elementary exercise in Logic. grin

While my preference is for a pre-turbo installation, a post-turbo
installation offers the advantage that any dust/swarf would simply be blown
out the exhaust pipe since it would not pass through the turbocharger.

Those with catalytic converters and/or particulate filters might have an
issue with "stuff" collecting there so, if yours has either or both,
disconnecting the exhaust pipe at the turbocharger before starting the
engine and letting it run for a couple of minutes will be a simple step to
clear the deritus. The pipe can, then, be re-attached as soon as it's cool
enough to handle.

BTW, while you're installing the EGT sensor and gauge, why not also install
a Boost sensor and gauge as well? GRIN

Just 2 comments:
1. In my experience, cast iron DOES "powder" when cut.

2. If you haven't tapped with a pipe tap before, just be sure to test
the hole as you tap it, so you don't tap too deep. I don't know the
exact specs on the holes, but some fittings vary in actual size. If you
tap too deep, the fitting can bottom out before it seals well.

Pete Stanaitis
--------------------

Wayne wrote:

Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.

I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.

Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.

I have to get a tap since I don't have one that size.
I assume HSS will be ok?

It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.

Any thoughts?

Wayne D.

On Sun, 27 Apr 2008 14:45:33 -0500, RAM³
wrote:

Wayne wrote in
news
How'd you know this was a Cummins? Looks like 4 bolts off of the exhaust
manifold, a clamp in front and back. 2 of the bolts are in the back and
have to be gotten from underneath. They said removing is difficult only
because of accessability. They probabaly mounted the turbo prior to
putting the exhaust manifold.

I drive an '03.5 RAM 3500 with the 305/555 HO CTD. Grin

If you're *not* a member of the TDR site/fora then I'd strongly suggest
that you visit their site: http://www.turbodieselregister.com and
browse
through the fora that apply to your model.

Their quarterly magazine is full of good technical advice on all aspects
of
the care and BOMBing of the Cummins ISB engines.

For the benefit of those unaware of the term, BOMB is an acronym for
"Better Off Modified, Baby!".

When a Cummins is BOMBed, especially for towing, an Exhaust Gas
Temperature
gauge is extremely highly recommended lest you fry the turbocharger.

See? It's an elementary exercise in Logic. grin

While my preference is for a pre-turbo installation, a post-turbo
installation offers the advantage that any dust/swarf would simply be
blown
out the exhaust pipe since it would not pass through the turbocharger.

Those with catalytic converters and/or particulate filters might have an
issue with "stuff" collecting there so, if yours has either or both,
disconnecting the exhaust pipe at the turbocharger before starting the
engine and letting it run for a couple of minutes will be a simple step
to
clear the deritus. The pipe can, then, be re-attached as soon as it's
cool
enough to handle.

BTW, while you're installing the EGT sensor and gauge, why not also
install
a Boost sensor and gauge as well? GRIN


I may look those up later. I'm getting what Banks recommended for
what I'm towing. The sensor is going to go wherever their directions
say. Diesels are new to me, but I've been learning.
I got the last of the (not ultra) low sulpher engines.

Methinks I'll get an automotive shop to do the removal/installation.
I'll do the drilling/tapping

Wayne D.

Good to have verification on #1.
Haven't done any pipe taper tapping yet. So how deep to tap is a
concern for me. I'm not sure how tight the fit should be until
the shoulder hits. I'll practice with some scrap AL first.
I don't think I have any cast iron around (old water pump or whatever).

Wayne D.

On Mon, 28 Apr 2008 09:50:33 -0500, spaco
wrote:

Just 2 comments:
1. In my experience, cast iron DOES "powder" when cut.

2. If you haven't tapped with a pipe tap before, just be sure to test
the hole as you tap it, so you don't tap too deep. I don't know the
exact specs on the holes, but some fittings vary in actual size. If you
tap too deep, the fitting can bottom out before it seals well.

Pete Stanaitis
--------------------

Wayne wrote:

Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.
Any thoughts?
Wayne D.



--
Wayne D.

Wayne wrote in
news
On Sun, 27 Apr 2008 14:45:33 -0500, RAM³
wrote:

Wayne wrote in
news
How'd you know this was a Cummins? Looks like 4 bolts off of the
exhaust manifold, a clamp in front and back. 2 of the bolts are in
the back and have to be gotten from underneath. They said removing
is difficult only because of accessability. They probabaly mounted
the turbo prior to putting the exhaust manifold.

I drive an '03.5 RAM 3500 with the 305/555 HO CTD. Grin

If you're *not* a member of the TDR site/fora then I'd strongly
suggest that you visit their site:
http://www.turbodieselregister.com and browse
through the fora that apply to your model.

Their quarterly magazine is full of good technical advice on all
aspects of
the care and BOMBing of the Cummins ISB engines.

For the benefit of those unaware of the term, BOMB is an acronym for
"Better Off Modified, Baby!".

When a Cummins is BOMBed, especially for towing, an Exhaust Gas
Temperature
gauge is extremely highly recommended lest you fry the turbocharger.

See? It's an elementary exercise in Logic. grin

While my preference is for a pre-turbo installation, a post-turbo
installation offers the advantage that any dust/swarf would simply be
blown
out the exhaust pipe since it would not pass through the
turbocharger.

Those with catalytic converters and/or particulate filters might have
an issue with "stuff" collecting there so, if yours has either or
both, disconnecting the exhaust pipe at the turbocharger before
starting the engine and letting it run for a couple of minutes will
be a simple step to
clear the deritus. The pipe can, then, be re-attached as soon as it's
cool
enough to handle.

BTW, while you're installing the EGT sensor and gauge, why not also
install
a Boost sensor and gauge as well? GRIN


I may look those up later. I'm getting what Banks recommended for
what I'm towing. The sensor is going to go wherever their directions
say. Diesels are new to me, but I've been learning.
I got the last of the (not ultra) low sulpher engines.

Methinks I'll get an automotive shop to do the removal/installation.
I'll do the drilling/tapping

Wayne D.


You might want to have them do the drilling/tapping while they're at it.

That way, if something goes _wrong_, it'll be _their_ expense for the
replacement part(s). grin

FWIW, the Banks package is both overrated and overpriced - especially
when one considers that a "programmer" can provide the same (or better)
results for a fraction of the co$t and have the advantage that when you
take it in for warranty work you can simply reload the OEM programming.
This becomes important when a "fix" involves "flash"ing the Engine
Control Module [aka engine computer]. This way, when the technician looks
at the programming it'll be pure stock.

Re-programming only takes a few minutes and doesn't involve any hardware.

Tapping cast iron is not too difficult, especially if you are using sharp
tools. One thing you might want to consider is to do it on the vehicle,
cold with the engine off. You can rig compressed air to flow in to the tail
pipe and that way the air pressure will blow the swarf out.

You can loosen something along the way to allow a little pressure to escape.
I think about 10 to 15 PSI should do the trick without blowing anything.


--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.


"Wayne" wrote in message
news
Good to have verification on #1.
Haven't done any pipe taper tapping yet. So how deep to tap is a
concern for me. I'm not sure how tight the fit should be until
the shoulder hits. I'll practice with some scrap AL first.
I don't think I have any cast iron around (old water pump or whatever).

Wayne D.

On Mon, 28 Apr 2008 09:50:33 -0500, spaco
wrote:

Just 2 comments:
1. In my experience, cast iron DOES "powder" when cut.

2. If you haven't tapped with a pipe tap before, just be sure to test
the hole as you tap it, so you don't tap too deep. I don't know the
exact specs on the holes, but some fittings vary in actual size. If you
tap too deep, the fitting can bottom out before it seals well.

Pete Stanaitis
--------------------

Wayne wrote:

Since I'm going to be tapping into a big buck part and don't
really have any experience tapping cast iron, I figure I'll
just ask a few stupid questions.
I'm tapping a 1/4 NPT hole into the exhaust section of a
turbocharger. An EGT sensor will be put in there. The part
is cast iron, about 1/4 thick. The directions are to remove
the turbocharger, drill a 7/16 hole, then tap. The part
that screws into the hole has a shoulder which is
supposed to rest against the turbocharger.
Alternately they say I can drill and tap the hole
with the engine running. Once the drill bit goes
goes through, the exhaust pressure is supposed to
push any particles out. When drilling cast iron
they say it is supposed to turn to dust. I'd
be drilling from the top down.
I have to get a tap since I don't have one that size.
I assume HSS will be ok?
It's supposed to be a pain to get the turbocharger out.
But if it was out, I could finish the hole with a
7/16 HSS end mill. That I think, would give me a more
round hole than drilling by hand under the hood.
So I would think it would seal better that way.
Any thoughts?
Wayne D.



--
Wayne D.

On Tue, 29 Apr 2008 10:21:39 -0500, Roger Shoaf
wrote:

Tapping cast iron is not too difficult, especially if you are using sharp
tools. One thing you might want to consider is to do it on the vehicle,
cold with the engine off. You can rig compressed air to flow in to the
tail
pipe and that way the air pressure will blow the swarf out.

You can loosen something along the way to allow a little pressure to
escape.
I think about 10 to 15 PSI should do the trick without blowing anything.



I see what you mean. I found some cast iron elbows and drilled by
hand. It drilled quite easily. Of course I didn't make a straight hole.

--
Wayne D.