300* drop is a good rule of thumb to be sure, but as I'm sure you know, every model of turbo/turbo setup is different, and I'd like to be a little more precise if possible...

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1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

Quite a bit more than $20 in the Seattle area, I can assure you. Plus you're forgetting the cost of the gaskets & other little anciliary items...

I'd think actually just removing the turbo would do, if you have a close-quarters right angle drill and a short bit. I don't see where removing the entire manifold would even be required.

On another note, if you use a donut-shaped magnet and put it against the manifold around your drill bit when you're drilling and around your thread tap when you're cutting the threads you'll catch 99% of the shavings, so I don't see where you'd really even HAVE to take the turbo off.

The few tiny filings that might escape to the inside of the manifold would only be from that last fraction of an inch when you actually break through with the drill. I'd think that many little filings would be able pass safely through the turbo impeller and out the exhaust in about the first 30 seconds of idling the very first time you start the engine when the impeller wheel is barely even turning. Can't see where that would cause any damage worth being concerned about. Heck the impeller chews up flakes of carbon that get blown out the exhaust at WOT - when its spinning at tens of thousands of RPMS - without being damaged...

Is there a flaw in my logic here somewhere?

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1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

Only way to do that is to know the temperature drop for your climate, engine and driving style and that means a probe pre and post turbo. If you're going to do that, might as well just go with a pre turbo probe and be done with it.

Post turbo probes are mainly for maximizing economy, "driving by temperature", as I said earlier.

Removing the turbo and manifolds is very easy and a gasket set costs $35. If you can weld a bung onto an exhaust pipe I know you can use a drill and tap.

That 1% is all it takes to do damage. A wheel spinning at 120,000rpm doesn't take much to get off balance and take out the bearings. Iron is much harder than carbon and soot. A shaving can easily get wedged between the wheel and housing.

Some "lazy" shops drill and tap with the engine running around 2000rpm. The idea being exhaust pressure will blow any shavings out before it can drop in.

Umm, yeah, I'm a pretty experienced fabricator - so doing this job wouldn't be much of a challenge for me.

However, everyone reading this might not be in that same boat so to speak...

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

I agree - if the turbine is spinning at 120k RPMs when the shavings pass through it. If they pass through at idle when its barely turning its a different story. If one got wedged like you describe, it would stop the wheel, right? That should be pretty easy to determine and fix before it does real damage.

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

Harbor Freight sells tap sets, drills and bits. Its not impossible to get a good pyro system finished DIY for under $300. I've done it once and I've got another pyrometer coming for my 300D.

I bought this gauge and probe from these people.

http://www.egauges.com/vdo_mult.asp?Type=Pyrometer&Series=Vision

works great and cheap! and VDO to match the car. I borrowed the tools, but they could be had from harbor freight for around $20

In my opinion doing it anyway other then the manifold on the bench is just asking for problems. and its really not that hard to remove and install. swapping to a pre EGR manifold was a plus.

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I would say the EGT is there to detect poor conditions of combustion resulting from
-Poor atomization (Bad Injector or Delivery Valve)
-Leaking Valve
-Bad Compression
-Overload
-Bad timing
-Poor air supply

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Retired Marine Engineer
2005 E320 CDI
1987 300 Turbo Diesel @ 300,000 kM going
1974 240 D 300,K Miles when given away gone
1970 200 D gone
1969 190 D gone

I have a question. When i drilled my diesel ram. I started the hole then started the engine & finished the job. Shavings blew out from the hole. Shut the engine off, tapped the hole & installed the sender. How is the 300SD different?

It isnt. Doing it that way is a good way to cause damage. Shops with good mechanics won't allow shortcuts like that.

I like the idea - pretty much no way for even one filing to go inside against constant positive pressure...

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

Agreed. There's almost no risk if the engine is running while the hole is drilled.

That is the lazy/improper way to do it. Do it right.

In your opinion. I think it is the easier/simpler and therefore more effcient way to do it.

Feel free to do things the hard way if you like. I have a life so I prefer to do things more simply and efficiently.

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

ok so this is what im thinking... i got a saab 900 intercooler coming to me soon so im going to do the pyrometer and the intercooler and the full load fuel screw all in the same weekend hopfully, i was going to take the turbo off and while im drilling im going to put a big magnet on the other side of where the hole will be and while im drilling the hole i will have my brother hold a shop vac by the drill bit grabbing any metal flake that will be present and then running the vac inside the manifold before i put it back together, what do u guys think?

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1985 mercedes benz 300D turbo diesel
1998 VW GTI VR6
1996 VW GTI 2.0
1999 saab 9-3 turbo
1987 300sdl (sold)