Please comment on my EGT probe placement
Please comment on my EGT probe placement
Took me two brazing attempts, the first one at home and I failed to clean and preheat sufficiently. I got the bung in there well enough, but the manifold cracked and there were inclusions in the joint. So I took it into work, ground out the crap, sandblasted everything, and preheated in an oven to 350. Second attempt came out much cleaner. The brazed-in #8 screw is there to fill the hole I drilled to stop the crack.
So, um, besides "your brazing sucks", what do you guys think?
![[Image: IMG_0927.JPG]](http://lh3.ggpht.com/_o_3o6xcLap8/TPUsJ4bKuaI/AAAAAAAADHA/8RJt7I8CKIQ/s800/IMG_0927.JPG)
![[Image: IMG_0928.JPG]](http://lh3.ggpht.com/_o_3o6xcLap8/TPUsKVGcCtI/AAAAAAAADHE/LkdB5VKwrjs/s800/IMG_0928.JPG)
![[Image: IMG_0926.JPG]](http://lh4.ggpht.com/_o_3o6xcLap8/TPUsJnCY81I/AAAAAAAADG8/7dHl0Wkbf4I/s800/IMG_0926.JPG)
![[Image: IMG_0925.JPG]](http://lh3.ggpht.com/_o_3o6xcLap8/TPUsJOE5quI/AAAAAAAADG4/08HxM9vuNDs/s800/IMG_0925.JPG)
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
This is for the probe that came with my VDO pyrometer. The bung is 1/4-18 NPT, drilled into the manifold and ground to the contour of the inside of the manifold. Filler material is Nickel-Silver brazing rod.
Took me two brazing attempts, the first one at home and I failed to clean and preheat sufficiently. I got the bung in there well enough, but the manifold cracked and there were inclusions in the joint. So I took it into work, ground out the crap, sandblasted everything, and preheated in an oven to 350. Second attempt came out much cleaner. The brazed-in #8 screw is there to fill the hole I drilled to stop the crack.
So, um, besides "your brazing sucks", what do you guys think?
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
--Then again, I know little about cast iron welding....
![[Image: 300TDnoplate.jpg]](http://i190.photobucket.com/albums/z128/alastairhcii/300TDnoplate.jpg)
Alastair E
11-30-2010, 12:09 PM #2Looks good, My only fear would be the unequal expansion between the jointed material and the cast-iron...
--Then again, I know little about cast iron welding....
(11-30-2010, 03:25 PM)ForcedInduction Whats wrong with just a drill and tap?
I was concerned (possibly overly concerned) with cracks growing over time. The manifold's wall thickness is less than 1/8" in most places.. which is actually pretty impressive for 30 yr old mass-production casting techniques. But 1/8" wall and 18 tpi leaves less than 2 threads.
It looked like there were a couple other places with thicker sections, and I was thinking about drilling out one of heat shield mounts. They might have worked too.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
(11-30-2010, 03:25 PM)ForcedInduction Whats wrong with just a drill and tap?
I was concerned (possibly overly concerned) with cracks growing over time. The manifold's wall thickness is less than 1/8" in most places.. which is actually pretty impressive for 30 yr old mass-production casting techniques. But 1/8" wall and 18 tpi leaves less than 2 threads.
It looked like there were a couple other places with thicker sections, and I was thinking about drilling out one of heat shield mounts. They might have worked too.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
Your not going to throw a non EGR manifold on it?
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
11-30-2010, 05:03 PM #5hmmmm .125" wall isn't much... I'd be worried too. Looks good though
Your not going to throw a non EGR manifold on it?
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
(11-30-2010, 05:03 PM)Captain America hmmmm .125" wall isn't much... I'd be worried too. Looks good though
Your not going to throw a non EGR manifold on it?
I was going to, but there's this thing.. you know.. I already have this manifold.. etc. Plus there was more meat right at the joint where the EGR outlet hit the collector, so I figured it'd be easier to put the EGT probe in this manifold.
My guess is that it doesn't matter much for the flow whether that EGR inlet pipe is there or not. I debated making a iron plug and brazing that in, then grinding it flush with the inner contour.. deemed that not worth the effort.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
(11-30-2010, 05:03 PM)Captain America hmmmm .125" wall isn't much... I'd be worried too. Looks good though
Your not going to throw a non EGR manifold on it?
I was going to, but there's this thing.. you know.. I already have this manifold.. etc. Plus there was more meat right at the joint where the EGR outlet hit the collector, so I figured it'd be easier to put the EGT probe in this manifold.
My guess is that it doesn't matter much for the flow whether that EGR inlet pipe is there or not. I debated making a iron plug and brazing that in, then grinding it flush with the inner contour.. deemed that not worth the effort.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
ForcedInduction
11-30-2010, 09:55 PM
#7
Its more than thick enough. The pyrometer is not load bearing.
And my guess is that the sensor weights a few grams and the length of the sensor from manifold to the end would be 5cm. There is not much lateral load along the sensor. 2 threads and some super high heat loctite would do the trick.
Not to bad brazing there i must day.
Mb 1984 w201 om603 swap.
Mb 1986 w201 190E 2.3-16v
Mb 2004 w203 C230k
George3soccer
12-01-2010, 11:53 AM #8Forced is correct. The only load the sensor might endure would be the vibration of engine rpm.
And my guess is that the sensor weights a few grams and the length of the sensor from manifold to the end would be 5cm. There is not much lateral load along the sensor. 2 threads and some super high heat loctite would do the trick.
Not to bad brazing there i must day.
Mb 1984 w201 om603 swap.
Mb 1986 w201 190E 2.3-16v
Mb 2004 w203 C230k
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
12-01-2010, 05:42 PM #9I was thinking that the load would be from the tolerance fit of the pipe threads trying to expand the hole, not the weight of the sensor....
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
1987 300SDL 6spd manual om606.962 swap project
1985 300td euro 5spd wagon running
willbhere4u
12-01-2010, 06:11 PM #10realistically it works either way! I've seen it done before with no I'll side affects!
1987 300SDL 6spd manual om606.962 swap project
1985 300td euro 5spd wagon running
Mb 1984 w201 om603 swap.
Mb 1986 w201 190E 2.3-16v
Mb 2004 w203 C230k
George3soccer
12-01-2010, 08:17 PM #11The heat expansion on that manifold shouldn't be the problem with the sensor in place.Only because it would all come down to the weight of the sensor moving around, when the threads start to expand. Such a tiny thing it should have no problem, with that.
Mb 1984 w201 om603 swap.
Mb 1986 w201 190E 2.3-16v
Mb 2004 w203 C230k
That said.. the worst thing a manifold sees is cyclic thermal induced stresses which eventually cause fatigue cracking.
Forced is right.. the pyro probe isn't going to bust a manifold. But I did manage to make it crack with nothing but poor preheating in my first brazing attempt, and I didn't even get it above a dull red heat.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
Disclaimer: I tend to over-engineer everything. I am an engineer. It's what I do. Tapping would have worked, but I figured I'd get fancy.
That said.. the worst thing a manifold sees is cyclic thermal induced stresses which eventually cause fatigue cracking.
Forced is right.. the pyro probe isn't going to bust a manifold. But I did manage to make it crack with nothing but poor preheating in my first brazing attempt, and I didn't even get it above a dull red heat.
1983 300SD - 350k miles, disassembled for a head R&R
2010 Golf TDI - The wife's car
ForcedInduction
12-03-2010, 07:40 AM
#13
Neither of my manifolds have cracked with a pyrometer installed, even without the support brace installed on one manifold.
The manifold material is not your typical cast iron. It is VERY hard stuff, a real PITA to machine. I installed mine on the under side of the trubo inlet and had ~4.5-6.0 mm of material to drill and tap.
1982 300SD: 304,xxx Super M-pump with 7.5mm elements, 265 Nozzles, GT35 water cooled turbo, M90 Supercharger, A/W Intercooler, Serpentine drive belt, 3" SS exhaust with Magnaflow muffler, 240 breather, AEM dry Filter, Manual Boost Control, EGT / Boost / EMP gauges....Moved on to other projects
1995 F-350 7.3L PSD: 230,xxx 6.0 IC, DIY Stage 1 Injectors, 17* hpop, Tony Wildman Chip, John Wood Trans, 6.4L TC, 3" down pipe, 4" straight exhaust, 310 HP on wheel dyno - 8500# dually: 0-60 in 6.98
Suzuki Samurai: VW 1.9L TD, Trackick doubler transfer case (made by me) 5.8:1 transfer case gears, YJ springs front and rear with rear missing links, wheel base extended 14", diffs welded, some day a VNT.
Rudolf_Diesel
12-03-2010, 08:26 AM #14You should not have an issue with te placement, You should have brazed up the EGR port while you were at it.
The manifold material is not your typical cast iron. It is VERY hard stuff, a real PITA to machine. I installed mine on the under side of the trubo inlet and had ~4.5-6.0 mm of material to drill and tap.
1982 300SD: 304,xxx Super M-pump with 7.5mm elements, 265 Nozzles, GT35 water cooled turbo, M90 Supercharger, A/W Intercooler, Serpentine drive belt, 3" SS exhaust with Magnaflow muffler, 240 breather, AEM dry Filter, Manual Boost Control, EGT / Boost / EMP gauges....Moved on to other projects
1995 F-350 7.3L PSD: 230,xxx 6.0 IC, DIY Stage 1 Injectors, 17* hpop, Tony Wildman Chip, John Wood Trans, 6.4L TC, 3" down pipe, 4" straight exhaust, 310 HP on wheel dyno - 8500# dually: 0-60 in 6.98
Suzuki Samurai: VW 1.9L TD, Trackick doubler transfer case (made by me) 5.8:1 transfer case gears, YJ springs front and rear with rear missing links, wheel base extended 14", diffs welded, some day a VNT.
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