Limited disassembly of a 1980 IC 196
- Thread starter Mark Pietz
- Start date
Mark Pietz
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This stuff.
Edit: silly me. I think I figured out why some posts show the pics and other just show the file names and you need to click to open. If you write the text and then add the pics and the close it out and submit, you get names. If you begin with inserting pics, and then finish the text and submit, you get a pic.
Update: hope to finish the exhaust system by next weekend. The past two days has been an agony of cutting/fitting/repeating getting the tubing around the block and front driveshaft. Discovered that the left-over piece - with mandrel curves - of that early corvair turbo pipe, will be adaptable and "fill the bill" as it tucks between that boss on the bell housing (with the large threaded hole used for other applications, but unused on the Scout) and the shaft. The challenge will be cutting a series of 15 degree wedges and weld them into a curve to go around a corner at the bottom. Pics to follow and explain… I have found the welder settings that work for the 18 gauge tubing, so life is good.
Edit: silly me. I think I figured out why some posts show the pics and other just show the file names and you need to click to open. If you write the text and then add the pics and the close it out and submit, you get names. If you begin with inserting pics, and then finish the text and submit, you get a pic.
Update: hope to finish the exhaust system by next weekend. The past two days has been an agony of cutting/fitting/repeating getting the tubing around the block and front driveshaft. Discovered that the left-over piece - with mandrel curves - of that early corvair turbo pipe, will be adaptable and "fill the bill" as it tucks between that boss on the bell housing (with the large threaded hole used for other applications, but unused on the Scout) and the shaft. The challenge will be cutting a series of 15 degree wedges and weld them into a curve to go around a corner at the bottom. Pics to follow and explain… I have found the welder settings that work for the 18 gauge tubing, so life is good.
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Mark Pietz
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Mark Pietz
Member
"turning the corner", literally. Got this done this evening outside before the light failed….
I tack welded a short stub to the v-band ring, then installed it. Took the old corvair exhaust section and positioned it to get maximum clearance between it and the top of the front driveshaft - about 2 1/2 to 3 "fingers" which is what, 2" or so? That's the best I can do for now, except that I plan on flattening the pipe in this area by either the application of the bfh, or better, since my skills are improving, welding in a flatter section. My suspension would have to bottom before the shaft would actually hit, I think. Anyway, I contoured a welding rod to determine how to section additional wedges to turn the corner at the bottom and head up and to the left to meet the pipe that then runs back to the muffler.
I tack welded a short stub to the v-band ring, then installed it. Took the old corvair exhaust section and positioned it to get maximum clearance between it and the top of the front driveshaft - about 2 1/2 to 3 "fingers" which is what, 2" or so? That's the best I can do for now, except that I plan on flattening the pipe in this area by either the application of the bfh, or better, since my skills are improving, welding in a flatter section. My suspension would have to bottom before the shaft would actually hit, I think. Anyway, I contoured a welding rod to determine how to section additional wedges to turn the corner at the bottom and head up and to the left to meet the pipe that then runs back to the muffler.
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Mark Pietz
Member
I'm really tiring of fabbing this exhaust system, but I am coming in for a landing. Today I finished cutting/fitting/tacking/re-cutting/re-fitting/re-tacking, etc. It's pretty much done except for finishing the welds themselves and cleaning it all up. My welds are crappy, but lots of grinding will smooth things out and make it presentable. The old corvair pipe burned through in places (thin spots where it was stretched when it was bent), but I've been able to patch it.
I have barely adequate clearance to the solenoid and have shielding material to place between it and the pipe. Should work. The lowest spot of the pipe - where it crosses under the bell housing, is just at or slightly above, the lowest level of the crossmember, so if I had a skid plate it would still work. It crosses right under the louvered clutch cover, but since I have v-band clamps, if I needed to inspect or adjust the clutch, it is a simple matter to remove that section of pipe! I still need to make brackets to solidly mount the piping around the engine, like the original, so that everything is mounted solidly at the point the piping goes straight back to the muffler. In my case, it will require reinforcing the strap thing hanging from the bolt that secures the clutch cross-tube bracket (has the pivot ball). This was the oem arrangement.
I have barely adequate clearance to the solenoid and have shielding material to place between it and the pipe. Should work. The lowest spot of the pipe - where it crosses under the bell housing, is just at or slightly above, the lowest level of the crossmember, so if I had a skid plate it would still work. It crosses right under the louvered clutch cover, but since I have v-band clamps, if I needed to inspect or adjust the clutch, it is a simple matter to remove that section of pipe! I still need to make brackets to solidly mount the piping around the engine, like the original, so that everything is mounted solidly at the point the piping goes straight back to the muffler. In my case, it will require reinforcing the strap thing hanging from the bolt that secures the clutch cross-tube bracket (has the pivot ball). This was the oem arrangement.
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Mark Pietz
Member
And these.
Edit: forgot to mention that the 90 degree transition going straight back isn't quite directly under the clutch linkage, but is close. The original pipe is 2 1/4" diameter and dog-legs closer to the transmission so as to not be under it at all. I wasn't about to add a dog-leg - waaay too much work at this point - but chose to simply shift the pipe over a little bit. The issue is that when you disengage the clutch, the rod in the cab goes down, and at the end of this rod is a yoke engaging one of the bars welded to the clutch relay tube. I first wedged the clutch pedal down and then crawled underneath and confirmed clearance, which is about 2" (visible in img 0957). The pipe itself sets about 1" or so above the transmission crossmember, so I think there's sufficient clearance all around. Of course, the first time I'm on a trail and really have the suspension crossed up will be the real test as to how things clear!
Edit: forgot to mention that the 90 degree transition going straight back isn't quite directly under the clutch linkage, but is close. The original pipe is 2 1/4" diameter and dog-legs closer to the transmission so as to not be under it at all. I wasn't about to add a dog-leg - waaay too much work at this point - but chose to simply shift the pipe over a little bit. The issue is that when you disengage the clutch, the rod in the cab goes down, and at the end of this rod is a yoke engaging one of the bars welded to the clutch relay tube. I first wedged the clutch pedal down and then crawled underneath and confirmed clearance, which is about 2" (visible in img 0957). The pipe itself sets about 1" or so above the transmission crossmember, so I think there's sufficient clearance all around. Of course, the first time I'm on a trail and really have the suspension crossed up will be the real test as to how things clear!
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Mark Pietz
Member
And the last. These are looking from front to rear. I think there is plenty of clearance for the front drive shaft even if I don't flatten the pipe in that area. Which I still plan on doing.
Mark Pietz
Member
Oops. Pics didn't load for some reason. Here they are. I still need to weld in the bung for the 02 sensor. Just an added note here. I bought two marman clamps from the specialty exhaust place in rancho cordova. They were pricey. I found the same size (but not the same vendor) clamp in jegs, much cheaper, and with free shipping. This clamp was of slightly heavier construction and more than adequate, but clunkier, for lack of a better word, to clamp up than the pricier ones.
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Mark Pietz
Member
Question for Robert k. I am going to drill a hole and weld in the 02 bung. If you reference the picture looking down on the turbo and first few feet of tubing (shows the old stub and new piece grafted in), where would it be best drilled? In the old section, or further down in the new? Or maybe it won't matter if it's within the first few feet. Thinking of exhaust gas temps here, but if the 02 is heated, it shouldn't matter in any case? My first inclination was in the new portion, where it is vertical and goes down. Sensor would be pointing rearward but clear the cast iron elbow.
Robert Kenney
Super Moderator
I just saw this Mark, sorry.
If you want to measure afr like a wide band sensor, it really should be as close as possible to the collector of the header. I don't know what effect the turbo will have on the readings. So I would say as close as possible to the turbine housing exit.
If you want to measure afr like a wide band sensor, it really should be as close as possible to the collector of the header. I don't know what effect the turbo will have on the readings. So I would say as close as possible to the turbine housing exit.
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Michael Dimock
IH Parts America Sales Assoc.
In the diesel world, egt's are much more accurate when the pyrometer probe is pre turbo. Normally drilled in the exhaust manifold before the collector portion. I know that you aren't using an actual pyro but normally the consensus is 150-200* difference in pre vs post turbo egt's.
Mark Pietz
Member
Unfortunately it won't be possible to mount it pre-turbo, using the oem parts. I have thought of duplicating the cast iron elbow in steel just so I can drill a hole in the schedule 40 pipe it would take to mount a sensor as well as an outlet for a waste gate. T4 flanges are available commercially, and I think a triangular base flange could also be fabbed fairly easily.
The 3-bolt exhaust manifold used for the 152t is a duplicate of the 2-bolt manifold, except for the flange. It also didn't include the boss included on some manifolds for use with a hot air choke (drilled for that hot-air well the tube fits into). If they had, I would have drilled and tapped it for a sensor, but alas, they never did. So I can't!
Although exhaust gasses flowing through the turbine give up heat energy in the process of spinning the turbine, I hope there's sufficient heat to operate an o2 sensor. Iirc, they need to be heated to about 600 degrees. I believe the sensor is heated, which makes this a moot point, or if not, I'd lose function at idle, but it would work when spun up. That's really the condition I'm putting it in there for in the first place - tuning a/f ratio under boost to ensure I don't run lean.
Edit: Mike, I don't know how hot diesel gasses burn pre-or post, compared to gassers. May not even be an issue, but I do not know if that's so.
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Mark Pietz
Member
And this. Now that the tacking for positioning is all done, I removed the entire system and reassembled it in the garage so I can finish welding all the seams. These are all the bends needed to clear the frame, starter, block, bell housing, and crossmember. What is this, 15 feet of tubing and muffler?
It's raining so this is a "rainy day" project.
It's raining so this is a "rainy day" project.
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Mark Pietz
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Got all the welds done on the exhaust piping, even added the bung for the 02 sensor. It's located about a foot or so downstream from the turbo outlet and I'm not worried about it working, as reading about those with the innovate lc-1 (now 2) it works quite well even temporarily placed in the tailpipe, so I don't think this is a thing to stress over.
My 2 1/2" wide fiberglass cloth strip - 25' roll - arrived. It's good to 1,000 degrees f. I will wrap the entire length of the pipe from the turbo to the first marman clamp, which is just past the starter.
Today I had planned to properly mount the wedge and 3-bolt manifold, but the 152t hardware is always at the ready "to surprise". How do I explain this….the mst-113 says to use the usual exhaust locking tab washers, except the pocket machined to accept the bolt head is circular and there are no "flats" that the flat bent over part would go against. Scratch that idea. The mst calls out for five 2" long bolts. When bolted up, these are short inside the little ears on the head, you know, the ones that break off now and then. I need all the clamping I can get so I bought 2 1/2" allen head bolts, cut them down to 2 1/8", plus drilled the heads with a 3/32" bit for safety wire. Easy-peasy, actually. I skimmed the copper rtv on both side of the first exhaust gasket and bolted 'er all up with sae flat washers behind the allen bolt heads. Then on went the safety wire. I bought one of those handy safety-wire pliers (those are so cooool) but even so, I need some work on my technique. Oh, and I used anti-seize as some of the threads do come through the little ears and are exposed. One day those May need to be removed.
Next step was adding the 3-bolt manifold, which is otherwise identical the the common 2-bolt job, except that it points up. Now, the mst calls for two exhaust manifold gaskets. I thought the one going between the wedge and the manifold would go on just like the other, but to my shock, it can only work by mounting upside down! The manifold is upside down and those little mounting buttons are now up where they must contact the cantilever arms cast into the wedge. And at that, the bent over flange part gets in the way of everything. In short, it's impossible unless you severely modify it by cutting off the flange and notching the areas between the ports and right below the holes for the bolts, as any material in these areas hits against the bolts that mount the wedge to the head in the first place!
At this place in history it is impossible to ask anyone from the assembly line how this little trick was done in a way other than what I'm puzzling out right now.
in the meantime, you'd want to figure this all out before you skimmed that rtv all over both sides, right? I managed to use xylol to remove it and after cutting away lots of the metal shim exhaust gasket, I'm probably going to need a transfusion when all the bleeding from my fingers eventually stops. Cutting tin is hazardous!
My 2 1/2" wide fiberglass cloth strip - 25' roll - arrived. It's good to 1,000 degrees f. I will wrap the entire length of the pipe from the turbo to the first marman clamp, which is just past the starter.
Today I had planned to properly mount the wedge and 3-bolt manifold, but the 152t hardware is always at the ready "to surprise". How do I explain this….the mst-113 says to use the usual exhaust locking tab washers, except the pocket machined to accept the bolt head is circular and there are no "flats" that the flat bent over part would go against. Scratch that idea. The mst calls out for five 2" long bolts. When bolted up, these are short inside the little ears on the head, you know, the ones that break off now and then. I need all the clamping I can get so I bought 2 1/2" allen head bolts, cut them down to 2 1/8", plus drilled the heads with a 3/32" bit for safety wire. Easy-peasy, actually. I skimmed the copper rtv on both side of the first exhaust gasket and bolted 'er all up with sae flat washers behind the allen bolt heads. Then on went the safety wire. I bought one of those handy safety-wire pliers (those are so cooool) but even so, I need some work on my technique. Oh, and I used anti-seize as some of the threads do come through the little ears and are exposed. One day those May need to be removed.
Next step was adding the 3-bolt manifold, which is otherwise identical the the common 2-bolt job, except that it points up. Now, the mst calls for two exhaust manifold gaskets. I thought the one going between the wedge and the manifold would go on just like the other, but to my shock, it can only work by mounting upside down! The manifold is upside down and those little mounting buttons are now up where they must contact the cantilever arms cast into the wedge. And at that, the bent over flange part gets in the way of everything. In short, it's impossible unless you severely modify it by cutting off the flange and notching the areas between the ports and right below the holes for the bolts, as any material in these areas hits against the bolts that mount the wedge to the head in the first place!
At this place in history it is impossible to ask anyone from the assembly line how this little trick was done in a way other than what I'm puzzling out right now.
in the meantime, you'd want to figure this all out before you skimmed that rtv all over both sides, right? I managed to use xylol to remove it and after cutting away lots of the metal shim exhaust gasket, I'm probably going to need a transfusion when all the bleeding from my fingers eventually stops. Cutting tin is hazardous!
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Mark Pietz
Member
Wow! Now it is beginning to actually look like a 196t! Seeing today's progress gets me within "drooling distance" of getting this thing done. The main thing now is to cast an adaptor for the side draft carburetor.
Today I bolted up the assembly using the rebuilt turbo and not the "dummy". In doing this over, I would do the following: trim both shim style exhaust manifold gaskets to remove the flange that is present to shield heat from the plug wires. Not needed if one has the original large heat shield, or maybe even if I didn't have it. The gasket closest to the head gets in the way of my plug wires anyway. I still had to cut a chunk out of the flange by #1 plug. I bolted the manifold down to 30 ft. Lbs. And used the oem locking tab washers. I bolted the cast iron elbow to between 30 and 35 ft. Lbs. I customized a g8 bolt (fine) for length and for a castle nut and drilled it for a cotter key. In addition to the other two bolts using flex nuts, I also added the oem lock tabs. I don't want this particular part coming loose.
For now I used flex nuts for mounting the turbo to the elbow, but May swap over to castle nuts and cotter keys or safety wire.
I wrapped the first section of pipe with 1,000 degree f fiberglass cloth tape (2 1/2" wide). I doubled it up in the portion next to the solenoid as clearance there will be tighter than I thought at first.
I fabbed a new 1/4" brake line to feed oil to the turbo. In the original setup, there was tons of vertical clearance and the line came in on the top, but the Scout II hood is much lower. It now feeds in on the bottom. Although I now find I probably could have used the original hole, the new drilled and tapped inlet presents a cleaner look. I couldn't find a tee to mount the feed line from where the sending unit is, so I left that along and got a 90 ell fitting and mounted it in the gallery hole forward of the sending unit (just aft of the oil filter adaptor). Drain line is now cut to proper length so it lays in a continuous downhill slope.
I stuck an old o2 sensor I had on hand, just to fill the hole for now.
Today I bolted up the assembly using the rebuilt turbo and not the "dummy". In doing this over, I would do the following: trim both shim style exhaust manifold gaskets to remove the flange that is present to shield heat from the plug wires. Not needed if one has the original large heat shield, or maybe even if I didn't have it. The gasket closest to the head gets in the way of my plug wires anyway. I still had to cut a chunk out of the flange by #1 plug. I bolted the manifold down to 30 ft. Lbs. And used the oem locking tab washers. I bolted the cast iron elbow to between 30 and 35 ft. Lbs. I customized a g8 bolt (fine) for length and for a castle nut and drilled it for a cotter key. In addition to the other two bolts using flex nuts, I also added the oem lock tabs. I don't want this particular part coming loose.
For now I used flex nuts for mounting the turbo to the elbow, but May swap over to castle nuts and cotter keys or safety wire.
I wrapped the first section of pipe with 1,000 degree f fiberglass cloth tape (2 1/2" wide). I doubled it up in the portion next to the solenoid as clearance there will be tighter than I thought at first.
I fabbed a new 1/4" brake line to feed oil to the turbo. In the original setup, there was tons of vertical clearance and the line came in on the top, but the Scout II hood is much lower. It now feeds in on the bottom. Although I now find I probably could have used the original hole, the new drilled and tapped inlet presents a cleaner look. I couldn't find a tee to mount the feed line from where the sending unit is, so I left that along and got a 90 ell fitting and mounted it in the gallery hole forward of the sending unit (just aft of the oil filter adaptor). Drain line is now cut to proper length so it lays in a continuous downhill slope.
I stuck an old o2 sensor I had on hand, just to fill the hole for now.
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Mark Pietz
Member
And these.
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Mark Pietz
Member
And a shot of how the pipe passes by the solenoid. Once I install the rest of the downstream piping, this pipe will adjust much closer to the starter. I originally had plenty of clearance but when I did my final tack-and-weld, the down pipe moved down and I didn't notice until it was too late and all the other pieces had been "set in cement", so to speak.
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Robert Kenney
Super Moderator
A quick pie cut and weld will fix her up. Even a cut off wheel cut and weld.
Mark Pietz
Member
Perhaps. But then that changes the location of the next pipe in line, and so on. Maybe this weekend I'll have time to bolt it all up and do one last look-see. There May be sufficient clearance and I do have a piece of embossed shield used on a volvo turbo diesel I picked up that will fit around the solenoid. (they call it the "turkey pan" or some such and it goes between the turbo and firewall) and I've used most of it to emulate the original shield that went around the turbine housing. That still to be mounted. I had planned on lining it with some left over fiberglass cloth, but there wasn't any left over…good thing I ordered the 25' roll! If this stuff doesn't work out I'll get the same stuff, but covered in vermiculite, rated to 1,500 degrees f.
Slightly shifting gears here, I obtained a first edition of mcginnis' turbo book off amazon. It was the first version I ever saw and in it they have a picture of the original Scout 80 used by trw to prototype the turbo setup, and a close-up of the engine compartment. What's interesting is that you can tell from the orientation of the turbo's center section (cbra) that it was mounted transversely over the engine. In my picture you see the final production iteration ended up being about 17 degrees off the truck's fore-aft axis.
Slightly shifting gears here, I obtained a first edition of mcginnis' turbo book off amazon. It was the first version I ever saw and in it they have a picture of the original Scout 80 used by trw to prototype the turbo setup, and a close-up of the engine compartment. What's interesting is that you can tell from the orientation of the turbo's center section (cbra) that it was mounted transversely over the engine. In my picture you see the final production iteration ended up being about 17 degrees off the truck's fore-aft axis.