Limited disassembly of a 1980 IC 196

So close to getting it off the stands but getting the carb to run half-way right is now the obstacle. Solutions May realistically take several weeks - or more - since I think I'll need some special bits, plus my day job has thrown me some curves and I'll be traveling more…

the mechanical stuff is easy, the tuning stuff is the pain if you are plowing new ground, which I most certainly am. I'm sure Robert will confirm that fact. Here's what's going on:

1) the carter yh side draft is a good, but not ideal, choice for what I'm doing. But webers are $$$$$, so it's the carter. I have some slop in the linkage which keeps the throttle from closing tightly. That will require a spot weld on the lever-thingie attached to the throttle shaft, re-sizing the hole on my bracket to the little cross-shaft doesn't move around (will post a pic to illustrate, but much of the problem is in this area), and adding an additional return spring and lever to that side of the carb. Again, a pic will illustrate the issues.

2) icing. Heavy frost built up on the exterior of the adaptor between the carb and the turbo compressor housing. The housing itself quickly warms - a relative term - from the a/f mixture it is mixing, even at idle. Yesterday I added the hot air tube from the snorkel back to the cast iron elbow and ran it. The adaptor now seems to only be cold and the frost has been greatly reduced. This shows that sufficient hot (100 degree plus) air is going into the carb. Much as I hate to think about it, I am thinking of pulling the adaptor and adding a block to its underside, by this I mean casting a block of zinc (900 degree melt temp, which is less than aluminum) to the existing aluminum casting, which shouldn't hurt the adaptor, and then drill it for a hot coolant passage. This should cure the adaptor's need for heat.

3) but the real problem is that the carb seems to be loading up and won't rev clean or crisp after warming and the choke comes off. Couple of thoughts on this: to make sure I'm Rich enough under boost while tuning, I put in the richest rod available. This rod/jet combo is custom made for these, since oem rods and jets are no longer available. The jet is a new edelbrock jet and the rods are machined to match oem flow specs, come in stock flow, and 3 richer steps (and three leaner steps) for tuning. I May be running "pig Rich", in fact hope that's the case as the fix is easier. I have the oem stock rod and jet and these were suitable for a 164 c.I. Engine but I'm 32 c.I. Bigger than that. But as this engine turns sloooow by comparison, that May at least put me back in the ballpark for crispness and decent throttle response while running n/a. If this is the problem, then I can tune from there.
I have an 02 sensor in place and found an old k&n a/f meter I forgot I had. I can hook it up to see what my a/f is (has those little lights). At least it will show if I'm running laughably Rich! :yikes:

4) the yh had a problem with the float controlling fuel shut-off when the original 0.081" inlet float valves went away and were replaced by aftermarket 0.101" valves, or so it is reported. Flooding was common. I went to a custom ball-bearing valve style which helps some, but I am staring at probably running a return line and a regulator to get fuel pump pressure below 5 psi (my Scout pump puts out a healthy 5 psi). These are not insurmountable problems, but do have known solutions. This basic setup on my corsa worked perfectly so I know this can be fixed. It's just frustrating to have to do this so close to getting it on the road.

Edit 1: warmed it up. The k&n a/f meter indicates around 15.1 at idle, and vacuum is steady at 16.5 inches, which is good. Blipping the throttle isn't crisp but seems to be like if you have too much accel pump squirt (know what I mean? What they call "blubbering"?). But this doesn't seem to be reflected in the a/f meter, which runs no richer than the ideal 14.7 "light", maybe one light richer. Fast idle (2,500 rpm) it runs at those same lights, I.e., around 14:1 it May also be partly due to the fact that the intake tract is much longer, I.e., throttle blade much further away from the valve train. The adaptor runs tepid/cool, and the compressor housing is very warm, so whatever fuel that enters the turbo ends up being quite mixed and hot in the manifold, which is one benefit of a turbo. I don't seem to have any vacuum leaks (sprayed starting fluid around all joints and idle did not change). I think I've solved the problem of the leaking oil feed line.

Edit 2: pulled the carb. I definitely need to tighten up the linkage so the carb will return to idle. The little bracket swedged to the end of the throttle shaft is really loose and is half the problem, the other is linkage further down the line. A couple of tack welds will set some things right in this area. Looks like the fitting in the base of the adaptor (nipple for the pcv hose) wasn't screwed in tight. May have been a vacuum leak here. Took carb apart. The special ball-bearing float valve had rough threads and I didn't get it screwed into the carb top cover as far as it could go, so I think that fuel May have been coming into the float bowl around the threads. I have other evidence that the float level May have been way too high, as well. So now I am resetting everything and tomorrow should have it put back together and then we'll see what was what.
Scout is off the stands! Just need to get decent throttle action and a repeatable return to idle before I take it for a drive.
 
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The engine compartment is now very busy in this area. I have rerouted the heater hoses (first pic).

2nd pic. Below the carb is a cross shaft that has a lever on the opposite end that connects to the throttle cable. On this "linkage" side the hole is sloppy and the return spring on the throttle cable cannot provide enough force to "bring it all home" and establish a solid idle return. So I have fashioned another lever for this side so that an additional return spring (plus fixing the sloppy hole) will make things operate properly. Note the hot air tube going to the snorkel. IMG_1144.jpg

IMG_1145.jpg
 
It seems like that carter carb is going to give you fits off road. Have you given any though to using a stromberg?
 
Maybe, maybe not. I don't plan hard-core off-roading, but we'll see. The yh has some known problems, but are fixable. So far the troubles are self-inflicted. Today I need to fix very practical things, like hooking up the e-brake cable. After fixing the linkage, the first thing to do is drive it and see where the a/f mixtures sort out. What I have now for measuring is crude, but I still need to get an innovate lc-2 02 sensor in there for data logging.

The other thing that is apparent is that there are few choices for side-draft carbs for my application. The carter was used successfully in slaloms, etc. With a vent modification, not unlike what's posted on the other board about the 2-bbl carbs. Keep in mind that the yh is a side draft version of a yf, which is down-draft, and was used on a gazillion other vehicles, notably the early jeeps with four-bangers. The float bowl is actually the same in terms of orientation, so the basic design is proven and worked with the Jeep in terms of off-roading… :sosp: underhood clearance is limited and a down draft isn't in the cards, at least as far as I can see. IH only got away with the 152t and the 1-bbl Holley only because under hood clearance in an early was significantly greater. The real solution, though, is efi. Period. (don't let bill usn-1 see I posted this! :icon_mrgreen:). But that's for down the road….

Edit: I have fixed the slop in the linkage, and successfully peened the lever at the end of the throttle shaft (it won't accept a spot weld). Made an additional lever that will serve when I hook up cruise control! So when I assemble everything, I expect the linkage will have no slop but still be free (no binding). We'll see how the week goes.
 
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Earlier, I was letting it run and it just seemed to run so crappy, like in loading up, really crappy response to blipping the throttle or running it at fast idle. I pulled the carb's top cover and turned it over to check float action. The "new, improved" (and made in china) ball-bearing float valve was sticking! It was flooding. So I pulled out an old regular type needle valve (another reason to never throw away serviceable old parts from a carb) and put it in and reset the float level, and put in the original rod and jet, just to try to get to a better baseline. It ran much better. And then I couldn't help myself and dared to go for a test run. When it got all warmed up - so the adaptor isn't cold - the engine completely changes character. It runs real smooth and throttle response is very good! So it's a heat issue; very cold blooded. I know I need to work on heating up that adaptor at least until under hood conditions allow coolant to it to be shut off. I have a plan on how to do this.

Anyway, the engine is quieter than with the stock stuff on it, mostly due to the exhaust system having more mass to it, better sealing with the 3-bolt flange, and the quieting effects of the turbo itself, which is a known effect.

I put five gallons of premium in it.

Initial impressions on the first real test run. For those of you familiar with my geographic location, foresthill road is a favorite of the motorcycle set. At driver's flat, a long, sweeping curve maybe 1 mile long, the elevation goes from something like 1,200 feet up to 1,600 or so. Guess on my part but easily confirmed with gps, which I'll do later. Anyway, the point is that even with a head start of about 40 mph on the curve, I can only top it with great effort in 3rd at around 45 mph or so. Today I started from a dead stop and really don't know how fast I ultimately can take it because the Scout is a handful as I easily topped it around 60 mph in 4th. So I certainly was in boost to pick up another 15 mph. Further up the road, to around 2,600 feet, I struggle to keep 45 mph. 55 in third was a breeze, and there was more pedal left.

I was running the original jet and rod. Though I didn't hear the deadly "detonation", I don't know what my a/f ratio was under those conditions, nor the boost level. Unfortunately, my laptop with the megajolt program in it, took a dump and needs to be reloaded. So data logging must wait until the laptop is fixed. I really wanted to know what boost levels I did reach. I didn't feel any sensation of being pressed back in my seat, but the engine simply kept pulling on the little grades like it wouldn't before. I am certain I'll need to increase my mixture strength, and I have a couple of rod selections that should help me get there. Oh, and the turbine housing really gets hot. After these little "pulls", things smell like they're getting too toasty!

a lot more fun. Almost like a v8.
 
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Second test run. I think something has happened, but not sure what. I May have blown a head gasket, or possibly the carbon seal on the turbo has begun leaking, not sure which. I have lots of light colored smoke coming out of the tail pipe. Don't know if it is coolant (steam). :yikes:

how do I diagnose what's going on?
 
Doubt it is a head gasket but an easy test is to use your nose.

Pretty obvious if it is coolant vs oil.
If you are passing oil through the seal you should see evidence of it on the plugs and in the intake.
 
It's really strange. What would my nose tell me? What would a head gasket leak smell like? Let me just run by you what I know.

I had gone for a run and was parking it. Suddenly lots of white smoke (or real light colored smoke) at idle; revving it up, lots of smoke. No unusual noises, temp gauge normal, plenty of coolant. Nothing unusual in the oil that I could see, no bubbling in the radiator neck. Then I shut it off for a while and did other things.

Came back and started it up. Some of the smoke appeared, then mostly went away. The smoke coming out the tail pipe is dry. Almost seems like the vapor you see with a fresh start, but doesn't go away. Here's what puzzles me. This engine seems to burn real clean, even without a cat. I am not sure there's a connection between this condition and when the engine is completely warmed up and the adaptor is warm. I think the excess stuff appears when its really cold/some frost. Could I be running a little Rich and cold and it's "slugging" in the turbo? I put in the aftermarket jet/rod combo with a metering rod +1 Rich over stock, and fired it up. Condition about the same. So I've shut it down for the day, I'll worry about it tomorrow, maybe.

One thing I'll say is that whatever, once warm, this engine runs real nice, much more "street able" than the Holley 1940.

Any further thoughts appreciated. Maybe tomorrow I can pull a couple plugs, maybe run a compression test. What a super pain that will be, with the turbo plumbing in the way. Pulling the intake elbow won't be pleasant, either!
 
Ummmm, oil will smell like oil burning and coolant will (assume antifreeze not just water) like coolant and the exhaust will condense out moisture quickly on a cool surface even at normal running temperatures.
 
Uh, what can I say? :icon_rotate: smells like hot, dry exhaust that hadn't been run through a cat. I did the paper towel thing against the tailpipe and it stays clean and quite dry. I don't smell anything unusual.

Tomorrow I'll dig further into it.

Edit: I just remembered that a few minutes before this, I was up the street visiting a neighbor and shut it off. It did one of those "run on/backfire" things, quite substantial, actually. Maybe it unseated or damaged one of the seals. Would oil burn or smoke, a very light color?
 
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Mark pietz said:
Edit: I just remembered that a few minutes before this, I was up the street visiting a neighbor and shut it off. It did one of those "run on/backfire" things, quite substantial, actually. Maybe it unseated or damaged one of the seals. Would oil burn or smoke, a very light color?
Click to expand...

That is a critical piece of information. Yes, absolutely on a draw through application like you have, an induction back up will ignite an large volume of fuel and air and very likely damage something in the process.
 
I just started it up and let it ran. After the engine warmed up - and there's lots of moisture in that long 2 1/2" pipe - it clears up. Then I stand there and run it at a fast idle, standing outside with one foot on the gas and an eye on the tail pipe, and then after a while light smoke begins to come out of it. I stink from exhaust. I think it May be oil, not certain. I did check the #1 spark plug. It wasn't oily, but was darker than normal as in Rich. Not sooty, but chocolate. Seemed to be a tiny orangish fluff deposit on the ground electrode. I know one thing, for certain. The IH mechanics must have hated working on the 152t. For me to do a compression test, I'll simply remove the turbo system from the cast iron elbow out. I imagine the mechanics would draw straws on who had to work on one. The guys pulling the long straws got to commit suicide - they were the lucky ones - the short straw guy got the job.

I'm thinking of pulling the turbo and disassembling it to check for leakage. If it's leaking through the carbon seal, or maybe the "piston ring" on the hot side, it's slight, but enough to cause smoke.
 
The mystery is solved. The turbo seized. The results of the post-mortem are not completed. It was getting oil, the bearing was new, and all the specs were met.

The bearing completely wallowed out, probably 1/8" or so on both journals, when the e wheel stuck.

I'm going to pour myself a big glass of whine. :cry in: and think about it all tomorrow.
 
I would be interested to know how oil is presented to the turbo bearings. Eg direct pressure or indirect via a wick or similar. If you had oil it should have survived a few runs.

I wondered if the small turbo would be pushed in to a critical rpm range with the larger engine.

Tough to re-plumb but I would consider a modern unit if you are considering reusing the older unit

either way sorry to hear about the complications.
 
Under pressure. Needs at least 10 psi at idle, so I had that in spades, as they say. The bearing is oiled through a hole in the casting, which enters a circular groove around the center of the bearing. The bearing itself has holes around the central portion and oil enters through the holes. So it was getting oil.

I wondered about the critical speed. Possibly, but I don't know. The rayjay is essentially a rebadged trw if a b or f flow, and rayjay made an e flow, which is the same turbo with a larger wheel and larger turbine than the f flow. It was made to handle engines between 200 and 300 c.I. Identical in all other respects, though. My calculations showed good flow (70% island) at 4,000 rpm, so I don't believe it was overstressed. In fact, my calcs. Showed the 196 to flow at 4,000 rpm what the corvair f flow had at 5,500 with a 164. So I think overspeeding wasn't the problem. In fact, I know on the grade where I can muster only 45 or so in 3rd, I'm spinning only around 3,500, if that. Wringing it out further only makes a lot more noise without the benefit of performance. I can't imagine I got near 4,000 rpm.

But this is academic in that I don't know what happened. What's done is done and you could be right. I have a thought, though. When I first fired it up, it had oil pressure almost immediately and I did confirm flow out the drain hose, so it's had oil all the time. But in fear of running lean, I put in a very, very Rich jet/rod combo. In fact, the engine blubbered from it. I idled it until it got warm and d*cked around with adjusting the idle, etc. But the adaptor was running heavy frost a lot of the time. As we know that's consistent with boyle's law (refrigeration) and I wonder if all that raw gas flowing through the compressor washed behind the carbon seal and thinned the oil in the bearing. There was a very black carbonie stuff (best word, but not thick) coating the turbine shaft. But it wasn't burnt. I tired of the blubbering, figuring it wasn't drivable that way, and installed the original jet/rod and it ran very well, so that's what I ran the couple of times it was on the road. Probably not more than 50 miles total on it. My real concern is where all that bearing went. I've been checking the oil the past few days and didn't detect anything amiss in the oil, but now I need to get a smear on a tissue and get it in bright sunlight.

Guess this rules out a blown head gasket, huh?

I have a headache now. I'll think about this tomorrow. But I am at a crossroads. I know This modification can work, but where do I go from here.
 
My brain churned all night over this and I believe it finally spit out a potential cause for the failure.

I'm remembering that I had difficulty in sealing the 1/4" brake line that feeds oil comes from a 90 degree ell on the block by the oil filter. I had to make that flare four times before it wouldn't leak. So I made my first run and confirmed I was getting decent boost under some conditions. It began weeping again. So I really tightened it down. I am thinking that I crushed the flare and restricted the oil flow. That portion of the oil feed line is still intact as it was when it last ran. It will be a few days before I have the time to crank the engine over and see how much oil comes out of it. If it's pretty low, then I'm betting on that as the cause. Actually, I'm hoping it is, even though it means I was careless and screwed it up.

In any case, I have a lot of other very real distractions in my life right now and don't have the time or money to replace this turbo or go down the path of using a newer style. I was sooo close but have hit a wall. :mad2: I need the Scout to be a driver right now more than anything else. So my plan is to carefully remove all these pieces and box them up, for some future day, and put the original parts back. I'm hoping that a few oil changes will clear out the aluminum fines that resulted from the bearing failure. Hope I haven't done any real damage to the engine, but time will tell.

I'll report back after I test the oil line for flow.
 
Don't give up as you're almost there! When you go to redo that oil feed line bring it here. I have a real nice flaring tool that only takes a few seconds to make a super nice single or double flare.
 
The flare I made was, in fact, not a restriction. The line was clear. So I am very confused. I cranked it over a fair amount and didn't see oil coming out after maybe ten or twelve revolutions. The engine always generates oil pressure quickly and always has - probably within 3 seconds after firing the rattle goes away. Cranking like this always gets the needle to move up. I would imagine even at cranking speed, the oil pump would be quickly pushing oil up a small tube about two and a half feet long.

The immediate cause of the failure was oil starvation, but I now really don't know what the "root cause" was. In addition to the wiped out turbine and questionable impeller, the piston ring ruined the bore it rides in in the bearing housing. So that's toast, unless I can get clark's corvair to machine it out and bush it. This is now getting a bit pricey and I don't know exactly how much I want to do with this, especially since the real cause is unknown at this point.

I'm even open to another turbo, if I can find one with the same footprint (t4 flange) that has or can have an oil seal on the cold side.
 
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For lubrication oil I won't use anything smaller than -6 line. -6 is the id on flex. Hard line or tube is rated by the od so 1/4 tube is small on the id. Less than 3/16 if I'm not mistaken but dependent on wall thickness.
 
I've been following your project Mark and I feel your pain. I wish I had some experienced advice to offer, but I don't. I am however, very glad that your radiator is controlling engine temps in general. Good luck, and as I keep telling myself at these junctures, "that's why they call it hot rodding!".
 
The factory used 1/4" line, so I followed suit, without thinking. Perhaps it was marginal at best. It's academic now, and maybe that was the cause, maybe not. I won't know, either, but the question is where do I go from here.

The f turbine is toast and the e wheel had some scratches but no dings or pieces missing. Would I trust it? I really don't think so. The piston ring seal on the turbine ate the bore it sets in in the bearing housing. That's the deal killer. That particular bearing housing is unobtanium, although it could be repaired. The question becomes one of economics, as I am now pushing better than 50% of the cost of a new turbo.

For a number of years I've been following one of the corvair guys who has done a lot of development in converting carb systems to blow-through (his projects can be seen on the web if you google "dave binnie". First class work. He must be an engineer). Had occasion to speak with him yesterday about the trw unit. He finally abandoned the trw and went with a new garrett t04e. The sizing looks right. Of course, he knows my project isn't a 164 c.I. Corvair but a 200 c.I. IH. The t04 has the same t4 flange and overall geometry so it should just bolt up like what I have, and welding on an exhaust flange to the existing outlet pipe shouldn't be a biggie. The question then is blow-through or draw-through.

At this point, I don't have a grand to throw at the project and the mental energy and time to commit to working out the details, although I am going to follow through and get the specific part numbers for rising rate regulators and stuff like that in case I do. If I go blow-through, I'd have to figure out a hat for the 1-bbl Holley or make a box and add a blow off valve. A waste gate is problematic. If I stay draw-through, then a new adaptor comes into play, and ensuring the t04e has a seal on the compressor side. So any Path forward is completely new ground for me, a new learning curve.

Robert is going blow-through so I'll anxiously follow his progress to see how he gets that done. It should give me insight for when I get this thing back on track. I appreciate all his help to this point.

For now, I need to fall back and regroup. :shocked:
 
Engine displacement is practically irrelevant to the choice of a turbo. You need to calculate (using the educated guess technique) peak gas flow for the turbine and the air flow for the compressor then apply those flow numbers and pressure ratios you expect to the turbo maps. Fairly quick and easy math.

The t04 is way to big if you want boost early and these are tractors so early boost onset is beneficial.
 
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