Limited disassembly of a 1980 IC 196

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.
 
Robert kenney said:
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.
Click to expand...

Robert,
I'm all ears here. The t04e was off the top of his head. There are critical subtleties to turbo selection I'm not up to speed on, such as a/r ratios and a thing called "trim", but would have asked about before actually putting money down.

The numbers I came up with, using 196 c.I. And based on 80% efficiency and usual assumptions, are about 275 cfm @ 4,000 rpm, and 1.5 pressure ratio. Compared to other engines, which turn much faster, this is rather modest. Anyway, a 152's flow is even smaller. What flows are you looking at? You'll be spinning faster and probably going for more boost? How does the turbo you mentioned for your use, look with my flow calculations?

The above numbers are why I thought a trw b flow was unacceptable, an f flow marginal, and an e flow the way to go. I have those maps, as well as some t04maps. These numbers put me on the 70% island.

I don't want real early boost, but say, up around 2,800 rpm on up. For me it's all about keeping power up as the altitude increases.
 
Maybe you miss read my post.
The t04e in whatever trim, is some what large for your application.

The ve peak is at peak torque and there you May expect it to be 80-85% on a stock IH head. I would use 2600 at 80-85%.
188 cfm = 14.3 lb/min

at the peak hp range (4000) it will be down considerably below 80.
Because it is a guess based on the typical IH torque curve which correlates closely to ve I would use 65-70% ve.
221 cfm = 16.8 lb/hr

I feel that once you factor intake losses you'll be closer to 1.7 pressure ratio to achieve 7 lbs.

I picked the gt2554r or the gt2560. Maps out much better with the expected mass flow rates and pressure ratios.
 
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Robert kenney said:
maybe you miss read my post.
The t04e in whatever trim, is some what large for your application.

The ve peak is at peak torque and there you May expect it to be 80-85% on a stock IH head. I would use 2600 at 80-85%.
188 cfm = 14.3 lb/min

at the peak hp range (4000) it will be down considerably below 80.
Because it is a guess based on the typical IH torque curve which correlates closely to ve I would use 65-70% ve.
221 cfm = 16.8 lb/hr

I feel that once you factor intake losses you'll be closer to 1.7 pressure ratio to achieve 7 lbs.

I picked the gt2554r or the gt2560. Maps out much better with the expected mass flow rates and pressure ratios.
Click to expand...

I would think that your numbers are the reality, and that I was off. Let's go with that. So in going back to the flow charts I looked at, a b flow would have been maybe possible, and the f flow closer to what was needed. So I live and learn, although dodging bullets in the meantime! Edit: if I plug your numbers into the e flow chart, it looks like I run to the wrong side of the surge line, which I read as having a turbo "too large" and this can hammer the bearings. Perhaps this was the cause of the failure.

Couple of thoughts for discussion of what paths forward look like for me. My cast iron elbow has a t4 flange. The ideal would be to retain that, so the deal becomes finding a turbo with that flange, and in the flows thus described. If that isn't feasible, then I'm staring at fabricating a comparable elbow to accept a different flange. I've thought on this previously….the triangular cast iron flange base is 5/8" thick, for strength. Maybe do this in 1/2" steel; a small bevel wouldn't be difficult to machine into one side to serve as a mating surface for the metal donut pressed into the manifold. Then what, schedule 40 pipe that has a comparable curve, and then top it off with a t25 or whatever flange. In all, a weldment. This is where I would have to go.

Then it gets back to blow-through or draw-through. Legitimate reasons for both. This is the framework I have to work with.

Any further thoughts or discussion appreciated.

Edit: the root cause of the bearing failure has been discovered. Clark's corvair turbo guy pointed out my error. Although the turbo oil feed can physically come in through the bottom, you don't do that. Gravity is not the bearing's friend in this orientation. You must bring it in through the top of the bearing housing. No comments, please - I have already been punished enough. :frown5:
 
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No punishment from me :icon_xd:

I'm glad you found the likely root cause.

I do have a t 152 center bearing assembly that I can say for certain I'll never use. I will have a closer look at it this coming weekend if you can use it... I know both wheels are on it.
 
Robert kenney said:
no punishment from me :icon_xd:

I'm glad you found the likely root cause.

I do have a t 152 center bearing assembly that I can say for certain I'll never use. I will have a closer look at it this coming weekend if you can use it... I know both wheels are on it.
Click to expand...

Robert,
I would be so grateful for that. Please let me know!
 
Robert kenney said:
maybe you miss read my post.
The t04e in whatever trim, is some what large for your application.

The ve peak is at peak torque and there you May expect it to be 80-85% on a stock IH head. I would use 2600 at 80-85%.
188 cfm = 14.3 lb/min

at the peak hp range (4000) it will be down considerably below 80.
Because it is a guess based on the typical IH torque curve which correlates closely to ve I would use 65-70% ve.
221 cfm = 16.8 lb/hr

I feel that once you factor intake losses you'll be closer to 1.7 pressure ratio to achieve 7 lbs.

I picked the gt2554r or the gt2560. Maps out much better with the expected mass flow rates and pressure ratios.
Click to expand...

For the sake of documentation, I discovered the trim values for the trw/rayjay turbos. Not that I really understand the relationships of these numbers.
Compressor:
b = 29
f = 37
e = 56

turbine:
b = 45
f = 58
e = 66
 
Mark I found it and it doesn't look to bad. Some bearing play but the turbine looks fine. Comp leading edges leave a bit to be desired.
Pay the ups charges and it's yours.

photo 1.jpg

photo 2.jpg

photo 3.jpg
 
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Robert,
that turbo arrived. Profuse thanks for this item! It had a very hard life, but the most important part appears to be solid, and that's the center section. The piston ring bore looks good and the snap-ring lands haven't been crunched. I've seen this before and don't understand how it happens. Maybe they have turbos rebuilt in the ape house at the zoo and give them hammers.

The inventory of the other parts is: b flow turbine - grooved journals. Bummer, dude. Bearing and the mating ring are toast.
I imagine the step-gap piston ring is still good. I have a bunch of used ones and can't see replacing one unless it overheated and lost its "spring".
B flow impeller - chipped and bent blades, but that was known.
Compressor housing. Better than the one I have on hand, so that's a plus. Edit: oops, stripped threads.
The carbon face seal and its mounting "dish", shims and spacer were missing. I have two good spare carbon face seals and a selection of shims, spacers, and snap rings.

So I have basically all the parts on hand to put together an original b flow IH turbocharger. I'll order a new mating ring; I have all the gaskets on hand. I'll order a new viton o-ring for the "dish". These turbos are surprisingly simple.

I'm going to be in socal on business all next week, so hopefully I can begin putting the "puffer" together right after that. So look for that step-by-step pictorial of its resurrection. Later on I'll adapt an f flow corvair compressor housing for better flow but for now the b flow should work well enough.
 
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