Thinking about a Bus/RV

Discussion in 'Hangar Talk' started by Ted, Jul 17, 2020.

  1. Spring Ford

    Spring Ford Line Up and Wait

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    30,000 miles; 750 hrs at 40mph
    19 weeks at a full time job (40h a week). 9 1/2 weeks a year.

    Holy watersports!
     
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  2. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    In the first year we owned it we spent roughly 11 calendar weeks on the road, with a lot of driving hours and miles. I suspect that your estimated average speed of 40 is probably about right. Average our highway driving (65-75) with the mountain roads and local driving. It’s not fast.

    It’s been great. But I think going forward we’ll see some more weekend trips (like race/motorcycle weekends) and adding longer trips in to hit places we haven’t out west. Plus we have eastern states to make.
     
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  3. Ghery

    Ghery Touchdown! Greaser!

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    Sounds like my great grandfather's approach to building a house. If 1 2x4 would do, use 2. Overbuilt, but they lasted a long time.
     
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  4. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    We just got back from our latest RV trip. This one took us up north to northern Minnesota (Voyageur's National Park) and Wisconsin (the Apostle Islands). We had a good time at both places and would recommend visiting. Best of all, while it was in the mid 90s back home, it was in the mid 70s up there.

    The RV performed great. I didn't get as much of an opportunity to test the solar as I expected as we had mostly nights with electric hookups. However on the few nights where we did run on batteries and solar the next morning, everything did very well. On our last trip we had to run the generator 4 hours or so a day to give the batteries enough charge to maybe make me coffee in the morning. This time we had no problems making my coffee, using the microwave to cook breakfast, etc., and that was even with watching an evening movie, keeping the vent fans on, etc. I'm pretty happy with that performance. My cooling fans for the solar controller are working as intended as well. Basically, everything is looking good there. I do still need to do something with batteries, but I have to decide on what and when. I think the answer is lithium, but not today. I need to do some more research.

    The engine definitely is happier with the new tune. I had 3 good fill-ups with good data, and they were 8.5-9 MPG, with the generator running most of it, towing the Rover, and some stop-and-go thrown in with all of them. That's good consistency and also better than I would've expected previously. I didn't have any legs with strong headwinds or conditions that would've given some particularly bad mileage, but it was surprisingly good and consistent all around.

    I can say I'm happy with my coolant temps and the cooling system now. The pusher fans I added to the intercooler do a good job. Not perfect, of course, but they do make a noticeable improvement in airflow and help with cooling and performance. It's most noticeable if I turn them on and then get on the highway or otherwise have some sort of hard acceleration.

    Before I left on the trip I'd checked the turbo wastegate, which appeared to be frozen - specifically I think the actuator arm is probably seized onto the wastegate arm.. After contemplating its behavior, intake air temperatures, things of that sort, I think what I want to do first is try to free it up, and then see what the new boost, IAT, and EGT behaviors are. From there, I can decide what (if any) changes I want to make to the turbo. I do think there are improvements to be made, but if it's not working correctly now, then it's not a good comparison.

    Back to the drawing board...
     
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  5. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    We got back from 6Y9 yesterday midday, putting 1600 miles on the bus driving up to Michigan and back. I hadn't done anything different on the bus between this trip and the last one, just fluid changes. But this was another test of the solar setup, and we tested it further properly harder than had been tested before.

    Although my batteries are weak and will require replacement, the solar has the benefit of keeping the batteries topped off all the way until the sun goes down, and gets a better charge in since the controller can charge and maintain the batteries at 100% all day. We were able to essentially run house power however we wanted, and power was never a concern. Probably the best test was Saturday morning, where the kids had watched a movie before bed, roof vent fans were on, and then after waking up I made coffee and we microwaved breakfast, running the microwave for about 10 minutes. On our trip at the beginning of the summer this wouldn't have been something we could've dreamt of doing.

    I do still want to upgrade the batteries, but I think given this performance, I'll probably leave what's in there alone for a while longer and continue to evaluate things. The real takeaway is that my solar setup works really well, and as intended.

    The turbo upgrade/replacement would be the next thing on the list. However as I was driving the bus this weekend, I thought how it was really nice to drive the thing, and have all of the systems and improvements I've put in work and make the whole experience nice and what we wanted it to be. It's very satisfying when you get to the phase of a project where you can just enjoy what you've worked on.
     
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  6. charheep

    charheep Cleared for Takeoff PoA Supporter

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    Be careful, talk like this can lead to upgrade-itis...
     
  7. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Fair point, especially with me. The bus still has some open JIRA tickets and things to work on. However, being at a point of being closer to "done" (or at least happily functioning as-is) with the bus and RX-7 means I can finally get back to working in earnest on the Cobra and Land Rover diesel swap, plus finishing up some details on the Morini and BMW that I've been wanting to do.

    I'm glad I've done all the things I did to the bus. However it has come with the price of not finishing other projects that I really would like to be enjoying now.
     
  8. CJones

    CJones Final Approach

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    Time to sell it and start the next one. :D
     
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  9. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Let me finish a few other projects first damn it!
     
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  10. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    I've not done a lot to the bus since the summer, but finally got around to putting the video together about the rooftop solar install:



    Over the winter I'm hoping to address the turbo if I can get enough of a chunk of time to get it apart and work on it some. Silly day jobs getting in the way...
     
  11. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Today's video is overdue, about the oil cooler setup I did:

     
  12. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Random turbo musings...

    The wastegate on my turbo appears stuck as I've mentioned before, and I'm going to do something about it. I think this weekend I may try to pull the turbo and start looking at things, figuring out what I want to do. It doesn't look like it's a particularly difficult removal all things considered. I've had both the exhaust and intake sides off of the turbo at various points and the shaft has seemed to spin freely without binding.

    The stock turbo is sized the way stock turbos are/were normally sized in the 2000ish era on diesels. Something that tends to be biased towards quick spool and responsiveness, decent low end, and probably undersized on the top end. It looks like it's most efficient in the 1500 RPM range on the engine, and I tend to cruise in the 1800-2100 RPM range on the highway. This same turbo is used on 3126s from my rating (330 HP) all the way down to 250 HP. I haven't been able to find a compressor map for this exact turbo, but from what I can gather, I think that at 250 HP it would probably be fine, but at 330 HP it's being pushed a bit more than it should. I've tended to push it a bit on the harder side anyway.

    With the turbo off comes the question of what to do with it. While I've played with turbos in the past, I've never done anything with the turbo on a diesel I've owned, and have been contemplating what I want to do with this one. My goal isn't to make more power, but I would like to see lower induction air temps and EGTs while this thing is working hard (which is most of the time).

    Newer design turbos exist, but it seems that the same turbo design in a newer form tends to end up being slightly oversized. This is an S300G, and going to the newest variant (S300SX-E) and looking at the compressor maps, at high boost conditions the compressor map seems to be fairly close to optimal efficiency (which on that turbo ends up being in the 77-78% range). My concern is that at the low end, this may result in the turbo essentially being too large, unable to work well at those lower airflows. I don't want to put a turbo on that ends up killing responsiveness (especially at higher altitudes) and ultimately increases EGTs since boost lowers EGTs on a diesel.

    I think I could have this turbo rebuilt perhaps with a newer style compressor wheel (maybe newer style turbine wheel too), which would probably improve efficiency and help lower induction air temps.

    The 3126/C7 doesn't have much out there for aftermarket options. One company produces an upgraded exhaust manifold and turbo (PDI). It's pretty expensive at around $4500 for the turbo, manifold, and install kit. I also don't like the fact that they end up providing a non-wastegated turbo. I know this is a common practice on diesels, but I'm not a fan. The 3126 ECU does have an overboost fuel cut-off (something I'm running into now with the stuck wastegate) and for that alone, I think it would be an issue.

    So then comes another more excessive option - which of course then has immediate appeal: compound turbos. This is something that you typically see on various race diesels where you need the combined pressure ratios to get boost levels that are desired. But, especially prior to variable geometry turbos, it's something that exists/existed to help optimize the turbo capabilities for low and high end ranges. On Cummins Rams, it's common to see compound turbo setups where the stock turbo is left in place, and a large turbo is added on the atmospheric side. With the two turbos working together, you end up with a setup that's able to produce higher boost levels at the same airflow/fueling, the end result being lower EGTs, at least so goes the theory. The more I look into it the more I see a lot of people who specifically like this setup for towing, although granted most of them are also doing significant horsepower upgrades (something I'm not doing).

    There's plenty of room in the bus engine compartment with some level of fabrication required, of course. A Detroit Diesel Series 60 K31 turbo is readily available, not all that expensive, wastegated (something else I like) and often used on 5.9/6.7 Cummins as an atmospheric side turbo, and that seems like it could be a good option if I wanted to do the fab work to make that happen. Basically it would involve modifying some intake/exhaust plumbing (not horribly, though) and then making the adapter/mount to attach the K31 turbo to the S300G turbo on the exhaust side. That part would be the most significant work of it.

    I figure once I get this turbo off and can inspect things I may get a better idea of what I want to do and can then decide on a path forward. But I'm thinking the path will probably end up being having this turbo rebuilt/gone through with what upgrades and improvements I can do, and then maybe do something further if I decide more would make sense to do.
     
  13. NealRomeoGolf

    NealRomeoGolf En-Route PoA Supporter

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    You said Cummins so that automatically makes you wrong. :rofl:
     
  14. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    :rofl:

    Hey, similar displacement, similar horsepower, from the turbocharger's perspective an engine is an air pump. :)

    One of the problems with the 3126/C7 from the perspective of someone like me is that pretty much nobody does much for performance upgrades on them. If you go 3406/C15 you can find aftermarket parts and known good build setups all day long. But these little guys don't get the same attention since they never ended up with these engines in a light duty pickup like the Cummins did.
     
  15. SoonerAviator

    SoonerAviator Final Approach

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    Probably a stretch, but I assume that there aren't any easy ways to have a VGT adapted? Compounds aren't too difficult to do, but I'm not sure the juice is worth the squeeze for this application. Surely there's a modern compressor wheel upgrade that may give a tad better flow without compromising the low-end. Or maybe a way to split the housing and adapt a slightly larger snail. Might just email a few turbo companies to see what solutions they have.
     
  16. jsstevens

    jsstevens Final Approach PoA Supporter

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    I just want to point out that this is Ted. Easier is not usually the point...:)

    And I say that with great respect.
     
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  17. SoonerAviator

    SoonerAviator Final Approach

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    Lol, well as an owner of a VGT-equipped diesel, I know there are a few sensors involved in order to control the variable vanes in the turbo so that they react under proper engine speed/load. Not sure if there's a workable solution for that on his Cat without having to have a standalone controller. VGT is more of an "active" solution, where the compound turbos can run "passive" with individual wastegates.
     
  18. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    I would argue that a single VGT turbo adds an extra level of complexity, just a different one in the sense of control mechanisms. In an OEM setting where you've already got an ECU that can easily output a PWM to a solenoid and doing R&D for a million road vehicles, it's one thing. OEMs have moved more towards single VGT turbos and I think in that case it makes sense.

    One thing with single VGT turbos though is that you still run into the pressure ratio limitations and the resultant efficiency limitations. As you get to higher pressure ratios that diesels have been running for the past 20-25 years, all turbos are going to get less efficient, and especially so when you start getting to altitudes out west where that pressure ratio increases since you're starting out with less atmospheric pressure. I'm not running super high pressures in the aftermarket realm, but this engine runs pretty hard, especially driving at 70+ and I do want to get some more efficiency in a manner that lowers EGTs and induction air temps.

    I still think that I probably won't do compounds. But what I might do is replace/upgrade this turbo first, see how it does, and then decide if I want to do something else from there.
     
  19. SoonerAviator

    SoonerAviator Final Approach

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    Agreed. That's why I said a standalone controller would probably needed to get the rpm or engine load signal from the Cat ECU along with boost pressure and then convert it into a signal for the VGT solenoid. It seems like a lot of work and additional points of failure to gain a bit of top-end performance. I figure the easiest (and cheapest) option would be pulling your existing turbo out, then refurbing it with a modern compressor wheel that may give you a bit more flow on the top end. The turbo companies could likely get you a decent compressor wheel to swap in that won't lose much (if any) of the low-end while extracting as much out of the factory housing size as possible.
     
  20. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    That's more or less where I am, at least for the initial step.
     
  21. Albany Tom

    Albany Tom Pattern Altitude

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    I don't anything about diesel engines, but I was expecting this to go down the road of multi-stage supercharger with variable speed electric drive.
     
  22. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    While interesting, that one doesn't make as much sense to do, especially in this application where efficiency is much more part of the goal than outright power (I'm not going for a horsepower improvement). I've only seen a couple of purpose-built supercharged diesels (old Detroit 2-strokes don't count - the blower in them is really not supercharging anything, it's just the force that makes air flow in the correct direction being a 2-stroke). Generally it's a situation where you're looking for response above outright power and efficiency doesn't much matter.

    I am a fan of superchargers on gas engines, though. The E55 Kompressor we had was one of my favorite engines. That was just a really nice engine all around, and the twin-screw blower was great. The XKR's supercharged 4.0L with the smaller roots blower I didn't like quite as much.
     
  23. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    I've been doing some searching and it seems as though I finally found a compressor map for the existing turbo on my bus (S300G), and from that was able to do a comparison between that and the updated version (S300SX-E). It does look like the turbos are essentially the same size compressor wise, but the new one is a solid 4-5% more efficient at all points thanks to a much better designed compressor.

    One thing I'm not entirely sure on is what size A/R the turbine is. I believe it's an 0.8. Looking at various turbine housing size options, 0.83 is the largest wastegated housing that they seem to make. Given that turbine housings can be swapped out to change more or less on its own, my thought is to start with the larger 0.83 wastegated housing and if I find it to be "too large" I could get an 0.8 housing and swap that out. But, I think this is probably the better plan.
     
  24. Albany Tom

    Albany Tom Pattern Altitude

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    Yep, I have very little knowledge of diesels, so had no idea on efficiency. In terms of lag, though, I figured the supercharger would win. In terms of your projects? I see a trend toward the unusual being preferred over the routine, but that's not a bad thing.
     
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  25. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Yes, the supercharger would absolutely win on lag. But when you figure peak boost on this engine is 25-30 psi, then you're taking a lot of horsepower to make that boost all the time and suffer the resultant hit in efficiency.

    It would be an interesting back to back comparison, though. Centrifugal blowers tend to have rising boost curves, so if you set it up for 30 psi at redline RPM, what that would mean for lower RPM (and what you could then also do with some equal length headers, etc.) could work decently well. But in the end, I don't see it being as efficient as turbos.
     
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  26. charheep

    charheep Cleared for Takeoff PoA Supporter

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    Just swap out the engine with the turbo. Seems like less mental work and a lot more fun shopping...
     
  27. NealRomeoGolf

    NealRomeoGolf En-Route PoA Supporter

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    [​IMG]

    ....unless you're suggesting another Cat engine.
     
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  28. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Swapping an engine out wouldn't necessarily be too awful

    I did some base math and measurements on that at some point and I figured that a C9 could fit, but that's about the only bigger Cat engine I could run. When they built the bus (and specifically the bedroom) around the engine, they really didn't leave much room to increase the physical size of the engine. A C9 and a 3126/C7 look to have very similar dimensions, but by the time you get to the C10 and higher, the dimensions grow. So do the weights - similarly a C9's weight isn't all that much more, but C10 and greater gets much higher.

    Another interesting thing is that most C9s out of the box actually are rated at less power and lower RPM than what I have in there. That would be an issue, given that this bus has 4.56 gears and uses the revs of the 3126 on the highway. Some of the marine C9s have power ratings in the 400+ HP range and revs up to 2500, which would work, but then you're also putting a lot more torque through the Allison 3000 (engines at that power rating tend to have a 4000 series transmission). Also I don't know if the wiring harness and interface with the instrument cluster (which is all done over the J1708 computer connection) would be different...

    Honestly, the 330 HP that this bus has is overall fine and I don't really find myself wanting for more power. If nothing else when you're driving your house around, you don't want anything to be too abrupt. You're more limited by cooling than horsepower for long hill climbs.

    Bottom line, I like my 3126 as-is, and I really just want to improve it to be the best it can be. In most cases, that comes down to fixing deficiencies in how the RV and chassis manufacturers (Monaco/Freightliner) decided to interface to the engine.
     
  29. charheep

    charheep Cleared for Takeoff PoA Supporter

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    Gotcha, that makes more sense to me now. More HP, needs a better trans. Which needs a better rear end. Which needs better suspension..

    On a side note, the Facebooks showed me a new subject/show. A guy in Florida goes around and starts old parked diesels. Some have been sitting for decades. Usually he throws in a new battery and they start right up. Pretty neat engineering.
    https://www.youtube.com/@Bruce_Wilson
     
  30. MauleSkinner

    MauleSkinner Touchdown! Greaser!

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    What about swapping engines with your Cat? A pony engine starter on the bus would be cool!
     
  31. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Exactly right on the transmission. I forget the exact horsepower/torque rating on the Allison 3000 series transmission in that application, but I do remember reading it was pretty much maxed out at that level.

    The torque is the big thing, as a big low revving diesel that never feels like it's working that hard (in part because it's never spinning that fast) does have a nicer feel when going down the road in a big rig. But if I compare it to my Ram, it revs about the same at the same speeds, just making more boost.

    If you count the generator, it sorta has a pony motor. :)

    I figure this weekend I'm going to plan/attempt to pull the turbo and attack some other things on it. And then if all goes well, on Monday maybe I can order the new one. That's assuming the Kroil I ordered arrives tomorrow as promised and the bolts actually seem to move and not snap. Other items on the agenda (which ones I do vs. don't do are TBD) are reseal the valve cover (it's been leaking ever since I adjusted the valves), adding a fuel cooler to the fuel return line, adding a water pressure accumulator tank so the pump doesn't run so much, and some other odds and ends.

    One other thing I'm going to do before the next trip is swap in 180 degree thermostats from the stock 190s. Cat recommends against this (sorry @NealRomeoGolf ) but they also are assuming you aren't running electric fans in a rear radiator diesel pusher. The stock 190 degree stats start opening at 190, finish opening at 210. The 180s start opening at 180 and finish opening at 200. Basically, I know I will always need the stats open some, and my goal is to be getting more water flow (and thus more heat transfer) at a lower coolant temperature.
     
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  32. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    Thanks to the good engineers at Cat, this was probably the easiest turbo and exhaust manifold I've removed. No broken bolts and everything came apart easily.

    upload_2023-1-8_13-33-16.png

    The wastegate is very seized, but the manifold is in good shape. Need to do some more research on a few things, but I measured and confirmed that it is equipped with a T3 divided flange and looks to be an 0.80 A/R housing.

    I think from this I know what I want to get to replace it which will be a bit bigger, and debating how big I want to step up the turbine - from 74mm (current) to 76mm or 80mm (my options). I'll still end up sticking with an 0.80 A/R.

    More thinking...
     
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  33. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    I ordered my new turbo for the bus, but more on that in a minute.

    As far as a turbo and exhaust manifold removal go, this was pretty easy. Certainly soaking the bolts in penetrating oil couldn't have hurt anything, but honestly everything came out pretty easily just in general. One exhaust manifold bolt was loose as-is - not falling out but had 0 torque on it. It was pretty obvious none of this had been touched since new, about 23 years and 116k miles ago. Not too bad when you consider that. I see nothing wrong with the exhaust manifold and that's reusable.

    The turbo itself wasn't great. I've seen worse and it was still working, but as suspected, the wastegate was 100% seized shut, and I'm betting always was since we got it - just that before the efficiency upgrades I did to the air system there were enough leaks that it never hit the overboost condition at first. That explains some of the issues I was experiencing. The turbo itself, especially considering the age and overboost, really wasn't in as bad of shape as it could've been. That said the compressor wheel is worn and beaten up. There's some play, but not a ton. I'll have to decide what to do with it in the future. Maybe put it on the RX-7. :D

    I did some thinking about whether I wanted to put a different exhaust manifold on, or have this one ceramic coated. I decided on neither. The only different exhaust manifold available is expensive and, given that I'm not looking for more horsepower, I doubt would make that much of a difference.

    I also decided ceramic coating the existing manifold doesn't make sense to do. Reviewing some data I'd looked at before reminded me that ceramic coating doesn't do as much as header wrap, but does cost a lot more. So I will wrap the exhaust manifold before reinstalling it, which will help to keep more of the heat in the exhaust, which is good for turbo spool and reducing engine bay temps (that being something I try to attack, since with a rear rad all air is preheated by the engine before going through the radiator and intercooler).

    So now onto the turbo, I called up the company I was going to order it from and talked to one of their experts who deals with sizing these turbos for diesels all the time. He knew the application I was talking about, and suggested I go one size up on the compressor from what I was thinking and stick with the smaller size turbine wheel. Summary is it should keep quick spool (same or quicker than stock given the lighter weight and improved design components), more boost/airflow for the same fuel (which helps lower EGTs), overall good/happy things.

    Hopefully it shows up this week or next and I can start putting things back together. Exciting!
     
  34. Zeldman

    Zeldman Touchdown! Greaser!

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    Something is terribly, terribly wrong here... :lol::lol:
     
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  35. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    This engine is really pretty easy to work on. Definitely better than what I'm used to on your typical American vehicles. I do think Cat used good materials choices, which will probably be reflected in the cost of the new hardware I'm going to buy from them. Not because I need it (it was all reusable), but if I'm going to put this back together, I want it to come apart just as easily the next time (which is hopefully never).
     
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  36. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    iFlyNothing
    I went by the Cat dealer yesterday and picked up what will (hopefully) be virtually all of the parts I'll need to put this back together, plus a few extra items. I'm using all new gaskets and hardware. The gaskets were pretty much toast anyway (although the turbo to manifold gasket was in surprisingly good condition) but best to put it all together in such a manner that I hopefully never have to take it apart again. While there, I also picked up a couple of fuel filters (going to change that and I needed a spare), and a couple of new 180 degree thermostats. I had put in 190 degree thermostats when I redid the cooling system. However as I understand it, those thermostats start opening at 190 and are fully open at around 210. The 180 degree thermostats fully open around 200. With how my electric fan setup works (and the fact that some airflow ends up being required all the time), the goal with this will be to get full coolant flow at a lower temperature, which makes the cooling more effective.

    While changing the thermostats, I'm also going to put in some Amsoil Coolant Booster (@jesse insisted). I've never used this sort of thing before, but I figure it's worth giving a shot since this cooling system does need all the help with heat transfer it can get, which is the claimed benefit of it.

    I'll be wrapping the exhaust manifold before putting it back on the bus, and I've got the header wrap that I'll use for that.
     
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  37. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    iFlyNothing
    The new turbo showed up. It's shiny and definitely looks nicer than the old one!

    upload_2023-1-20_21-16-19.png

    It'll be a mostly bolt in replacement. I say mostly because a few things are off on it, but nothing really too significant. It's about 1/2" "taller" than the old turbo, which will move the air inlet for the compressor forward slightly. The exhaust looks like it will all bolt up just fine. The compressor outlet they machined down more than the original turbo, so I'll need a different coupler. Just little details, but overall good.

    The new turbo obviously is bigger (but essentially the same external dimensions). The compressor inlet is larger (as is the compressor itself). The T3 inlet flange is the same and I think both turbine housings are both 0.80 AR, but the exducer on the new turbo is a good bit bigger. I think this turbo should be more appropriately sized overall and provide less restriction, hopefully not adding too much lag. I doubt it will add much if any. Looking forward to getting this on.

    The exhaust manifold took a bit to get the flanges cleaned up enough to be ready, but I think it's ready to bolt on. So hopefully over the weekend or sometime next week I can get to that.

    Now I still have to figure out what to do with that old turbo. It really isn't in awful shape, there's a use for it somewhere.
     
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  38. SoonerAviator

    SoonerAviator Final Approach

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    Display name:
    SoonerAviator
    Wankle turbo?
     
  39. Ted

    Ted The pilot formerly known as Twin Engine Ted

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    I’d had the thought but it’s really too big. The only engine I have that it would be a decent size for is the 4.0 V8 in the Land Rover, which I’m swapping for the diesel. If I wanted to compound turbo that diesel it would work for an atmospheric side turbo in that application.
     
  40. Spring Ford

    Spring Ford Line Up and Wait

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    Jul 11, 2018
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    SpringFord
    OK. Juggling those components, the obvious answer is turbo V8 in the RX7.