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Got the engine started for the 3rd time yesterday.. got it idling for about 15mins, up to operating temperature and increasing the idle on the ECU from 650 up to about 2000rpm and holding for 30-45 seconds while the Dominator learns fueling for the those areas at no TPS.
Couple teething issues to work out:
1) had a minor coolant leak at the rad hose on the thermostat... I'm hoping that only requires the re-tightening that I can it afterwards
2) drive side turbo is leaking from turbine housing! Here are the details:
- no leaks the previous several times I had engine running (only ever for 30-60seconds, never reached operating temp @ idle)
- oil only started leaving the turbo once up to operating temp
- no oil was dripping onto the subframe, it was just smoking on the turbine housing
- Precision factory-installed oil restrictor fitting was still in place and sealed
- both oil feed lines are the same length and pull from the same location @ the pan
Possible causes:
- oil pan was actually over-filled by about 3/4" on the dipstick, unsure if this was backfilling the turbo drain and clogging up the CHRA
- turbo drain could be clogged (unlikely, yet to be checked)
- oil restrictor fitting is wrong size or improperly machining, allowing too much oil pressure into BB CHRA
- incorrectly installed or faulty turbine wheel shaft seal as delivered from the factory
Up until that stuff was discovered, I was super stoked on the idle of the thing, it should rowdy...
I have no idea.. cold oil pressure is 60psi and warming up to about 40-45psi depending where I set the idle... these turbos have spent a total of about 10mins at idle. Oil pressure has increased to mid-60's when warm at about 2500rpm the one time it was revved to that rpm and held there.. engine hasn't revved above that in its new configuration.
I'm trying to wrap my head around how this is possible.. I simply can't see how the -10AN turbo drain would be any restriction in its current form especially at idle, especially with "an oil restrictor" in place. The only thing that makes me second-guess myself is that the driver side (leaking) has 5/8" 0.043" stainless tube for the majority of the drain tube, however it's a minimum 30* downhill the whole way. The passenger side is -10AN Earl's UltraPro hose the whole way and didn't exhibit any signs of leaking. I was itching to dig into this yesterday but the engine didn't cool down enough before I had to leave the garage.
My plan of attack, in order of effectiveness is:
- don't touch any of the turbine housing bolts or CHRA... leave the current "leak" intact
- drain some oil to bring level down to "full" on dipstick (already done)
- undo turbo drain, use dulled aluminum filler rod to check for any obstruction, at same time inspect that turbo drain gasket isn't obstructing the drain flange.. re-attach drain
- restart engine, warm up, check for leak
- if leak is still present, remove CHRA+compressor from the turbine housing, leaving turbine housing attached on hotside/downpipe for convenience... visually inspect turbine wheel and axle shaft seal, inspect downpipe to see if oil has been blowing down it
EDIT:
Another thought I has was if this leaking oil is just assembly lube? I noticed that when I left the turbo's on their side in a box many months ago, there were some oil drips from what I presumed was axle/seal assembly lube, maybe after the turbo shaft had actually spun more than a couple rotations, some more assembly lube got flung out around the turbine housing & CHRA mating area. I didn't want to "stop" the leak by checking the tightness of the turbine housing cover bolts after this happened, but maybe they're allowing that assembly oil to drip out (although I didn't hear any exhaust leaks from the turbo).
Sorry to hear about the oil leak. Are you sure oil is coming past the turbine seal and into the housing then back out of the turbine housing where it is now dripping? Or could it be leaking from the inlet side on top of the center housing and just finding its way down around the outside of the housing? It is odd that oil would make its way inside of the turbine housing and manage to pool and seep to the outside of the turbine housing instead of just being swept along in the exhaust stream. I would look at the oil inlet carefully before getting too caught up in potential internal leaks.
Originally Posted by frojoe
Possible causes:
- oil pan was actually over-filled by about 3/4" on the dipstick, unsure if this was backfilling the turbo drain and clogging up the CHRA
- turbo drain could be clogged (unlikely, yet to be checked)
- oil restrictor fitting is wrong size or improperly machining, allowing too much oil pressure into BB CHRA
- incorrectly installed or faulty turbine wheel shaft seal as delivered from the factory
Assuming oil is escaping past the turbine seal and then making its way back out, the first 3 potential causes are all based on excess oil and/or crank pressure building up in the housing. If that's the case, you might also see oil leaking into the compressor / cold side of the system. Might be worth opening one of the connections to see if you have oil inside leading into the intercooler. If so, you can focus on this family of potential causes. If not, it doesn't necessarily rule these causes out, but you might be more inclined to disassemble the CHRA and inspect the turbine oil seal.
Thanks for that info Clint, I'll read thru what Garrett has to say. I spent a good 5 minutes inspecting the turbo top and bottom sides as best I could with a flashlight and a pen mirror, since things were pretty damn hot still... I really couldn't see anything at all other than the drip in the pics, which to the best of my thinking appears like it is to be originating from underneath the turbine housing bolt head. It was impossible to take a pic of, but the top side of that bolt head between it and the underside of the CHRA was clean and dry, so I think that rules out oil dripping on to of the bolt head from the CHRA. The entire CHRA was dry as far as I could see..
I aim to go back out there one night soon and give it a closer inspection with it cold. Good call on pulling the compressor elbow off to inspect.
If you end up needing to pull the CHRA apart, it looks like you can leave the turbine housing installed and leave all the hot piping alone, detach the CHRA from the turbine housing, then just pull the CHRA from it. If oil is leaking that badly from outside the housing, you probably have a substantial pool of oil inside behind the heat shield which will spill out as you remove it. Some oil is probably also sitting inside the housing itself. It's odd for a brand new turbine seal to fail. It could be missing entirely or they might have mistakenly installed the wrong seal. I can't see why your drain or feed lines would be causing this - everything seems sized properly. Maybe a combination of crank pressure and high oil level could be causing problems, but my money is (currently) on a turbine seal issue.
I disassembled and assembled a lot of turbochargers when I briefly worked at Garrett. They aren't that hard to pull apart just make sure you have the compressor wheel match marked with the end of the shaft so you can keep things in balance when you reassemble.
Regarding assembly lube, I suppose it's possible the CHRA had some amount of oil in it that subsequently pooled behind the turbine heat shield and is now finding its way out. This seems like a very remote / unlikey possibility.
Regarding possibility of assembly oil... if it is indeed that, then I'm still confused how come the oil could possibly be managing to make its way from shaft seal -> bottom of turbine housing -> past housing seal to CHRA -> dripping out?
Regarding possibility of oil pooling inside the hotside.. the pre-turbo hotside piping is angle up as you backtrack towards the engine, and the lowest pre-turbo hotside point is at the T3 flange, so there shouldn't be any oil running back to and pooling in the exhaust manifolds.. and checking for internal oil pooling would be as simple as pulling the housing off the hotside T3 flange.
Regarding inspecting the CHRA, I would do exactly as you mention by leaving the turbine housing on the car, maintaining all those exhaust connections, and just remove the CHRA+compressor.
I'm a bit apprehensive to tear apart the CHRA beyond just a visual inspection around the shaft seal... I will see if it ends up coming to that... I would worry about messing up the balance or axle nut torque values, even though in theory you're right, it's a simple axle/nut assembly.
Unfortunately you wont be able to do much inspection without disassembling the rotor. The heat shield and the turbine wheel are going to block your view of the seal. Even if they didn't the seal would be buried in the housing. You might be able to confirm oil is coming from that general area, but that wouldn't tell you for sure if the seal was bad or if you had some other oiling pressure issue.
As far as theory on the simple axle nut assembly, it really is that simple. I was trained by a many-decades veteran engineer at Garrett on how to tear down and assemble these things. Even did balancing work myself. With thru-shaft compressor wheels it really is as simple as lining up orientation on the shaft between assembly/disassembly. During balancing sometimes I would loosen and reorient the wheel to optimize balance first, then cut material as needed and match mark the wheel to the shaft. Once balanced I would assemble based on match marking. The more challenging ones are the integral-hub/threaded compressor wheels where you really don't get much choice on orientation and you have to rely on angle consistency from assembly torque. My only fear with you taking it apart would be voiding a warranty - if you have such a warranty then by all means send it back and have them do this for you. I probably assembled around 100 turbochargers with zero failures. Most of those involved a novel turbocharger design with two compressor wheels (one aluminum, one titanium) which was quite a balancing act (pun!). On those both wheels got matched marked with the shaft as they went on and were reassembled the same away after balancing. For what it's worth I also played a significant part in designing the bearing systems on said novel turbocharger prototypes. I'm not sure if the excellent bearing system design compensated for poor assembly practice or the excellent assembly practice compensated for the poor bearing system design
Torquing those nuts or wheels (if the hub/thread is integral) is very important. Use a smooth consistent motion up to the torque value. Never start/stop or slow as you move up to the target torque. You can do it. No special tools required.
With regards to the pre-oil theory (which I think is far fetched but very remotely possible), if the turbo was stored sitting off-angle on the face of the turbine housing (i.e. shaft running slightly off vertical with the housing sitting down), it is possible that oil in the center housing would leak past the turbine seal ring gap and collect inside the heat shield. It wouldn't store a lot of oil though.
That's all very interesting Clint.... I sent an email off to the vendor I got the trubo's from, who in the past has been exceptionally helpful... so we'll see what the test/inspect recommendations are, or if I should just send the turbo back (last resort due to shipping weight/expense). I'll still do my inspection and see if I can see any issues with the drain line and flow.
Congrats on the motor firing up! That idle from the rear sounds really mean. Hopefully you are able to figure out the leaking turbo in time to get some cruising in this year.
This past weekend I completed the tailpipes and got the car on the ground in preparation of a maiden voyage!
I drove it forward out of the garage under its own power (yay!) BUT I couldn't get it into reverse gear no matter how hard I tried.
I started troubleshooting by trying to put it in reverse with the car off, rocking the car forward/back with my foot out the door... no luck. I was able to get it into what felt like the reverse gate since I could feel the noticeable increase in force required at the stick as I was manually overriding the coil spring in the reverse lockout assembly.
With this, I thought.. well maybe there's something screwy with the lockout solenoid, so I jacked the car up, loosened the solenoid off and pulled it out of the transmission about 1/4".. that should've been enough to move the stick over well into the reverse gate with minimal force on the lockout solenoid coil spring... nope no reverse gear.
I then thought that the McLeod short throw aftermarket shifter might be limiting things, so I pulled it out and put it on the bench to measure its angular range... 18deg to the left and 23deg to the right... I thought surely that would be enough throw to engage the reverse gate fully. Threw the McLeod shifter back on and no matter how I adjusted the baseplate... wouldn't engage reverse... ****.
As a last ditch effort I borrowed back the stock T56 shifter form the buddy I sold the old trans setup to, and installed it... success! Apparently both the Mcloed shifter and the solenoid were limiting the reverse gate throw.
It appears that if the lockout solenoid is energized and its pin is out of the way, the coil spring plunger assembly in the lockout housing DOES actually move out of the way enough to allow reverse to be accessed on a retrofitted Magnum... but if no electronics are hooked up and the lockout pin is in place, just manually overpowering the coil spring will NOT allow enough plunger travel to go deep enough into the reverse gate in order to shift it into reverse. Between the regular T56 and the Magnum there must be slightly different selector travel on the shifter rod, or maybe tighter/better tolerances on the Magnum, that disallowed me to overpower the spring and get all the way into the reverse gate, where I was able to do that on the old T56. I'm guessing just about everyone that has paid extra for a 4th gen retrofitted Magnum aren't affected by this because they're throwing the trans into an f-body and hooking up the wiring to the lockout solenoid, and the solenoid correctly working allows full functionality.
Anyways, I made a pair of internal spacers inside the lockout housing that shuttles the coil spring plunger assembly outboard enough to allow the full plunger travel I need in order to move fully into the reverse gate.
Here is the assembly as removed, with the plunger bottomed out. This situation below is with the solenoid pin in place (no energized or removed) capturing the bottom seat for the plunger coil spring, and the coil spring is in full coil bind. The plunger is sticking out about 1/8", which is about the amount of extra travel I need in order to move fully into the reverse gate...
This shows the solenoid pin in the non-energized state, just hanging out as a ledge to capture the bottom of the plunger coil spring assembly..
Here is the view that the solenoid has of the bottom of the coil spring plunger assembly, you can see the steel spring retainer plate that the pin would support...
Pretending the solenoid is energized, allowing the spring plunger assembly to shuttle by freely, this is what the coil spring assembly looks like...
This shows the plunger being flush with the housing if the solenoid is energized like in the above pic...
So I made a bottom spacer to lower the resting position of the coil spring plunger assembly, including a chamfer to move the solenoid pin out of the way during assembly...
This height spacer blocks the solenoid pin out of the way so it's no longer the deciding factor of where the coil assembly sits in the lockout housing...
This shows the coil spring assembly bottomed out at full coil bind with the new spacer I machined, gaining the 1/8" of extra travel I needed...
Shuttling the coil spring assembly further into the housing meant that there was slack to take up between the plunger in its resting position and the internal snap ring that keeps everything together....
Just made a steel spacer to take up the slack between the plunger and the internal snap ring...
And full reassembled, waiting to go back in the car and get test driven!...
How is the solenoid powered? You know you can activate it with the Dominator and program it to work like OEM if you also have a speed input into the Dominator. Mine is set-up this way and the solenoid is energized at speeds below 5 MPH...
How is the solenoid powered? You know you can activate it with the Dominator and program it to work like OEM if you also have a speed input into the Dominator. Mine is set-up this way and the solenoid is energized at speeds below 5 MPH...
Andrew
I imagine it's just a switched 12V and ground, or vice versa.. but I'm not 100% sure. While you are right and in theory that's the proper way to go about it, I'm just used to physically overriding the solenoid. And since it was out anyways, it was just simpler for me to spend a few minutes machining some simple parts to mechanically fix the problem, versus spending the extra time running more wires thru the firewall to the trans and then programming on top of that.
I'm looking at this the way you were probably looking at my TH400 rebuild. I haven't got a damn clue what I'm looking at, but I get the impression you're on your way to driving the car soon and that's a good thing. Have you let her idle long enough to see if that oil leak self-resolved?
I imagine it's just a switched 12V and ground, or vice versa.. but I'm not 100% sure. While you are right and in theory that's the proper way to go about it, I'm just used to physically overriding the solenoid. And since it was out anyways, it was just simpler for me to spend a few minutes machining some simple parts to mechanically fix the problem, versus spending the extra time running more wires thru the firewall to the trans and then programming on top of that.
So what you did there completely eliminated the reverse lock out function? Depending where your auxiliary I/O on the harness is located, no extra wires are needed. Is the 8 cavity metripack connector in the engine bay?
I'm surprised that you have access to all this functionality that the Dominator offers, but you're not taking advantage of it. Next thing you'll tell me is that you got an auxiliary boost controller...lol
I'm looking at this the way you were probably looking at my TH400 rebuild. I haven't got a damn clue what I'm looking at, but I get the impression you're on your way to driving the car soon and that's a good thing. Have you let her idle long enough to see if that oil leak self-resolved?
It's a manual-transmission thingy, don't worry about it Clint! I'm planning on taking it for a test drive tonight. No I haven't idled it long enough to see if the oil leak develops again.
Originally Posted by Project GatTagO
So what you did there completely eliminated the reverse lock out function?
Andrew
I've "eliminated" the electrical function of the reverse lockout by preventing the solenoid pin from moving anywhere other than its current fully-depressed position... but the mechanical coil spring is still in the lockout assembly so there is still a measure to prevent accidental shifts into reverse instead of 5th.
So what you did there completely eliminated the reverse lock out function? Depending where your auxiliary I/O on the harness is located, no extra wires are needed. Is the 8 cavity metripack connector in the engine bay?
I'm surprised that you have access to all this functionality that the Dominator offers, but you're not taking advantage of it. Next thing you'll tell me is that you got an auxiliary boost controller...lol
Andrew
Haha.. there is no more factory Holley 8 pin I/O connector... I've removed all Holley loom, snipped most wires to length, rebuilt my harness with new loom branches, etc and used bulkhead grommets that I machined which are located behind the intake manifold. To add electrical functionality would involve pinning out two more wires, adding them to the harness loom, fishing them thru the bulkhead connectors behind the intake and then routing down to the tailhousing. After that, I would still be 100% relying on the lockout to function properly in order to access reverse. Say the solenoid failed on me, I wouldn't be able to overpower the plunger spring and access reverse because of the physical/mechanical limitations I listed above. What I did instead is just modify the mechanical aspect of it so that there are never any electronics to fail, and I can continue shifting into reverse how I've always done in this car.. by simply overpowering the lockout spring. I'm a huge fan of electronics and using technology to my advantage.. but I also try to think ahead and avoid doing things that could cause extra brain damage.
Glad it was an easy fix, though I thought you said your lockout solenoid was bypassed? I don't have the room in my tunnel for the assembly, so I cut the housing and eliminated the solenoid completely. Using a weaker-than-stock spring I found on eBay, it's more like an older trans in its reverse operation now.
Glad it was an easy fix, though I thought you said your lockout solenoid was bypassed? I don't have the room in my tunnel for the assembly, so I cut the housing and eliminated the solenoid completely. Using a weaker-than-stock spring I found on eBay, it's more like an older trans in its reverse operation now.
The lockout solenoid/assembly was never bypassed with the previous T56, or the initial install of this 4th-gen-tailhousing-swapped T56 Magnum... I previously had just overpowered the lockout plunger and spring. But now, with my mod, the solenoid pin is physically moved out of the way thus making the solenoid useless, and the solenoid body is essentially still there just to seal the threads and keep the system closed.