186000 miles 2007 teardown-for your viewing pleasure
#1
77 cylinders, 4 rotors...
Thread Starter
186000 miles original engine 2007 teardown-for your viewing pleasure
Housing that got annihilated by a broken apex seal at 186000 miles
Rotor from same housing. Of course, it was the rear rotor.
Rotor face. Note how clean it is. Not just from shrapnel flying around in there, because the front rotor is equally clean.
Rotor from same housing. Of course, it was the rear rotor.
Rotor face. Note how clean it is. Not just from shrapnel flying around in there, because the front rotor is equally clean.
Last edited by kevink0000; 04-23-2018 at 11:18 AM. Reason: add to title
#3
77 cylinders, 4 rotors...
Thread Starter
more pics
The kind of damage you would expect. Note how clean the exhaust port is. Front housing looks equally clean.
More of the same
More of the same
#4
77 cylinders, 4 rotors...
Thread Starter
Now for the good parts
Bearing. in excellent condition.
E shaft in excellent condition. That is just oil film you see, not gouges.
E shaft in excellent condition. That is just oil film you see, not gouges.
#5
77 cylinders, 4 rotors...
Thread Starter
Housing
Front housing. Chatter marks, and wear all the way around. That is the steel liner you see by the oil hole. Chrome is gone there.
Front housing.
Front housing.
#6
77 cylinders, 4 rotors...
Thread Starter
More to come.
#7
77 cylinders, 4 rotors...
Thread Starter
Housing
"Power stroke" area of housing. Steel liner showing at edge.
#8
77 cylinders, 4 rotors...
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Housing
Same housing closeup
#9
77 cylinders, 4 rotors...
Thread Starter
Housing
Front iron. About .002 max step wear.
#12
77 cylinders, 4 rotors...
Thread Starter
more pics
Front rotor. Again very clean. Shows recent damage, which I think came through the intake manifold when the rear rotor's apex seals let go. I found fine pieces of metal in the manifold itself.
#13
77 cylinders, 4 rotors...
Thread Starter
more pics
Front rotor showing cleanliness and recent damage. All seals were intact on this one when engine was disassembled. I believe there was distribution of fragments from the rear rotor to the front through the intake manifold. I found lots of metal shards at the rear rotor's intake port, and some further down the port on the way to the front rotor,
#14
77 cylinders, 4 rotors...
Thread Starter
front bearing
That is not a scratch it is just some hair or something. This is the front bearing. It looks better in person.
#15
77 cylinders, 4 rotors...
Thread Starter
exh port front rotor
#16
///// Upscale Zoom-Zoom
I'm also interested in the premix amount, oil type, and oil change interval info. Thanks for sharing.
#17
77 cylinders, 4 rotors...
Thread Starter
PO said he used Castrol gtx5-20, changed oil between 3-5k miles, and the engine used a quart or so between changes. I don't think he premixed, and I have asked him for more info on his driving habits. It was registered in Southern California for its entire life before I got it.
He used FL22 coolant based on what I saw in the engine, which kept the metal corrosion free. Here is a previous post.
I will have more pictures up soon.
Lack of lubrication, yes. I have a 186000 mile DD original 2007 engine taken apart in my garage currently. The PO kept it well, and used GTX 5-20 exclusively, which seems to me based on this engine to be a better oil than I thought it was. The bearings look great, the innards are very clean, but what killed it was lack of lubrication to the apex seals in my opinion. The side seals all had large clearances to the corner seals (.018- .022"), but minimal wear on their faces, and minimal wear on the front irons. The engine ate an apex seal on the rear rotor ultimately, but prior to that compression on both rotors was low, the engine would barely start with a 13t starter, hot or cold. I believe from the wear I see that the apex seal fatigued from excessive "fretting" type wear against the rotor groove and/or the side piece, and then cracked.
The undamaged but worn front rotor housing had evidence of metal to metal contact (very shiny mirror finish in many areas) from the apex seals. No chrome flaking on this engine. The apex seals themselves appear to be the primary wear item as engineered originally, as they are much softer material than what they ride in and against in the engine. They were worn in the middle portion more than the sides, which others have posted, likely from heat related "banana" deforming. Unfortunately, from that fretting wear I described, it looks like the seals are basically kept "dry" in the grooves, with very little in the way of lubrication at that point with the stock injection amounts.
It looks like the stock oil amount and "aiming" was adequate to keep the side seals/irons from wearing excessively, but the apex seals suffered. Again when the forum rules allow me to post the engine pics, I will do so. I think they will be interesting given the mileage of the engine.
He used FL22 coolant based on what I saw in the engine, which kept the metal corrosion free. Here is a previous post.
I will have more pictures up soon.
Lack of lubrication, yes. I have a 186000 mile DD original 2007 engine taken apart in my garage currently. The PO kept it well, and used GTX 5-20 exclusively, which seems to me based on this engine to be a better oil than I thought it was. The bearings look great, the innards are very clean, but what killed it was lack of lubrication to the apex seals in my opinion. The side seals all had large clearances to the corner seals (.018- .022"), but minimal wear on their faces, and minimal wear on the front irons. The engine ate an apex seal on the rear rotor ultimately, but prior to that compression on both rotors was low, the engine would barely start with a 13t starter, hot or cold. I believe from the wear I see that the apex seal fatigued from excessive "fretting" type wear against the rotor groove and/or the side piece, and then cracked.
The undamaged but worn front rotor housing had evidence of metal to metal contact (very shiny mirror finish in many areas) from the apex seals. No chrome flaking on this engine. The apex seals themselves appear to be the primary wear item as engineered originally, as they are much softer material than what they ride in and against in the engine. They were worn in the middle portion more than the sides, which others have posted, likely from heat related "banana" deforming. Unfortunately, from that fretting wear I described, it looks like the seals are basically kept "dry" in the grooves, with very little in the way of lubrication at that point with the stock injection amounts.
It looks like the stock oil amount and "aiming" was adequate to keep the side seals/irons from wearing excessively, but the apex seals suffered. Again when the forum rules allow me to post the engine pics, I will do so. I think they will be interesting given the mileage of the engine.
__________________
#18
77 cylinders, 4 rotors...
Thread Starter
Also, car is 100% stock. Original radiator, with no foam left! Had the MSP16 done in 2008.
#19
77 cylinders, 4 rotors...
Thread Starter
better ex port pic
#20
77 cylinders, 4 rotors...
Thread Starter
front cover.
Like new. I have a different view of GTX 5-20, I can tell you that.
#21
///// Upscale Zoom-Zoom
Many thanks for the information. I'm going to continue more frequent OCI of about 1000-1500 using Wally World's finest 5W30 and continue premixing at > 0.25 oz/gal with a HQ 2-cycle premix that's rated for JASO FC or FD (not TCW3). Currently using Citgo Mystik 2-cycle JASO FD since it's readily available locally for $18/5 qt. bottle.
#22
77 cylinders, 4 rotors...
Thread Starter
apex seals
Groove worn in apex seal from rotor. This is the biggest wear item in this particular engine by far.
#23
77 cylinders, 4 rotors...
Thread Starter
apex seal
#24
77 cylinders, 4 rotors...
Thread Starter
apex seals against a straightedge with light behind
You can see how much the seal center section is worn here. The light is coming through the gap between the seal face and a straightedge.
#25
77 cylinders, 4 rotors...
Thread Starter
apex seals against a straightedge with light behind