Engine breakdown assessment
#1
Engine breakdown assessment
Engine blew the rear rotors oil seals apart. The rear rotor lobe on the essentric shaft has one of the oil passages plugged with a hunk of metal... which in turn more than likely screwed the rear rotor bearing.... looking for some advice.
#2
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that is weird. i would measure up the rotor, and if there is nothing else wrong with it, change the bearing. replace the shaft. um i would have a really really hard look at the rest of the oiling system.
obviously that is not very normal, but it looks like you caught it before it really went bad
obviously that is not very normal, but it looks like you caught it before it really went bad
#3
that is weird. i would measure up the rotor, and if there is nothing else wrong with it, change the bearing. replace the shaft. um i would have a really really hard look at the rest of the oiling system.
obviously that is not very normal, but it looks like you caught it before it really went bad
obviously that is not very normal, but it looks like you caught it before it really went bad
#7
Old [Sch|F]ool
FWIW, one time I found my front cover O-ring in my oil filter pedestal. Not entirely sure how it made it past the oil cooler.
That was the last 13B that I built not using an RX-8 front cover gasket.
(My 12A has the gasket/O-ring combo, because I built it for a class where no internal engine mods are allowed, and I didn't want to risk getting protested over something stupid)
That was the last 13B that I built not using an RX-8 front cover gasket.
(My 12A has the gasket/O-ring combo, because I built it for a class where no internal engine mods are allowed, and I didn't want to risk getting protested over something stupid)
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#8
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probably not! so when we were in the office the warranty guy was over the cube wall, and i guess timing chains are hard. he would always have the front of some engine (or rear if its a Ford), laid out on a desk, and when the timing chain breaks it really does a lot of damage. since its a warranty claim, someone bought a tensioner or something, and then is claiming the whole front of the engine, so its kind of a big deal. the guy spends a lot of time looking at stuff (step one is to make sure they actually bought the thing from us!), but when the whole engine is shrapnel its really hard to tell what came first.
you really need to be like Sherlock Holmes and look at everything, usually there is only one version that fits the facts, but sometimes you just can't tell
you really need to be like Sherlock Holmes and look at everything, usually there is only one version that fits the facts, but sometimes you just can't tell
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peejay (10-14-21)
#9
Ok guys.... good thoughts here and trying to solve the puzzle..... I'm trying to understand the path of the oil thru the entire system.... key clue here I believe is the engine oil was barely used. Nearly clear. What about the the possibility of something being stuck in the new oil filter when the oil was changed more than likely less than 200 miles before d- day? Would that have made the journey to its final place easier than it being introduced thru the oil fill tube? Purged the e-shaft and all ports were fully clear and unobstructed. Any other thoughts to look into before I go crazy on cleaning the crime scene? Side note is the rear rotors front facing oil control rings were the ones totally fried.
#11
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Ok guys.... good thoughts here and trying to solve the puzzle..... I'm trying to understand the path of the oil thru the entire system.... key clue here I believe is the engine oil was barely used. Nearly clear. What about the the possibility of something being stuck in the new oil filter when the oil was changed more than likely less than 200 miles before d- day? Would that have made the journey to its final place easier than it being introduced thru the oil fill tube? Purged the e-shaft and all ports were fully clear and unobstructed. Any other thoughts to look into before I go crazy on cleaning the crime scene? Side note is the rear rotors front facing oil control rings were the ones totally fried.
the pic is a little weird, apparently the translator was from the other side of the equator, or had neck problems or something
#12
Rotary Enthusiast
That's my new favorite diagram, but it's giving me neck pain
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risingsunroof82 (10-15-21)
#13
Fair enough. 😆 here's some wear on the rear iron that was involved in the rear rotor failure.... is this wear in a critical area (which i know any chrome lining areas are) and non usable? I'm gonna guess this is damage from a combustion leak or something that caused the plating to "pit"? And the lower half of the plating looks like it's thin as well.
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the side seal lands (green) are showing contact with the iron, not a huge deal here, although measure the width of the groove
the red arrows are where the rotor was hitting the iron, so you need to measure the rotor land protrusion
the red arrows are where the rotor was hitting the iron, so you need to measure the rotor land protrusion
#23
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So would the contact be due to rotor bearing or e- shaft? Front and rear mains are in relatively good shape.
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peejay (10-18-21)
#24
Old [Sch|F]ool
Looking at that '83-85 12A diagram. Bypass valve in the beehive. Does that mean it is in fact thermostatically controlled?
If so... Verrrrrry interesting!
If so... Verrrrrry interesting!