1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Seized up at 95 mph

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Old 04-13-09 | 10:13 AM
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Seized up at 95 mph

For all you who did not know what happens to the rotary when a water jacket or O-ring ( I suspect ) lets go, I give you my newest experience to hopefully learn a lesson easier than I did. So the story goes like this... I changed the oil in the RX on Saturday afternoon (1st time out of the garage for the season) then went for a short cruise, came back, checked the oil and noticed some condensation on the fill tube. Now I have always had a little condensation but this time it seemed to be a little more. Sunday I check the oil again and all seems find, except for the condensation on the fill tube. So I head to the gas station, fill it up and check everything over and off I go. I am cruising the interstate at 75 -80 for aprox. 45 miles and all the time watching gauges. I notice as I accelerate and open the secondarys that the oil pressure drops slowly about 5 psi and as I let off the gas it raises back up 5 psi. I come to a point where the highways merge and cross the river ( for the locals, M-6/ I-96 interchange over the thornapple river headed east ) so I accelerate up around 80 to merge, as I merge it's clear of traffic so i figure let's give it a little and have some fun ( all the while watching the gauges ). All of a sudden, with no warning from the gauges, the car locks!!!! Motor, tranny, rear end all simultaneously. We all know what happens when tires lock at speed!!! The rear end comes out and I proceeded to spin three times before resting in the ditch 10' off the interstate facing the same direction. No harm to the exterior of the 84!! Motor, flywheel and tranny are needing some work now!!!
Old 04-13-09 | 10:17 AM
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Originally Posted by seldawg
For all you who did not know what happens to the rotary when a water jacket or O-ring ( I suspect ) lets go, I give you my newest experience to hopefully learn a lesson easier than I did. So the story goes like this... I changed the oil in the RX on Saturday afternoon (1st time out of the garage for the season) then went for a short cruise, came back, checked the oil and noticed some condensation on the fill tube. Now I have always had a little condensation but this time it seemed to be a little more. Sunday I check the oil again and all seems find, except for the condensation on the fill tube. So I head to the gas station, fill it up and check everything over and off I go. I am cruising the interstate at 75 -80 for aprox. 45 miles and all the time watching gauges. I notice as I accelerate and open the secondarys that the oil pressure drops slowly about 5 psi and as I let off the gas it raises back up 5 psi. I come to a point where the highways merge and cross the river ( for the locals, M-6/ I-96 interchange over the thornapple river headed east ) so I accelerate up around 80 to merge, as I merge it's clear of traffic so i figure let's give it a little and have some fun ( all the while watching the gauges ). All of a sudden, with no warning from the gauges, the car locks!!!! Motor, tranny, rear end all simultaneously. We all know what happens when tires lock at speed!!! The rear end comes out and I proceeded to spin three times before resting in the ditch 10' off the interstate facing the same direction. No harm to the exterior of the 84!! Motor, flywheel and tranny are needing some work now!!!
WOW...quite a story. Hopefully the engine is the only thing fubar'd. The tranny and rear end should have survived.
Old 04-13-09 | 10:18 AM
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Damn dude, sorry to hear that. Do you have another motor to put in? Where are you located around the Detroit area?
Old 04-13-09 | 10:20 AM
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glad you're safe, did you try the clutch? i'm sure it would have saved you from some damage
Old 04-13-09 | 10:30 AM
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Sorry to hear of your loss man. Glad to hear you're okay. Now you have to get a new motor installed before the May 16/17 Meet/Autocross.



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Old 04-13-09 | 10:39 AM
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scary
Old 04-13-09 | 10:47 AM
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Originally Posted by Kentetsu
Sorry to hear of your loss man. Glad to hear you're okay. Now you have to get a new motor installed before the May 16/17 Meet/Autocross.



.
Agreed. If you need a hand early May, I will be more than happy to help you put in a new motor. I have a 68k mile SA core sitting at my Grandpa's (unknown condition) that, if needed, we can drop in to see if it'll work. No charge for the motor if it doesn't run, we'll just pull it so I can disassemble it to see why it didn't want to start.
Old 04-13-09 | 11:17 AM
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ill help if you need it, let me know! i dont have another engine as kentetsu took my last spair
Old 04-13-09 | 01:04 PM
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+1 to the list of things not to ignore... though just losing a water seal shouldn't cause a lock without first seeing a temperature spike. Even a catastrophic water loss will take a little time to let the car get hot enough to sieze. Sounds more like something has broken loose and blocked rotation (oil pump or inside front cover items, perhaps?)... but...

I had a complete seizure in my 91 Camaro once (on the Hollywood freeway at rush hour, no less.) Got sidelined OK (scary fishtail until I got out of gear), but engine would not crank at all. Trying to start would just lock the starter and dim the lights.

Long story short, it was the alternator that had frozen. The serpentine belt was more than strong enough to 1) stop the engine dead at low highway speed, and 2) prevent the starter from turning the engine at all.
Old 04-13-09 | 01:11 PM
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west michigan whitey
Old 04-13-09 | 01:13 PM
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threw in the clutch thunk. pretty sure that slowed me some. Thank god for a low center of gravity!!
Old 04-13-09 | 01:16 PM
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Have a motor and trans in the garage that was going to build for supercharger. Will probably put that in for the season while I tear down and rebuild the seized motor for a supercharger. Definetely will call on you guys if I need some help so thanks for the offers. I know the outer ring on the flywheel spun cuz I can hear that. Lets hope thats as far back as it goes!!
Old 04-13-09 | 02:00 PM
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Originally Posted by DivinDriver
+1 to the list of things not to ignore... though just losing a water seal shouldn't cause a lock without first seeing a temperature spike. Even a catastrophic water loss will take a little time to let the car get hot enough to sieze. Sounds more like something has broken loose and blocked rotation (oil pump or inside front cover items, perhaps?)... but...

I had a complete seizure in my 91 Camaro once (on the Hollywood freeway at rush hour, no less.) Got sidelined OK (scary fishtail until I got out of gear), but engine would not crank at all. Trying to start would just lock the starter and dim the lights.

Long story short, it was the alternator that had frozen. The serpentine belt was more than strong enough to 1) stop the engine dead at low highway speed, and 2) prevent the starter from turning the engine at all.
I've seen that before on a GM car, the alternator froze so hard and the tension on the belt was enough to prevent the engine from cranking over. Almost mis-diagnosed it as an engine related issue due to my inexperience at the time.
Old 04-13-09 | 03:00 PM
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A complete water failure shouldn't lock up the engine at all. Not unless you way overheated it and something broke. The drop in oil pressure leads me to believe the failure was oil system related. Broke a bearing, stationary gear, complete catostrophic water failure shouldn't lock up your engine. It's pretty damn hard to hydro lock a rotary. Worse case it blows the **** out of an apex seal, but then you'd lose compression not lock it up. I can't imagine the engine injesting 1.3L of water fast enough to lock it up.
Old 04-13-09 | 03:54 PM
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the 5psi of oil pressure should have been the first clue that you should have taken the car back home and troubleshot the problem. glad you are ok though. keep us posted on the progress.
Old 04-13-09 | 04:04 PM
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Originally Posted by Hyper4mance2k
A complete water failure shouldn't lock up the engine at all. Not unless you way overheated it and something broke. The drop in oil pressure leads me to believe the failure was oil system related. Broke a bearing, stationary gear, complete catostrophic water failure shouldn't lock up your engine. It's pretty damn hard to hydro lock a rotary. Worse case it blows the **** out of an apex seal, but then you'd lose compression not lock it up. I can't imagine the engine injesting 1.3L of water fast enough to lock it up.
agreed! actually dont think you can hydrolock it if you tried
Old 04-13-09 | 05:39 PM
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I got $5 on oil pump mech failure under the front cover. Hedged with $3.50 on a spun bearing.
Old 04-13-09 | 06:25 PM
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What's the over under on a stat gear? Ohh I bet odds would pay well if you bet on a broken eshaft. If he still had oil pressure and it locked up I willing to bet the pressure was dropping because a bearing somewhere was spinning away. Then bang it pops out, jams sideways, and locks up. You can run a rotary on little to no oil pressure for quite a while due to the massive bearing size, as long as they stay mounted in the rotor and stat gears. Once they spin say good buy to reusing anything in that engine. lol
Old 04-13-09 | 09:15 PM
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you have to wonder if its related to the oil change.

we did have a drain plug come out of the race car once, although the oil comes out slow enough you have a long time to shut it off, even at 95....
Old 04-14-09 | 06:42 AM
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Originally Posted by j9fd3s
agreed! actually dont think you can hydrolock it if you tried
well i thought the same thing guys but when i popped the hood water was steaming out of the gasket between the front cover and first rotor housing. All the way around the housing!!! (will take some pics) Also, consider I just did a fresh oil change and when I pulled the dipstick the level is way up past the proper mark, full of water. So until I disassemble I won't know for sure, but at this point it is looking like a for sure hydro lock!!
Old 04-14-09 | 06:44 AM
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Originally Posted by j9fd3s
you have to wonder if its related to the oil change.

we did have a drain plug come out of the race car once, although the oil comes out slow enough you have a long time to shut it off, even at 95....
Then there would not be any fluid on the stick!! The motor would be empty or damn close!!
Old 04-14-09 | 06:48 AM
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Originally Posted by mazdaverx713b
the 5psi of oil pressure should have been the first clue that you should have taken the car back home and troubleshot the problem. glad you are ok though. keep us posted on the progress.
that was for sure the first clue, but I still would not have made it home. I watch the gauges close and that was the first time it ever dropped under normal acceleration. Once the oil pressure was observed, I was granted only 3 more miles before she went. Next time I see a slight change you can bet your *** I will be pulling off the road and trailering her home.
Old 04-14-09 | 06:53 AM
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Originally Posted by Hyper4mance2k
What's the over under on a stat gear? Ohh I bet odds would pay well if you bet on a broken eshaft. If he still had oil pressure and it locked up I willing to bet the pressure was dropping because a bearing somewhere was spinning away. Then bang it pops out, jams sideways, and locks up. You can run a rotary on little to no oil pressure for quite a while due to the massive bearing size, as long as they stay mounted in the rotor and stat gears. Once they spin say good buy to reusing anything in that engine. lol
I suppose that is possible due to the fact that it was instantly locked. No spike in temp, no severe drop in oil pressure. But how did the water fill the oil pan then. Would the bearing have caused it too spin and bust a water jacket possibly!!! When I say instant I mean instant too. Driving then sliding in a tenth of a second!!!!At this point I hope it is hydrolock versus a spun bearing. Sounds like that may be a bit more salvageable !!!!
Old 04-14-09 | 06:58 AM
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Originally Posted by DivinDriver
I got $5 on oil pump mech failure under the front cover. Hedged with $3.50 on a spun bearing.
Front cover seems to be the area too. All the water (steam) was from between the front cover and front rotor housing. Hmmmmmmm!
Old 04-14-09 | 08:54 AM
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Sounds like a mechanical lock more than a hydraulic one. I think with the car traveling at 90mph it would have just busted all 6 apex seals rather than lock the engine.


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