DGRR 2011 Carnage
01-05-12, 07:58 PM
#1
DGRR 2011 Carnage
So for those of you who don't know, I had a bit of motor trouble this past year. After my first run through The Dragon at DGRR2011, I knew I had a hurt motor, but I didn't know how bad it was until today.
Symptoms: NO power. I ran it above 7k in 2nd just to get up the hill to Nantahala Village, and was running in 3rd gear above 7k during the Friday Morning Fun Run. I did a quick and dirty compression check Thursday night at the cabin, and found the rear rotor was missing an apex seal. Puff-nothing-nothing-puff-nothing-nothing.
I've had some issues getting the flywheels off of the two motors I popped this year, so when I was in the garage today I hit both of them 3 or 4 times, and to my surprise the flywheel came off of the DGRR motor. Three irons, one rotor, and the e-shaft where salvageable. The rear rotor has some gnarly damage to it, including indentations, a mangled apex seal groove, and a piece of an apex seal embedded into the rotor face. The rear housing was gouged to hell, which I was expecting.
What I wasn't expecting was to find mass chrome flaking (110k motor out of an '85) and a BROKEN apex seal on the front rotor. Here are the pictures:
Front rotor broken Apex seal:
Front Rotor Housing:
Center Iron:
Rear Rotor Housing:
Symptoms: NO power. I ran it above 7k in 2nd just to get up the hill to Nantahala Village, and was running in 3rd gear above 7k during the Friday Morning Fun Run. I did a quick and dirty compression check Thursday night at the cabin, and found the rear rotor was missing an apex seal. Puff-nothing-nothing-puff-nothing-nothing.
I've had some issues getting the flywheels off of the two motors I popped this year, so when I was in the garage today I hit both of them 3 or 4 times, and to my surprise the flywheel came off of the DGRR motor. Three irons, one rotor, and the e-shaft where salvageable. The rear rotor has some gnarly damage to it, including indentations, a mangled apex seal groove, and a piece of an apex seal embedded into the rotor face. The rear housing was gouged to hell, which I was expecting.
What I wasn't expecting was to find mass chrome flaking (110k motor out of an '85) and a BROKEN apex seal on the front rotor. Here are the pictures:
Front rotor broken Apex seal:
Front Rotor Housing:
Center Iron:
Rear Rotor Housing:
01-05-12, 08:18 PM
#7
I figured that I had driven all the way down there and the damage was already done, so I drove the car with two broken apex seals for a couple of days. IDK how they broke, but I was impressed with the carnage.
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01-05-12, 09:42 PM
#10
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Mine had similar flaking and apex seal damage, though not days of driving worth. I popped the seal a couple blocks from my place so I drove it home and parked it. That's some impressive damage.
01-05-12, 11:09 PM
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Probably what happened to mine. I was having detonation issues on the way down to DGRR09 because I was running the carb too lean trying to save gas. Finally tweaked it after the 800 mile drive and the car was happy, but it blew up that August. Don't recall how fresh the plugs were though.
01-06-12, 11:43 AM
#12
Probably what happened to mine. I was having detonation issues on the way down to DGRR09 because I was running the carb too lean trying to save gas. Finally tweaked it after the 800 mile drive and the car was happy, but it blew up that August. Don't recall how fresh the plugs were though.
01-06-12, 03:53 PM
#13
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looks like a normal 110k 12A to me! apex seals break in those, it just seems to happen. also notice the housings are peeling, so even if you tore it down BEFORE DG, the housings were bad...
01-08-12, 12:34 AM
#17
That is pretty bad. Did you happen to log the MPG on it? I had a blown 13b in my 87 parts car car Blown rear with 1 bad seal.Started and idles fine, but SLOW acceleration (topped out at 55MPH) and I went through 2 gallons of gas in 8 miles, lol. Surprised you were able to drive it very far.
01-08-12, 02:18 PM
#18
That is pretty bad. Did you happen to log the MPG on it? I had a blown 13b in my 87 parts car car Blown rear with 1 bad seal.Started and idles fine, but SLOW acceleration (topped out at 55MPH) and I went through 2 gallons of gas in 8 miles, lol. Surprised you were able to drive it very far.
4/27/2011: 10.508mpg
4/28/2011: 13.834mpg
4/28/2011: 13.378
4/28/2011: 15.929
4/28/2011: 17.038
4/28/2011: 14.023
4/29/2011: 10.914
4/29/2011: 10.355
It had a lumpy idle, started hard, and to get through the mountains I was spinning 7k+ the entire time. Probably the cause of the stuck side and corner seal. I could get up to 65 or 70mph, but it took FOREVER and I had to spin the hell out of the motor and keep it a gear or two lower than I normally would.
01-09-12, 12:12 AM
#19
I think mine was doing 7k in 3rd to hit 55MPH. I wonder if one were to unplug the blown rotor's injectors if it would run as a "proper" 1 rotor in a pinch. The blown seal in my rear rotor probably acted like a vacuum leak ad the computer tried to spray WOT fuel to the rear?
01-09-12, 08:39 PM
#20
I think mine was doing 7k in 3rd to hit 55MPH. I wonder if one were to unplug the blown rotor's injectors if it would run as a "proper" 1 rotor in a pinch. The blown seal in my rear rotor probably acted like a vacuum leak ad the computer tried to spray WOT fuel to the rear?
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