What are the signs of a blown motor? - RX7Club.com

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What are the signs of a blown motor?

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Old 08-31-04, 04:41 PM   #1
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What are the signs of a blown motor?

I want to know what are the signs of a blown motor?And if the motor is blown can you still drive it?
I need as much info as possible.
thanks
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Old 08-31-04, 06:28 PM   #2
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Depending on what has actually blown you could have :

Rough Idle
Miss at Low Revs
Loss of Power
Excessive Smoke
Strange noises

Whatever, the more you drive it, the more chance you have of doing further damage and costing yourself more on a rebuild.

Flat-bed it to someone who can do a proper compression check..

Good luck...
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Old 08-31-04, 07:07 PM   #3
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Quote:
Originally Posted by gotorx7
Flat-bed it to someone who can do a proper compression check..
Yep, that's definately the best way to tell for sure.
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Old 09-01-04, 12:31 AM   #4
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Your motor will shake like crazy at idle. You will have low vacuum on your boost gauge and the needle will bounce around while the idle rpm is still constant.

If it is blown, don't drive it.
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Old 09-01-04, 12:34 AM   #5
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I'll add to this:

Hard to start
Lower than normal vaccum on the boost guage at idle.
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Old 09-01-04, 12:52 AM   #6
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this should be a sticky

it re-appears weekly
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Old 09-01-04, 01:32 AM   #7
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This is a shot in the dark, but if the engine blows, you'll know because it won't run. hahaha. im cool.
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Old 09-01-04, 02:18 AM   #8
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hard to start or wont even start at all
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Old 09-01-04, 02:27 AM   #9
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I had one blow on me last year and it did start but it took awhile then when it starts it smokes like crazy, almost like you are not sure if it is comletely missing, firing wrong shaking but will still drive im not sure if this will help but that is what happened to me after i blow out one seal and cracked a housing
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Old 09-01-04, 07:53 AM   #10
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ROTORS WILL COME FLYING OUT OF THE ENGINE AND PUT HOLES IN YOUR HOOD! OHH NOES!!!!

haha, just playin... get it compression checked. it's the quickest way to tell. otherwise it could be something stupid like your MAP sensor
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Old 09-01-04, 08:26 AM   #11
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You can drive a car with a blown motor - depends on how blown it is. I drove my old TII with a blown motor for some time - of course, the motor was relatively fresh, so what compression it did have was good.

Really, once it's blown, the damage is done. It's not gonna get any worse. If you broke an apex seal, the rotor and housing are damaged/unuseable, and they're not gonna get any better.

If it's a coolant seal problem, I'd definitely pull and tear down the motor soon. The faster you can get the motor apart, the better - coolant and water will pool in the engine and rust the seals into the rotor, making the ENTIRE motor useless - as in, no salvageable parts. Get it apart, cleaned up, oiled, and stored.

Dale
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Old 09-01-04, 01:22 PM   #12
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Quote:
Originally Posted by dcfc3s
Really, once it's blown, the damage is done. It's not gonna get any worse. If you broke an apex seal, the rotor and housing are damaged/unuseable, and they're not gonna get any better.

Dale
I would say don't, loose pieces in the engine can still do damage. Especially if you're planning on reusing the sides. Also, the turbos probably won't like the taste of apex seals since thats where the seals end up when they get ejected from the motor.

Do the right thing, test the compression.
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Old 09-01-04, 01:45 PM   #13
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My motor is in perfect condition I just asked a question because i got a friend who might have blown engine
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