3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

What are the signs of a blown motor?

Thread Tools
 
Search this Thread
 
Old Aug 31, 2004 | 04:41 PM
  #1  
Rx-7pl's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Nov 2003
Posts: 275
Likes: 0
From: Chicago
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
Reply
Old Aug 31, 2004 | 06:28 PM
  #2  
gotorx7's Avatar
The 7 can't lose!
Tenured Member 15 Years
 
Joined: Feb 2002
Posts: 487
Likes: 1
From: Adelaide, South Australia
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...
Reply
Old Aug 31, 2004 | 07:07 PM
  #3  
rotoryspeeddreamz's Avatar
Full Member
Tenured Member 05 Years
 
Joined: Nov 2002
Posts: 184
Likes: 0
From: Bay Area
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.
Reply
Old Sep 1, 2004 | 12:31 AM
  #4  
GoodfellaFD3S's Avatar
Original Gangster/Rotary!
Veteran: Army
Tenured Member: 25 Years
Liked
Loved
iTrader: (213)
 
Joined: Mar 2001
Posts: 30,782
Likes: 641
From: FL-->NJ/NYC again!
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.
Reply
Old Sep 1, 2004 | 12:34 AM
  #5  
RX794's Avatar
NYC's Loudest FD
Tenured Member 20 Years
 
Joined: Mar 2001
Posts: 1,539
Likes: 1
From: Long Island, NY
I'll add to this:

Hard to start
Lower than normal vaccum on the boost guage at idle.
Reply
Old Sep 1, 2004 | 12:52 AM
  #6  
FD from R1's Avatar
Banned. I got OWNED!!!
 
Joined: Jul 2004
Posts: 88
Likes: 0
From: DET
this should be a sticky

it re-appears weekly
Reply
Old Sep 1, 2004 | 01:32 AM
  #7  
saburo's Avatar
No More 7
Tenured Member 05 Years
iTrader: (1)
 
Joined: Apr 2004
Posts: 723
Likes: 0
From: San Diego, CA
This is a shot in the dark, but if the engine blows, you'll know because it won't run. hahaha. im cool.
Reply
Old Sep 1, 2004 | 02:18 AM
  #8  
HKS SpiritR's Avatar
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2004
Posts: 8
Likes: 0
From: Indonesia
hard to start or wont even start at all
Reply
Old Sep 1, 2004 | 02:27 AM
  #9  
fnrxtreme's Avatar
sone
 
Joined: Aug 2004
Posts: 1
Likes: 0
From: apple valley minnesota
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
Reply
Old Sep 1, 2004 | 07:53 AM
  #10  
cabaynes's Avatar
Old and grumpy
Tenured Member: 20 Years
iTrader: (4)
 
Joined: Mar 2002
Posts: 2,600
Likes: 6
From: San Francisco, CA
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
Reply
Old Sep 1, 2004 | 08:26 AM
  #11  
DaleClark's Avatar
RX-7 Bad Ass
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (56)
 
Joined: Jan 2002
Posts: 15,622
Likes: 2,723
From: Pensacola, FL
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
Reply
Old Sep 1, 2004 | 01:22 PM
  #12  
Houdini's Avatar
Senior Member
Tenured Member 15 Years
iTrader: (3)
 
Joined: Aug 2002
Posts: 435
Likes: 0
From: Bay Area, CA
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.
Reply
Old Sep 1, 2004 | 01:45 PM
  #13  
Rx-7pl's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: Nov 2003
Posts: 275
Likes: 0
From: Chicago
My motor is in perfect condition I just asked a question because i got a friend who might have blown engine
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
whinin
Introduce yourself
17
Mar 30, 2019 07:53 PM




All times are GMT -5. The time now is 10:02 PM.