Notices
Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by: KPower

what broke in my motor?

Thread Tools
 
Search this Thread
 
Old Jun 5, 2010 | 10:49 AM
  #1  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default what broke in my motor?

https://www.miataturbo.net/showthrea...gt3076r&page=2

I bought this last fall
it definately wasn't drop in and go... there were no gaskets installed anywhere in the motor.
I took it all apart, took out everything but the oil pump, rods and pistons
and managed to get it running in the car this spring.


in the middle of a run i hear hesitation and pull over...


now there is a knocking noise in the motor....towed the car home.


any ideas on where to start looking?? its still running on all 4 cylinders and everything sounds normal while cranking it over. i only hear the knocking once it fires...

ideas?

i was logging while this happened and everything looks good in the log.
also have a very conservative spark map (according to rafa, car wouldn't even be on the road without him)

thanks!
Old Jun 5, 2010 | 11:08 AM
  #2  
kotomile's Avatar
Elite Member
iTrader: (24)
 
Joined: Oct 2006
Posts: 7,537
Total Cats: 42
From: Monterey, CA
Default

Your car has a motor? Most of ours have engines, I think you may be out of luck.
Old Jun 5, 2010 | 11:30 AM
  #3  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

Try using the "shift" key and making a few paragraphs and I'll consider providing information. Emphasis on "consider".
Old Jun 5, 2010 | 11:38 AM
  #4  
flier129's Avatar
Elite Member
iTrader: (7)
 
Joined: Jan 2008
Posts: 2,750
Total Cats: 320
From: Statesville, NC
Default

Bearings, little and big ends.
Check wrist-pins and wrist pin wires... to see if they're present.


My money is on bearings though.
Old Jun 5, 2010 | 12:02 PM
  #5  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

just checked compression
170-140-90-150

i'm on a crappy laptop in the drivers seat with a tiny shift key and i always mess my typing up when i use it, that and the finger i use is busy stretching out your sister... my apologies hustler, i do what i can.
Old Jun 5, 2010 | 12:06 PM
  #6  
dustinb's Avatar
Elite Member
 
Joined: Feb 2008
Posts: 2,321
Total Cats: 14
From: Victoria, BC
Default

Your motors is the funked.
Old Jun 5, 2010 | 12:09 PM
  #7  
flier129's Avatar
Elite Member
iTrader: (7)
 
Joined: Jan 2008
Posts: 2,750
Total Cats: 320
From: Statesville, NC
Default

Rings seated wrong or warped head or many other things.

I feel your pain.
Old Jun 5, 2010 | 12:10 PM
  #8  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

ok....what are the chances of the $$$$$$ rods/pistons being good????
Old Jun 5, 2010 | 01:05 PM
  #9  
Rafa's Avatar
Elite Member
iTrader: (22)
 
Joined: Dec 2006
Posts: 3,224
Total Cats: 3
From: Sunny Spanish speaking Non US Caribbean
Default

Originally Posted by Preluding
just checked compression
170-140-90-150

i'm on a crappy laptop in the drivers seat with a tiny shift key and i always mess my typing up when i use it, that and the finger i use is busy stretching out your sister... my apologies hustler, i do what i can.
Compression numbers on cylinder #3 don't look good at all Alex. I have to say I'm a little surprised about the numbers on #2 and #4 too. Your engine hadn't been running for long.

I think you're assessment of a bearing failure will turn out to be right. I'm curious to know about your pistons and rods.

Please keep me posted.

Let me know how I can help you.
Old Jun 5, 2010 | 01:18 PM
  #10  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

I guess i know what i'm doing this weekend.

the compression numbers really surprised me too! looks like the whole thing is coming apart and at the very least being reassembled. I'm glad my spare engine didn't end up selling now.

live and learn...for anyone reading this...don't buy a motor assembled by someone else unless you know for sure its professional and warrantied.
Old Jun 5, 2010 | 01:20 PM
  #11  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

this motor lasted 600miles.

200 of them boosted.... the funnest 200miles i've ever had in a miata

just WOW
Old Jun 5, 2010 | 03:42 PM
  #12  
Rafa's Avatar
Elite Member
iTrader: (22)
 
Joined: Dec 2006
Posts: 3,224
Total Cats: 3
From: Sunny Spanish speaking Non US Caribbean
Default

Originally Posted by Preluding
this motor lasted 600miles.

200 of them boosted.... the funnest 200miles i've ever had in a miata

just WOW
That's the right attitude.

About the WOW: in Spain we have a saying: "que me quiten lo bailao". It translates to something like: no one can take away the fun I've already had!
Old Jun 5, 2010 | 04:25 PM
  #13  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

Thats the fun thats encouraging me to keep working on it and get it back on the road again.


No regrets....well....maybe I shouldn't have drank so much last night
Old Jun 5, 2010 | 05:47 PM
  #14  
flier129's Avatar
Elite Member
iTrader: (7)
 
Joined: Jan 2008
Posts: 2,750
Total Cats: 320
From: Statesville, NC
Default

Originally Posted by Preluding

live and learn...for anyone reading this...don't buy a motor assembled by someone else unless you know for sure its professional and warrantied.

I could of told you that one from personal experience as well

Mine lasted 600 miles of boost, it was great
Old Jun 5, 2010 | 07:34 PM
  #15  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

Originally Posted by flier129
I could of told you that one from personal experience as well

Mine lasted 600 miles of boost, it was great
I'm so sorry! but I'm glad i'm not alone, want to start a club?
Old Jun 5, 2010 | 08:01 PM
  #16  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

post your spark and fuel table. Then check the head and headgasket. I bet the motor is fine and something simple is fucked.
Old Jun 6, 2010 | 11:54 AM
  #17  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

Originally Posted by hustler
post your spark and fuel table. Then check the head and headgasket. I bet the motor is fine and something simple is fucked.
Ignition:

Name:  Ignition.jpg
Views: 118
Size:  253.2 KB

Fuel:

Name:  Fuel.jpg
Views: 97
Size:  257.9 KB

here ya go, Hope you're right!!!
Old Jun 6, 2010 | 12:13 PM
  #18  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

those tables look fine.
Old Jun 6, 2010 | 01:41 PM
  #19  
Preluding's Avatar
Thread Starter
Senior Member
iTrader: (10)
 
Joined: Aug 2007
Posts: 1,186
Total Cats: 4
From: Fredericton, NB
Default

thanks.... well.... unfortunately the midget in my engine with the hammer thinks otherwise
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
StratoBlue1109
Miata parts for sale/trade
21
Sep 30, 2018 01:09 PM
Joe Perez
Current Events, News, Politics
8
Sep 30, 2015 04:41 PM
viriiguy
General Miata Chat
5
Sep 28, 2015 07:39 PM
Squiblez
Build Threads
2
Sep 22, 2015 10:17 AM
aidandj
WTB
0
Sep 13, 2015 05:12 PM




All times are GMT -4. The time now is 04:13 AM.