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Is my engine toast, broken harmonic balancer

  • Thread starter Thread starter jstang209
  • Start date Start date Oct 11, 2010
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
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Stockton 209
Oct 11, 2010
#1
  • Oct 11, 2010
  • #1
So I was driving down the street and bam the got worse sound out of an engine you can possbily hear.. shut the car right off and tow it home.. and find this, as you can see there is a large crack on the shaft that slips onto the crankshaft, so I remove the balancer and notice that I can slightly pull out/push in the part of crankshaft that sticks out, this isnt a good sign right, did my crankshaft or something in there possbily break too?

 
L

Lawbreaker5.0

Member
Feb 20, 2009
543
2
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Texas
Oct 11, 2010
#2
  • Oct 11, 2010
  • #2
Picture doesn't work. But sounds like your thrust bearing is shot if you have that much endplay on the crankshaft.
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,016
1,613
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NJ
Oct 11, 2010
#3
  • Oct 11, 2010
  • #3
Picture didn't open for me, but i can tell you this, anytime a 5.0 has a balancer failure, theres a good chance the engine isn't far behind. Depending on the damage you may be able to put a new balancer on, but IMO you engine isn't going to last long.

If i were you, i'd be preparing to buy an explorer engine and swap it out with yours.
You can use car-parts.com to find them local to you.

This is why i tell people the balancer should fall under the category of routine maintainence, not fix it when it breaks.
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Oct 11, 2010
#4
  • Oct 11, 2010
  • #4
thing was a brand new motor straight from ford..i think the 3 yr warranty just expired too..fml..pic should work now
 
L

Lawbreaker5.0

Member
Feb 20, 2009
543
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Oct 11, 2010
#5
  • Oct 11, 2010
  • #5
If it just expired, I know certain places will make an exception, but 6months+ over and your screwed.

You should check your oil or cut your oil filter to check for bearing material. And also check the exact endplay with a dial indicator.
 
L

Lawbreaker5.0

Member
Feb 20, 2009
543
2
18
Texas
Oct 11, 2010
#6
  • Oct 11, 2010
  • #6
The actual crank pulls in and out or he harmonic balancer. You should be able to pull the balancer off without the removal tool after you pull the bolt.
 

Dino Dino Bambino

15 Year Member
Jun 13, 2007
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Oct 12, 2010
#7
  • Oct 12, 2010
  • #7
It sounds like the balancer might have broken the front of the crankshaft in which case, just pray that it didn't take out the front of the block as well.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Oct 12, 2010
#8
  • Oct 12, 2010
  • #8
It is weird to crack the hub of the balancer with out another type of failure.....pull the balancer off and see if you can move the crank, if it moves more then .008" total the thrust is gone and the motor needs to come apart.....
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
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108
Chicagoland
Oct 12, 2010
#9
  • Oct 12, 2010
  • #9
Bullitt95 said:
It sounds like the balancer might have broken the front of the crankshaft in which case, just pray that it didn't take out the front of the block as well.
Click to expand...

I agree. Try rotating the engine over by hand and see what you find.
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Oct 17, 2010
#10
  • Oct 17, 2010
  • #10
finally had sum time to pull the motor and bam..yay for me...



So what's next...can I just buy another crank shaft and put it back in? It only slightly hit the bottoms of the pistons and left a couple of scratches..I dont need to replace them do I?
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,016
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NJ
Oct 17, 2010
#11
  • Oct 17, 2010
  • #11
Sorry, i know the feeling, that's why when you said balancer, i figured she was gone.

No don't buy another crank or even attempt to repair it if it's a stock shortblock.
Get an explorer engine and swap out the cam and accessories.
Use car-parts.com to find a price and local engines, i looked a while back for my brother and there was literally hundreds of them on there.
 

Dino Dino Bambino

15 Year Member
Jun 13, 2007
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Cyprus
Oct 17, 2010
#12
  • Oct 17, 2010
  • #12
jstang209 said:
finally had sum time to pull the motor and bam..yay for me...



So what's next...can I just buy another crank shaft and put it back in? It only slightly hit the bottoms of the pistons and left a couple of scratches..I dont need to replace them do I?
Click to expand...

Looks like I was right. I was hoping otherwise. If the block is still good, you might as well buy a 331 or 347 stroker kit (you need a new crank anyway and possibly pistons too) and gain something from your misfortune.
 
L

livinitup11

New Member
Oct 17, 2010
1
0
0
New Jersey
Oct 17, 2010
#13
  • Oct 17, 2010
  • #13
This brings back memories for me my 306 did the same thing. My Block cracked and the front half of the crank and balancer were hanging there. Just a thought but might want to invest in a block anyway. Would suck to rebuild the Engine and find out later you had a hairline crack. I went with the 347 and a sportsman block. was a blessing in disguise for me
 

Cobra912

Active Member
May 1, 2005
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Wish I was anywhere but here
Oct 17, 2010
#14
  • Oct 17, 2010
  • #14
yikes sorry to see
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Oct 17, 2010
#15
  • Oct 17, 2010
  • #15
This gives me a perfect reason to start my 351 swap but I was recently laid off and UI is a joke..so I dont really have the money right now for anything special. The block is still in good shape, so I would really like to take the cheapest route available just so I can get her running again. She is my DD
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,016
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NJ
Oct 17, 2010
#16
  • Oct 17, 2010
  • #16
jstang209 said:
This gives me a perfect reason to start my 351 swap but I was recently laid off and UI is a joke..so I dont really have the money right now for anything special. The block is still in good shape, so I would really like to take the cheapest route available just so I can get her running again. She is my DD
Click to expand...

Cheapest route is another complete engine.
I've been in your position, no matter how you slice it, a rebuild is going to cost more than either a 5.0 donor from another mustang or an explorer engine.
You can't just slap the parts back in there, unless of course you don't mind putting oil in the car every few days.
 

LarsD

Founding Member
Jul 2, 2002
2,680
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123
Texas
Oct 17, 2010
#17
  • Oct 17, 2010
  • #17
Ouch, that thing is going to need a complete rebuild. Block might even have some hairline cracks that you can't see that could cause problems later on.

Funny, my old 89 cracked its balancer at some point in its life and other then a minor vibration I never new it was busted till I took it apart. I would take it to the track and hot lap it like crazy and it never gave me trouble once. :-/
 
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