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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Engine Fresh Rebuild Vibraton/shutter At High Rpm

  • Thread starter Thread starter jmil918
  • Start date Start date May 28, 2014

jmil918

New Member
Oct 16, 2012
24
0
2
May 28, 2014
#1
  • May 28, 2014
  • #1
I just completed my first rebuild on my 95 Mustang 5.0 everything went pretty smooth and the car started right up and idled great. However, when I push the RPMs up I get a very bad vibration. This happens in neutral as well as driving down the road so that should eliminate anything to do with the drive shaft. After doing some research I think I might have made a rookie mistake......

Almost all of the parts in the engine are new with the exception of the block, the crank, and the connecting rods. The mistake I believe I made was not having everything balanced together. Everything I purchased was balanced at 50oz, but I've been told that even if they are balanced the same, they still need to be balanced together by a machine shop.

One additional thing to note, I did NOT have the machine shop line hone the mains/crank (Another no no) and when I got it back from the machine shop the crank was pretty tight, but I used thinner bearings and everything checked out with plastigauge. Can anyone weigh in on if I'm on the right track or a possible solution? I have removed, cleaned, and reinstalled the harmonic balancer and there was no change. Thanks!
 

jmil918

New Member
Oct 16, 2012
24
0
2
May 29, 2014
#2
  • May 29, 2014
  • #2
Bump
 

toyman

10 Year Member
Jul 19, 2007
1,944
54
79
Vernon BC
May 29, 2014
#3
  • May 29, 2014
  • #3
Is the HB new and 50 oz and not 28 oz by mistake?
 

jmil918

New Member
Oct 16, 2012
24
0
2
May 29, 2014
#4
  • May 29, 2014
  • #4
The HB and the flywheel are both new & balanced from 50oz. They were ordered from reputable places (American Muscle & Summit), is there a way to distinguish between 28 & 50oz?
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,644
214
Acworth, GA
May 31, 2014
#5
  • May 31, 2014
  • #5
Ugh. Did you have the rods resized?

Kurt
 

jmil918

New Member
Oct 16, 2012
24
0
2
May 31, 2014
#6
  • May 31, 2014
  • #6
No, I was told since I was re-using the same rods, crank, mains, and bolts that I wouldn't have to do that. Was I told bad information?
 

toyman

10 Year Member
Jul 19, 2007
1,944
54
79
Vernon BC
May 31, 2014
#7
  • May 31, 2014
  • #7
I don't think there is anything that can visually distinguish them. They must also match the flywheel imbalance as well. I would call the source provider and ask if they can confirm the part number for you. All the 302s from the early 80s forward are 50 oz imbalance engines.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,644
214
Acworth, GA
May 31, 2014
#8
  • May 31, 2014
  • #8
Generally whenever you have the bearings changed you do a line hone and a rod resize. I would consult another machinest to see if the first one missed something. It could be something serious or something simple. I have seen engine vibrations that were fixed by swapping around the 6 bolts on the pressure plate.

Kurt
 

Jeff Massey

New Member
Jun 20, 2016
14
0
1
Centerville, OH
Jun 22, 2016
#9
  • Jun 22, 2016
  • #9
Did you ever figure this out? I DID have everything balanced and have the exact same problem you describe with my 66 (with 68 302)
 
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