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289 Flywheel Installation

  • Thread starter Thread starter Blu-Steel
  • Start date Start date Oct 25, 2007
B

Blu-Steel

Member
Dec 29, 2006
92
0
7
Waynesville, MO
Oct 25, 2007
#1
  • Oct 25, 2007
  • #1
Does it matter how the flywheel is bolted to the crank in relation to the harmonic balancer? I ask because I know the balancer and flywheel are 28 oz imbalance, and I noticed the flywheel has an offset bulk in the casting, so that got me to thinking it might throw off the balance if I mount it wrong. It's an original flywheel that I had resurfaced and I am putting it on my newly rebuilt engine.
 

65fastbackresto

Active Member
Apr 13, 2007
1,229
7
39
AR
Oct 25, 2007
#2
  • Oct 25, 2007
  • #2
It`ll only go one way

The bolt pattern is directional so to speak, the holes will only line up in one position. Rotate the flywheel till all the holes show up.
 
B

Blu-Steel

Member
Dec 29, 2006
92
0
7
Waynesville, MO
Oct 26, 2007
#3
  • Oct 26, 2007
  • #3
Thanks. I didn't notice the bolt patern being different since I put it back on the way it was on the old engine I took it off of. I had a vibration in that engine and wondered if it might have been caused by the flywheel being incorrectly mounted. It looks like the old engine was remanufactured by one of those mass engine rebuilders since I have two #5 connecting rods, two #7 connecting rods and two #3 connecting rods. I bet they didn't balance the rotating assembly which caused my vibrations. I'm replacing it with a PAW engine which is balanced so I wanted to be sure I got the flywheel right. Thanks again.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Oct 26, 2007
#4
  • Oct 26, 2007
  • #4
Make sure you have the right imbalance weight flywheel. There are two weights for small blocks---28 oz & 50 oz.
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Oct 26, 2007
#5
  • Oct 26, 2007
  • #5
Blu-Steel said:
I bet they didn't balance the rotating assembly which caused my vibrations. I'm replacing it with a PAW engine which is balanced so I wanted to be sure I got the flywheel right.
Click to expand...

It's possible, but like D.H. said, make sure you have the right flywheel imbalance on the flywheel for the engine you have before getting a new one. I will say that so far my PAW engine is pretty nice. The crank and rods were rebuilt(and all the same numbers), but everything else was new, even the block.
 

BarnStang

Founding Member
Mar 2, 2001
1,260
3
39
Hagerstown, MD
Oct 27, 2007
#6
  • Oct 27, 2007
  • #6
You will need to know what imbalance the motor is that you bought. THen the harmonic balancer and the flywheel need to match that. You also need to know for sure what imbalance the flywheel and harmonic balancer are that you have. The flywheel will be easy, the cast weight will be small for 28oz early style, and large for 50oz latemodel style. Maybe someone has a couple pictures of each they could post up just in case. Size is a matter of perspective And I'm not sure how to tell on the harmonic balancer. I'll defer that to someone who knows for sure cause I don't want to guess.
You can also take your balancer and flywheel to a good machine shop and they can spin them and tell you what the imbalance is.
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Oct 27, 2007
#7
  • Oct 27, 2007
  • #7
If the flywheel and balancer are Ford parts, then the part number can also reveal what balance factor they have. A part number starting with C or D will rule out 50oz as a possibility because 50oz wasn't used until the early '80s. The counterweight mass can also be determined by looking at the back of the flywheel.

Scroll about halfway down on this:

http://www.fordmuscle.com/archives/2000/09/t5swap/index.php
 
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