425 harmonic balancer
Thread Starter
Registered User
Joined: Jun 2012
Posts: 121
From: Germany
425 harmonic balancer
As I am visiting the machine shop tomorrow.... does anyone have an exact dimension of the harmonic balancer's diameter where the front oil seal rides on? It' a '66 425 V8 out of my Toronado. I had to buy an aftermarket balancer 'cause mine fell apart... I have to work a little on the counterweight to make it fit..and I realized the outer diameter is 51,38mm and the oil seal sits a little too tight for my personal taste.. data from the national oil seal say it is for a 2" shaft and that's only 50,8mm. So before I modify mine I like to confirm with another original balancer...to be on the safe side. My original one is not for measuring.. the surface is shot... I modified it for a different oil seal and had to realize that I cannot find a company in Germany to overhaul the rubber part.
Thx a lot... and a happy new year for all of you
Thx a lot... and a happy new year for all of you
Registered User
Joined: Dec 2011
Posts: 7,286
I don't think you have a problem.
51,3 - 50,8 = 0,5mm or 0.020", which is not a bad interference for a rubber lip seal of 2.000" OD.
I could measure a stock balancer if you need, but if it's nominal 2" then it will measure 1.995 to 2.005 or so.
51,3 - 50,8 = 0,5mm or 0.020", which is not a bad interference for a rubber lip seal of 2.000" OD.
I could measure a stock balancer if you need, but if it's nominal 2" then it will measure 1.995 to 2.005 or so.
Last edited by Octania; Jan 1, 2014 at 10:41 AM.
Thread Starter
Registered User
Joined: Jun 2012
Posts: 121
From: Germany
Just for my own peace of mind... pls check a stock balancer... I am curious..
thx a lot
Harald
P.S.: I attached some details of the national seal. They are not very specific about the details except that it is a 2" shaft. Believe me 0.5mm is huge if it is to much for the seal. It will eat up of it sits too tight..
thx a lot
Harald
P.S.: I attached some details of the national seal. They are not very specific about the details except that it is a 2" shaft. Believe me 0.5mm is huge if it is to much for the seal. It will eat up of it sits too tight..
Registered User
Joined: Dec 2011
Posts: 7,286
Just for my own peace of mind... pls check a stock balancer... I am curious..
thx a lot
Harald
P.S.: I attached some details of the national seal. They are not very specific about the details except that it is a 2" shaft. Believe me 0.5mm is huge if it is to much for the seal. It will eat up of it sits too tight..
thx a lot
Harald
P.S.: I attached some details of the national seal. They are not very specific about the details except that it is a 2" shaft. Believe me 0.5mm is huge if it is to much for the seal. It will eat up of it sits too tight..
But, believe me, 0,5mm is not huge for a rubber seal
it's 0.020", on the diameter, so the seal rubber is displaced a mere 0.010" or 0,25mm - quite negligible...
Registered User
Joined: Dec 2011
Posts: 7,286
4 samples of used balancer, measured not of the wear groove, were:
50,74
50,76
50,78
50,76 mm
About 0,02-0,04 under nominal 50,8 or
0.0008" to 0.0024" under nominal 2.0000"
One was over 50,8 but it was not smooth shiny steel anymore, so that doesn't count.
PS there is a commonly used seal surface repair sleeve, which presses over this surface. I am pretty sure it is well over 0,25mm thick, and does not require a different seal.
So, we are back to... you don't have a fitment problem.
50,74
50,76
50,78
50,76 mm
About 0,02-0,04 under nominal 50,8 or
0.0008" to 0.0024" under nominal 2.0000"
One was over 50,8 but it was not smooth shiny steel anymore, so that doesn't count.
PS there is a commonly used seal surface repair sleeve, which presses over this surface. I am pretty sure it is well over 0,25mm thick, and does not require a different seal.
So, we are back to... you don't have a fitment problem.
Last edited by Octania; Jan 1, 2014 at 12:59 PM.
Thread
Thread Starter
Forum
Replies
Last Post
ForestMist66
Big Blocks
15
Oct 15, 2012 03:22 AM
