View Full Version : Damper to be rebuilt?

02-08-2008, 10:59 AM
This is my damper. Machine shop recommends rebuild.


Thought I read a thread that said the new replacement
parts do not have the timing marks, making rebuild
more attractive. Haven't compared prices.

Curious. What's involved in rebuild? Looks, at first,
like a new rubber. Does this rubber push in a groove?
Is it one piece front to back? What do you think about
its condition from the photos?




and hardly know why...but, then, why not this shot --


Oh, actually, this last shot because I was curious
as to the timing marks. Looks like somebody scratched
in their own mark or something....no?

Whatdoyathink Forum?

02-08-2008, 11:01 AM
Kinda think I need to increase the photo size in
Photobucket. Sorry if they ain't so hot, but I'll
try a larger size next time.

02-08-2008, 11:06 AM
What size do you have your camera set to?

02-08-2008, 11:23 AM
You can selected multiple photos in Photobucket, then at the bottom of the screen select ,Generate HTML and IMG code,. On the next page, click on the 'IMG clickable thumbnails for message boards - recommended' and paste into your response.

Thumbnails load fast and provide the reader an option to view in the original size.

02-08-2008, 11:41 AM
Send your damper to Damper Dudes. They are up in Anderson
They are fast and it returns looking like new. About $90.00 to $120.00

Damper Dudes
6180 Parallel Rd
Anderson, CA 96007

02-08-2008, 01:05 PM
Tinster stupid question No.793-795

Why is that thing called a damper?
Why do they have to be rebuilt?
How can I tell if mine is bad?

Mine has no numbers on it. I have one etched
line clear across and one line halfway across.

Thanks as always,


02-08-2008, 03:52 PM
793 - Its called a damper because it is supposed to damp the torsional resonance in the crankshaft by setting up a cancelling resonance. There is the potential for a veeeeery long bit of explanation here. But the Cliff Notes are: the central part is clamped to the shaft to be dampened. The outer is suspended from the inner by a rubber ring. The outer moves on a (brief) time delay from rotational energy from the inner. So the power spikes from the pistons are sent to the outer via the delaying rubber, when the rubber begins to snap back the energy it carries is supposed to counteract the tendancy of the shaft to "wind-up" along its length from the aforementioned power spikes. Torsional Resonance is a difficult bit of physics to grasp. The damper cancels it (mostly).

794 - The rubber begins to get all crinkly and the ability to absorb the pulses diminishes/evaporates. If the outer comes off... Your crankshaft will crystalize (in a strange fashion) and fail. Certinally cheaper to rebuild/replace the damper.

795 - Is the aforementioned rubber crunchy? Can you break pieces off with your fingers? With a screwdriver? If so you should look into a professional opinion, and potential rebuild. Judging from the photos above, that damper needs rebuilt.

I'll expound with scientific frappus to drangle your mind at length if requested. The numbers are, in fact, kinda interesting...

If you are a total geekmier like me.

02-08-2008, 05:01 PM
Forego the dissertation, Jer. You're right. The damper pictured is approaching end-of-life. The cracks around the front diameter are a good enough indicator. The rubber has lost compliance. When that happens, the "damper" becomes an "amplifier" instead.

Dennis, turn yer head an' cough. Then package that thing up and send it to the guys in Anderson. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

02-08-2008, 05:09 PM
Thanks, amcboy. Your brief version is quite adequate
to satisfy me. I'm a get to the bottom line kind of
guy. But again, thanks for being willing -- and, of
course, for your input, more to the extent that I can

02-08-2008, 06:27 PM
Well if I can obfuscate the conundrum with blatherings of co-incidence just let me know!

Er sumthin'...

In Bad Taste:
Doctor: Turn your head and cough...
Patient: I will when you put me down!

02-09-2008, 05:53 AM
amcboy thanks!!

Your explanation greatly appreciated.

I'll have to check mine since it is some oddball unit
DPO Pedro had installed from a junkyard car salvage.


02-09-2008, 08:19 AM
Methinks that pulley looks like 99.4% of all pulleys on all TR6s left in the world.

02-09-2008, 08:22 AM
And I am sure that the dudes at Damper Dudes know what they are doing (I have heard of them before) but what are the chances that they will be able to line up your timing marks with the key hole in the crank perfectly? And if they are off a degree or two, what a mess.

02-09-2008, 09:34 AM
They have th' spec's. Besides, you really think the 'factory' ones are all that accurate?!?! /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif

02-09-2008, 10:16 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]They have th' spec's. Besides, you really think the 'factory' ones are all that accurate? /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif [/QUOTE]

Only the ones done before the rugby match.

02-09-2008, 10:41 AM
If you have your cylinder head off and can get a dial indicator, you can quickly check your timing mark!

Run cylinder 1 to near TDC and put dial indicator on top of piston.

Go to the highest indicated position, and your timing mark should be at zero.

Some (with more patience and better tools than I) have done this through the plug hole.

IF you do re-mark your damper, be sure to stamp Xs through the old line!

Someday you'll be the DPO...

02-09-2008, 10:49 AM
Those of us lucky enuff to have TWO bump-sticks can go straight down thru th' plug'ole with an indicator probe...
but gettin' that magnet to stick to aluminium is a challenge. /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif

It's always a good idea to check absolute TDC against those damper "suggested TDC" marks, in any case.

02-09-2008, 11:24 AM
FWIW... I had my damper rebuilt by the damper dudes about eight years ago. When I rebuilt the engine I checked TDC #1 to the timing marks on the pulley/damper. They were dead on. The damper dudes are the dudes. Or were at least for me. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

02-09-2008, 11:34 AM
If you look at what they do, it appears that they know their stuff. I don't think that they'd last to long in the Ford/Chevy HP forums if they didn't get the marks dead on for some guys 427 engine.