21 replies to this topic

[nicklouse]

Never really looked at them much but recently I have seen more than my fair share of them.

Including these new replacement ones.

Disregarding the undamped early A version and the cooper S two part one

How many BL/BMC/Leyland etc ones were made?

I had thought 2 but I have found a third.

Pics tomorrow.

[Spider]

3 that come to mind, though, there would be a 4th, but for all intensive purposes is the same as one of the 3 mentioned. The difference being it had an added sheet metal piece for an LED pick up (which I know little of), that only seems to crack around it's rivets so it can rattle.

 

If you're looking for a New replacement, those current sold by Mini Spares come apart (I think they may have been withdrawn in fact). The only one I'd recommend is a Romac, though I also believe the KAD ones are good.

 

http://www.romac.com.au/balancers.html

[nicklouse]

Ok I an disregarding any shielding or extra metal.

I did not notice it when first looking.

[Spider]

There's the more common single groove, a twin groove that the same width and another that's a little narrower than the first.

[nicklouse]

The three damper.



It is the one in the middle that is new to me.

25mm total thickness as opposed to 30mm

[Orange-Phantom]

The Kad damper is a viscous type hence the cost. I don't know anyone one else who makes one for the A series.
The viscous type of crank damper is able to damp harmonic frequencies right across the Rev range and not just at one specific frequency which the elastomer types do. If you tune your engine then you can shift the harmonic frequencies the engine generates and thus your stock damper can be ineffective at damping the dominant harmonic frequency to which it is tuned to.
Many people fit old worn dampers back on their engine which can store up serious trouble for later.
Unless someone else out there makes a viscous damper for the A series then the Kad damper is the ultimate, just bleeding expensive! Plus you'll have to modify the engine steady if you want to be able to change the fan belt without pretty much taking the engine out.

[nicklouse]

Thanks but has diddly squat to do with the topic.

[Spider]

I've not seen (from your first photo) the top or middle ones, so that's 2 new ones for me.

 

In particular on those what's grabbed my eye as being different and import here is the amount (and therefore mass of) material that's mounted to the rubber, they are tuned differently and presumably for different engines. This to me, warrants some further looking in to.

 

The total widths I've seen before, for us here, the thicker types are more common, though we did get some quite late ones (late for us - 1980 / 1981) that did have the thinner types fitted.

 

I'm a bit tied up for this next week, none the less, I'll try and compile a list of all the factory dampers and then we can try to work out what was fitted to what - then it's a case of trying to find out what they look like!

Edited by Moke Spider, 30 October 2016 - 07:05 PM.

[nicklouse]

To me the top is the standard A+ and the bottom on the standard A 1275

The middle one is definitely A+ with the dirt shield which was lose so now removed.

What is interesting no balance drilling.

[Orange-Phantom]

Cheers!

Moke mentioned the Kad type and I thought the info may be HELPFUL and shed a bit of info on it, just in case you or someone else reading this topic were thinking of getting a new damper. Instead of bunging any old, potentially knackered damper back on their car.

[Spider]

I wouldn't read too much in to it not having any material removed for a balance. If you think something's off here, you could check it on a static balance, not conclusive but maybe helpful.

 

I have seen them at that thickness (I might even have a couple in the draw), jut not with that much mounted material.

[Northernpower]

To me the top is the standard A+ and the bottom on the standard A 1275

The middle one is definitely A+ with the dirt shield which was lose so now removed.

What is interesting no balance drilling.

If the middle one has a different or no timing mark I think it may be from a Morris Marina. From memory the timing Mark was on a separate plate riveted on to the pulley.

[nicklouse]

To me the top is the standard A+ and the bottom on the standard A 1275
The middle one is definitely A+ with the dirt shield which was lose so now removed.
What is interesting no balance drilling.

If the middle one has a different or no timing mark I think it may be from a Morris Marina. From memory the timing Mark was on a separate plate riveted on to the pulley.

Good point well made. It does, but I have not looked at the relative positions.

[Compdoc]

Thanks but has diddly squat to do with the topic.

I thought Orange-Pantom's input was very relevant to the topic. All the time I was reading I was wondering why there was so many different crank dampers produced. Now I know.

So when we have all the dampers lined up and labelled we still don't have information on the RPM band that each work at, so no idea which one to use on each particular state of tune. As David Vizard says, (so it must be true), "Lightening the flywheel, or any reciprocating part, can move the resonant frequency of a vibration up the rev range".

So the only answer, if you are continually upgrading your engine, is to weigh your collection of dampers in for scrap value and blow £250 on a KAD one. It's cheaper in the long run.

[nicklouse]

so again someone who did not read the post.

 

How many BL/BMC/Leyland etc ones were made?

 

 

there are many after market ones out there and that has diddly squat to do with my question.

 

yes KAD do theirs MED also do one and I can think of a few other but since when did they make OE parts Never and this is what I am trying to identify.