Chevrolet: aftermarket or custom rebuild?

Time changes everything.
Automobiles are in a time of great change.
Electric cars and autonomous automobiles are swiftly taking over as daily transport.
Petrol automobiles are becoming collectors items. Spare parts which are now cheap and easy to get are becoming rare and hard to come by.
We have stores of all kinds of rare and hard to find harmonic dampers and hubs and inertia rings.
We will be helping petrol powered auto owners to keep their precious collectible lovely cars on the road.
Naturally, our services to rebuild your old harmonic damper will cost more than a junky aftermarket part that won't last long and hasn't got a warranty.
We offer you a remanufactured OEM part for your old Chevrolet, Ford or Holden and it has a 5 year unlimited km warranty.
Our fee is NOT Competitive with Mexican parts, or Chinese parts.
Not Now.
But it sure as heck will keep your lovely old automobile on the road, purring like a happy cat.
And when the market for aftermarket cheap parts has meant those manufacturers have moved on to make other things and there are zero parts available from them, chances are, we will be here still refurbishing harmonic dampers, for what it costs us in time and materials to repair them.

Lincoln Continental 1966

In automotive history it's often said, if there were two cars made, then one of them will be in New Zealand somewhere. 

Today we feature our first video attempt to make a record of a damper we are rebuilding: a beautiful Lincoln Continental from 1966.

And on YouTube we find an original commercial from 1966 of the latest Lincoln Continental and all the latest fab up-to-date features.

Our aim in the future on our YouTube channel is to share with you a few of the secrets, joys and heartaches of rebuilding and remanufacturing harmonic dampers and crank pulleys from the many and varied parts that cross our work bench. 

Currently on the rebuild shelf we have a 1917 Studebaker harmonic damper. We aim to show you how we work on a rare and precious part like this to bring it back from the dead, to make it into a functioning part which the owner can fit with confidence to his vehicle.

I'll get a second-hand pulley, she'll be right mate!

So your crank pulley is broke and you are shopping around for another one and the wrecker has a second hand one from the same make and model of car.
If your car is 10 years of age or older, there's a good chance that the pulley is as close to munted as the one you just took off the crank shaft.

Why?

Because RUBBER is why.
Rubber is the part that most often fails in a crank pulley, crank balancer or harmonic damper.
Rubber is an organic substance that breaks down with heat, water, oil, use and simple age.
All rubber parts of your automobile are going to die a slow sad death at some stage and require replacement.

When the rubber dies it usually does one of two things:
It cracks, shrinks, dries out and gets hard as a piece of wood.
It melts into a soft gooey jelly that is very messy to clean up.

So replacing your harmonic damper with a second-hand damper that may cost you just as much as a rebuilt damper means that it is inevitable that you will have to replace it again soon.

It also puts your precious automobile's engine at risk of catastrophic failure.
Check out our other blog posts to find out why.

We are totally happy to repair and re-rubber any second-hand or original OEM damper for you before you put it on your vehicle.

Care for your engine by buying it a re-manufactured damper/pulley or a new damper.

v12 Jaguar Etype before repair

v12 Jaguar Etype after repair before painting

Information for our International : US & UK Customers

Below is information which I have compiled for International inquiries. I hope it helps answer your concerns. Please call us or email back if you have any other questions. 

1. When you do send us dampers please email us the date sent, the number sent and what they are, please as parcels sent to us have been mislaid locally and we like to retrieve them but if you don't inform us they are sent, we will never know.
2. Please address the parcel to Harmonic Damper Rebuilds Ltd, 29 Russell St, Waihi, 3610, New Zealand
3. QUOTE: We cannot give you an estimate of the cost of the repair without a photograph of front back and edge of each damper. Having restored quite a lot of Classic car dampers we know they vary widely in how they are constructed and how much time it will take to disassemble, clean and remanufacture them. However when we get the damper disassembled it may prove to need a lot more work than can be estimated by sight.
4. COST: The good news for you is that the NZ$ has slumped in the last few months so any price we quote will likely be 2/3 to half that in your currency. Please check the exchange rate. 
5. As a cost example the Ferrari we rebuilt recently cost $646 NZ including jig making and materials. Our competitors in Australia charge a flat rate of $1000 for jig-making before they charge for the re-manufacturing - just to give you a comparison.
6. FREIGHT: Because dampers are heavy for their size they aren't economical to freight but surface freight (takes 4 weeks by ship) should be the best economy bulk freight bet from the US and UK. You will have to do the sending from your end as all the customs declarations will need to be filled in by you. I'd recommend that if your consignment weighs 20kg - up to tonnes that you talk to a shipping agent.
7. As they are (essentially useless) second hand parts the estimated value of your consignment can be low <$200 and avoid extra tax (GST/VAT) 
8. I don't know about the US or UK but for goods valued at over $400NZ we have to pay 15% on the freight as well as the value of the goods. This is supposed to be changing soon so any value over $20.00 will be taxed at 15% at our end.
9. Alternatively individual damper consignments by post may be the most economical.
10. International courier services vary wildly in their costings and at times their fastest service is cheaper than their slower freight (TNT last I asked) 

Your mileage may vary.

WARRANTY: We are a small quality custom re-manufacturing service so our system isn't fast but you do get a quality 'better than it was new' result and we provide a warranty of our work. See our warranty details on this website.

PHOTOGRAPHS: sending photos of the dampers by email is totally acceptable to us.

Customer Responsibilities are to:-

1. Remove the damper from the engine in an appropriate manner which does not damage it. 
2. Provide accurate timing marks - email photographs of the timing cover or mark TDC on the damper before sending it to us.
3. Providing your full contact details and honest details of the use for the damper eg boating, car, racing.
4. Handling and transporting the damper safely to us.
5. Re-fitting of the damper upon return in a way which does not damage it.

Looking forward to making your precious automobile run better than it has in years, faster, quieter, smoother and with no damage to the engine because your pulley now runs true and does its job.

Send us an email Damperdude - at - gmail.com

Christine and John

Limited Warranty TAC up to 5 yrs

Yes we do warranty our work repairing harmonic dampers.
The basics are :- 12 months unlimited kms warranty, return to our base.
Racing, drags, rallying, boy-racing, and other non-standard driving of the engine are expressly excluded.
For those dampers we make supercharger fittings for, or which are expressly for high performance we will cover on a case by case basis if there is defective workmanship and/or materials for our work.
If you only drive your vehicle occasionally we are happy to extend the warranty to 5 years.
If you are re-selling/passing on our work to another person/company we regret that we cannot extend our warranty to cover third parties (or more) without our express permission.
We particularly exclude original equipment manufacture (OEM) faults and materials from this warranty - since the remanufacture of the pulley relies upon re-use and repair of OEM parts.
Damage to the damper before it reaches our workshop is also expressly excluded from this warranty and repair of bent or broken parts will cost extra.
If the fault is not found to be our workmanship after we have repaired it at your request an additional full hourly charge for all time and materials will be made.

Customer Responsibilities are to:-

1. Remove the damper from the engine in an appropriate manner which does not damage it. 
2. Provide accurate timing marks - email photographs of the timing cover or mark TDC on the damper before sending it to us.
3. Providing your full contact details and honest details of the use for the damper eg boating, car, racing.
4. Handling and transporting the damper safely to us.
5. Re-fitting of the damper upon return in a way which does not damage it.

If you don't know how to do these things please ask us. damperdude (at) gmail.com or call 0064  7  863&3143

In all cases New Zealand consumer law and New Zealand laws apply to all transactions.

Harmonic Damper History - Who invented crank pulley balancers and why?

The inventor of the harmonic damper was Dr Frank Lanchester. He and two of his eight brothers started the Lanchester Engine Company in 1900. They had high standards for their engines and Dr Lanchester would tinker with each motor that went out the door to make it more perfect than the last one. He invented the Torsional Crankshaft Damper [harmonic damper] and the harmonic balancer to cut vibrations in the Lanchester 38 hp six which was introduced in 1907. In 1910 he invented the single and double counter-rotating balance shafts. The patents for which were purchased in the 1970s and used by Mitsubishi and licensed to other manufacturers to the present day. He also invented the steering wheel, amongst many other things.

Luke Brennan has corrected our account with more recent information: You may wish to refer to him as Frederick W. Lanchester. Fred, not his brothers Frank or George.

His damper patent was 12th September 1910. He licenced this to Daimler shortly thereafter. Not Frank – Fred.

Also you may also wish to read the superb “Royce and the Vibration Damper” by Tom C. Clarke, which casts strong doubt on the primacy (though not the brilliance) of Lanchester.

It would now appear that Henry Royce had developed a friction-based harmonic damper for his 30HP engines in 1906 but had failed to patent it.

Royce then developed an extremely effective spring-drive/viscous damper that was used on all RR vehicles until the 1950’s. 

Thanks Luke, as you can see, the inventors of things can be mis-reported or debated, they are long dead so who knows who really did what and when?

Harmonic dampers are called by a wide range of varied names. In truth they are all torsional vibration dampers. Terms like crank pulleys, balancers, power pulley etc are to varying degrees erroneous. The term harmonic balancer comes from some manufacturers using the hub as a convenient location for external mass balance weights. The reason for this is that it made fine tuning of engine vibration simply done by adding or removing weight from the mass balance.
Though it is common belief that large steel parts such as crankshafts are rigid and inflexible this is not true, when a force acts on a crankshaft it bends, flexes and twists just as a rubber band would. While this elastic deformation is often very small it can have a significant impact on how an engine functions.
All objects have a natural frequency that they resonate or vibrate at when struck. An everyday example of this is a tuning fork. The sound that a particular fork makes is directly related to the frequency that it is vibrating at. This is it's natural frequency which is dictated by the size, shape and material of the fork. A crankshaft is a series of tuning forks in a line, it has a natural frequency that it vibrates at. When an object like a crankshaft is exposed to a heavily amplified order of it's own natural frequency it will begin to resonate with increasing vigor until it vibrates itself to pieces. This is called fatigue failure.
Crankshafts twist back and forth a small amount every time a cylinder has a power stroke. This motion is complicated because the amplitude of the vibration varies along the shaft. The crankshaft will experience torsional vibrations of the greatest amplitude at the point furtherest from the flywheel or load.
Engines have major and minor critical rpms and are different due to the fact that some harmonics assist one another producing large vibrations whereas other harmonics cancel each other out. Major critical rpms have harmonics that build on one another to amplify the torsional motion of the crankshaft. Conversely, minor criticals are at rpm that tend to cancel and damp the oscillations of the crankshaft. If the rpm remains at one of the Major criticals for any length of time fatigue failure of the crankshaft will result. These major critical rpms are dangerous and must be avoided or properly damped.
The oscillation of an undamped crankshaft at a major critical speed will commonly shear the front crank pulley and/or the flywheel from the crankshaft. I have seen hub keys sheared, flywheels loose, and pressure plates coming apart. These failures have often required crankshaft and or gearbox replacement and in extreme cases the diff.
Technically, 'the primary purpose of a harmonic damper is to cancel out third harmonic distortion by using intermodulation between the second harmonic and the fundamental in the space charge regions of the triodes.'
Put simply the harmonic damper works by relaying resonance and torsion energy out of the crankshaft and dissipating it as heat by flexing a heavy metal inertia ring which is mounted on a vulcanized rubber cushion. Essentially the damper is a simple spring of rubber plus a vibration and heat absorbing mass - the hub and inertia ring.
Harmonic dampers are made of cast iron for the primary reason that cast iron has the ability to absorb and dissipate large amounts of energy because of it's high specific gravity. The damper on each engine is designed for the specific range of vibrations that a particular engine produces. Keeping the damper cool is also of primary importance.
The key weakness of the harmonic damper is the rubber. Next blog we will cover signs your harmonic damper or crank balancer is dying or dead - it's serious engine damage ahead if you keep driving it vibrating like that folks.

Ford Thunderbird repaired ready for painting.

Porsche 944 damper alteration to run a supercharger.

The Job:- to drive the supercharger faster. To provide more boost pressure to the engine requires a larger diameter pulley than the standard Porsche 944 3 litre four cylinder engine damper.

The solution John found: He machined a new steel belt drive pulley ring for the supercharger which runs over the existing damper on the same belt drive line as the original but on a larger diameter belt drive line.
The damper itself was bonded, re-rubbered and strengthened with a custom made hub turned up from a special grade of  aircraft aluminium which was positioned in the centre of the damper hub to provide additional support to the hub because the original is only a thin steel pressing.
As the original inertia ring could not be altered because of its design the new pulley was attached to the hub of the damper via the new aluminium hub. The whole was bolted together, balanced and polished
Today Graeme, the owner of the Porsche 944 called to say that the modification is successful and that he has raced his machine successfully in two races.

This modification is not cheap but it is an effective solution for a racing car with limited space for modifications. If you seek an innovative solution to a supercharger issue like this give Damperdude a call or drop us an email damperdude . at . gmail. com.

Harmonic Dampers - Who Cares? We do.

What is a Harmonic Damper? 

Why should I be bothered about it when I am rebuilding my engine?

In the eight years we have been repairing these automotive parts this is our most often heard query, even from experienced mechanics and engine rebuilders.

• Harmonic Damper or Torsional Vibration Damper is the correct name for the crankshaft balancer or pulley which is on the front of the crankshaft of your car, bus, truck or boat engine. It absorbs critical vibrations in your engine which would otherwise cause the crankshaft to fail and the vibrations would rapidly wear out other engine and vehicle components.
• There are hundreds of harmonic damper designs but the most common design uses a metal hub with a spigot on which the oil seal runs. On the outside of the hub is a layer of rubber and on the outside of that is an inertia ring of metal. 
• The damper works because usually they are made from cast iron, which of itself absorbs vibrations, the rubber also absorbs vibrations acting as a spring and the inertia ring dissipates harmonic vibrations in kinetic energy and heat. 
• The design of each damper has been engineered to match the vibrations set up by your engine. This means that just any old damper or balancer won't work on your engine, you must use the one that was manufactured for your engine.
• Rubber tends to last only about 10 years, after then it breaks down becoming either shrunken and hard, or soft and gluey. At this point the harmonic damper ceases to do it's work and wear will occur in your engine.
• Most engine rebuilders only consider the harmonic damper as the very last item they have rebuilt on an engine; some rebuild the engine and ignore the damper altogether. This is a mistake as if the engine needs rebuilding then likely the damper will need it too.
• Rebuilding an engine several times because of damage caused by a malfunctioning harmonic damper can be very expensive.

Our small team are working every day custom remanufacturing to as-new or better standards Harmonic Dampers for dozens of different makes and models. 

Contact us 

• If your engine is vibrating at different speeds
• If you are rebuilding your engine
• If you are a collector of classic cars and engines

damperdude - at - gmail.com

Our service isn't fast or cheap but it will provide you with many more years of comfortable safe driving in your precious collectible car, truck or boat.

Yes we are based in New Zealand and yes we do trade internationally. We accept credit cards, paypal and payments direct to our bank account.

International Fire Truck before restoration - note rubber distortion

Buick 1950s before restoration

Buick after restoration with custom made rubbers

Cadillac after rebuild with new hand laid rubbers inside

Copyright Harmonic Damper Rebuilds Ltd 2019

29 Russell Street Waihi

3610 New Zealand