Resurfacing Flywheels

By | Library

What is Resurfacing?

Through normal use the surface of a flywheel can become worn, pitted or discoloured. Due to the surface being uneven, it doesn’t meet the clutch smoothly which results in clutch slippage or uneven wear and tear.

To remedy this you can remove imperfections by grinding or cutting, resulting in a smooth surface that meets the clutch evenly. Generally you address this when changing the clutch as this process will expose the whole assembly for inspection, allowing you to resurface or replace parts depending on their condition.

When removed you can perform an inspection using a straight edge and feeler gauge to determine its condition.


Why is Resurfacing Performed?

A resurfaced flywheel will have a completely even surface with no flat/hard spots of material. This means the friction across the whole face will be even, making engagement more predictable and smooth. It will also ensure your new clutch is broken in and wears evenly, allowing you to get the full life out of it.

The biggest advantage is more torque can be held by the assembly without slipping, prolonging the life of your clutch. It also makes for smoother and more predictable engagement, making the vehicle easier to drive. As the parts are already accessible when changing the clutch, preventing any premature wear by resurfacing doesn’t involve much more labour or cost.


It’s also a good idea to inspect the flywheel before any resurfacing is performed. Any signs of cracking means the part is unsafe to use and should be replaced immediately. Cracked flywheels can explode whilst in use, which will require a new gearbox as well as serious injury!

On many flywheels the starter ring gear is a separate component, that’s pressed on at the point of manufacture. As it’s a replaceable part ensure that no teeth are damaged. If you can’t replace the teeth and there is damage, it’s strongly advised to source a replacement.



You will need to consult your vehicle manufacturers tolerances, as material will be ground away to create an even surface you need to ensure this is within manufacturer specification. If there isn’t enough material to remove it will need to be replaced.

It’s also important to ensure the machined surface is flat and completely free from defects.

If resurfacing is required it’s a good idea to mark the index position in relation to the crankshaft prior to removal. This is vital with engines that are externally balanced using flywheel counterweights. This step isn’t necessary if the engine is internally balanced.

Dual Mass Flywheels

It’s not recommended to resurface all DMF’s specifically from BMW, General Motors or Porsche. If the flywheel on any of these vehicles is worn it should be replaced.

Other manufacturers such as Ford are able to be resurfaced, once removed you need to separate the primary and secondary flywheels and resurface within manufacturer tolerances. All bolts should be replaced prior to replacement.


How to Resurface a Flywheel

The two methods of resurfacing involve cutting or grinding. Cutting will be performed on a brake lathe, care needs to be taken to insure the flywheel turns true on the lathe. This is so that every area of the face is cut evenly to provide a smooth mating surface for the clutch. The cutting of material is performed using a lathe, with the advantage of removing smaller amounts of material compared to grinding. The disadvantage of cutting material away is it doesn’t address hard spots of material, leaving uneven areas.

Grinding is the alternative to cutting, and is generally the preferred method of refurbishing a flywheels surface. Although the disadvantage of grinding is more material is removed, a grinder will remove hard spots of material.


Symptoms of Failure


The most common indicator is vibrations at idle or low speeds. You can also feel the chattering through the pedal, and experience erratic behaviour when the clutch engages. Usually these vibrations are caused by a failed spring mount mechanism of the flywheels, therefore reducing the ability to absorb vibrations from the engine/drivetrain usage.


Burning Smell

Another indication of failure is a burning smell in the cabin, some describe the smell as burnt toast. The smell is caused by too much heat on the contact faces, this can also happen due to improper driving. If the smell is only temporary after slippage there shouldn’t be any lasting damage, and won’t require a replacement.


How to get Cigarette Smell out of a Car

By | Automotive Detailing


Not only is cigarette smoke an unpleasant odor, it’s difficult to remove from your car – however not impossible.
Here’s what’s worked for us:

1. Dispose all cigarette butts and ash from the car
2. Clean the ash tray and every other surface that’s come into contact with cigarettes
3. Deodorize all fabric surfaces
4. Clean all glass
5. Treat the HVAC ducts
6. Soak up the scent using household products


It makes sense to start with the source of the smell, therefore helping to rid the odor as quickly as possible.

Remove all Cigarettes from your Car

Cigarette butts and ash will keep your interior lingering of smoke, despite any effort you make to mask the odor. Start by cleaning out your ash tray and vacuuming the whole car, removing the source of the smell.

Vacuuming and shampooing all Fabrics

All soft fabrics in your vehicle need to be vacuumed, as odor particulate will accumulate into the material. If you hire a professional to tackle the job, they will perform a complete shampoo of seats, carpets, door panels, headliner and Air Conditioning vents. Read our full guide explaining how to clean car seats.
Consider performing the same thorough cleaning to completely eliminate the scent from returning, expect to shampoo the interior multiple times if smoking heavily.

Glass Cleaning

Nicotine will cling to all surfaces relentlessly, including glass. Not a place you may expect to be causing bad smells, but it’s something that can be quickly remedied using a white vinegar in a spray bottle.

Spray the white vinegar on the glass avoiding any interior trim around the glass, and wipe away with a damp cloth. If this solution doesn’t work, you can mix ammonia and water in a 1:16 solution of ammonia to water. Spray onto glass and use a lint free cloth or newspaper to wipe the surface dry.


Your cabin filter which filters air before entering the cabin will need to be replaced. The filter will trap the odor and keep the smell lingering when you use your vents. Each manufacturer has a different procedure to replacing cabin filters, however it’s a common service item and should be easy to find online or in your vehicle handbook.


Absorbing the smell

Using Everyday Objects:

Ground Coffee

For decades ground aromatic coffee has sparingly been used to absorb smells by truck drivers in their trailers. Due to its absorbent properties it’s perfect for removing remove smoke odor from your interior.
Simply fill up bowl or two and fill with coffee. Leave in the vehicle with the windows and doors closed for 24-48 hours to absorb the odor. Depending on the cars exposure to smoke, this treatment may be more than enough to completely clear the smell, however it’s easy enough to repeat should your car require multiple treatments.
It’s not a good idea to drive with open bowls of coffee in your car, however you could fill up a few pairs of tights and tie the end to keep it secure.


Similar to coffee charcoal is excellent at absorbing bad odors, which you can use instead of coffee if you don’t like the scent. Simply leave charcoal or charcoal briquettes in a container and close all openings of your vehicle.
When you return 24-48 hours later your car will no longer smell, just simply dispose of the used charcoal.


Newsprint is another great way to absorb potent smells. Roll up a few newspapers and place them under your seats. Within a few days you will notice the smells fading away, and you can periodically change out the newspapers to maintain the absorbing process.

Cat Litter

Extremely absorbent and easily available, cat litter is very porous and will soak up bad smells quickly. A great alternative to the above method if you already have cats, and has the added benefit of absorbing moisture within your car too.

White Vinegar Spray

Not a personal favourite of my own, however white vinegar sprayed onto fabric surfaces will get rid of the source of odours. Mix a 50:50 spray bottle of water and white vinegar, then spray onto your interior fabric.
Be sure not to spray onto any electrical devices or suede interior. I personally can’t stand the smell of vinegar, you have been warned!

Baking Soda

Among bicarbonate of sodas many uses, a natural deodorant is one of them. Firstly sprinkle the baking soda over as many porous surfaces as possible (Floor Mats, carpeting, seats) and work in using a brush.
Then go ahead and wait between 30 minutes to a whole day before vacuuming up the baking powder. The longer you leave it resting in the fabric, the more likely it will deodorize your interior.
When vacuuming, take at least two passes to ensure all residue has been removed.

Commercial Products:

If using our household solutions haven’t killed the smell, turning to purpose made products will rid that odor once and for all!

Ozone Generator

A machine that creates ozone gas from carbon dioxide. Ozone will react with particulate and bacteria, therefore neutralizing the source of bad smells. These machines are available to buy or rent, and are used in many different applications to remove bad odours.
It should be noted that caution should be exercised when using an ozone generator, as they’re harmful to health. By breathing in ozone it can cause respiratory issues, and should only be used in uninhabited areas that are sealed off.

Dakota Odor Bomb

There are many products available that you can use to deodorize your vehicle. Press the button onto the can until it locks fully, put it on a flat surface in the car and shut all openings.
After 2 hours, ventilate the vehicle to allow the product to escape. There may be a chemical odor that lingers for a few days, however this is a great alternative to an ozone generator and easier too.

Ferrari F1 Transmission Pump Issue

By | troubleshooting

As the beloved 360 is aging, so are the components responsible for its smooth operation. In this article I’ll be running through a fault with the F1 transmission in the 360, causing issues with gear changes.

This issue can be intermittent or cause full failure of the transmission, leaving you unable to select gears. See our symptom list below to see if this is what you experience, instead of aimlessly replacing parts.


  • A flashing red transmission light on dash, accompanied by problems engaging gears.
  • Intermittent issues with getting into gear, can be permanent depending on the type of failure.
  • When you first open the driver’s door, you will hear a loud whining noise – this is the pump priming the transmission system. You will want to listen out whether this happens every time you come back to the car after it’s been sitting a while. If you don’t hear this noise, and face problems shifting it’s associated with a failed transmission pump.
  • When changing gears even stationary, no sound from the actuator can be heard.

Things to also check

Before throwing parts at your vehicle, some basics to check are:

  • Transmission Fluid Level: A slow leak may develop leaking fluid over time, this can lower the pressure rendering your F1 transmission unable to engage gears.
  • Bleeding: If any components have been replaced that can introduce air into the system, check the fluid has been bled correctly. If air is present in the system, you will have issues selecting gears.


It’s also worth fixing

  • The relay which drives the transmission pump. This relay can get stuck open, causing the pump to run for longer than required causing premature failure. As the pump is much more expensive than the relay, it’s worth replacing both as it’s a common point of failure.


The F1’s transmission relies on a pump to provide pressure to the system. If the pump fails, so does your ability to select a gear. Fortunately, this isn’t a difficult issue to fix, nor particularly expensive.

Before we get started, it’s important to note the pump is two separate sections; the pump itself and the motor. The point of failure is the motor in most cases, fortunately you can replace the motor without having to bleed the system. If you replace both the pump and motor, you’ll leak coolant everywhere and air will be introduced into the system.


Tools Needed:

  • 1 x 10mm
  • 1 x Torx T30 Bit


A great video walkthrough can be found here, documenting the whole process.


The pump and motor assembly can be purchased from the dealership for around $1,000, alternatively a near identical part, still manufactured by Magneti Marelli can be purchased for around $250.

There are a few subtle differences in appearance, however both serve the same purpose of driving a pump.

Here are links to both – try and spot the differences between them both!

Privacy Policy

By |

Privacy Policy

Effective date: July 15, 2018

Amansworldco (“us”, “we”, or “our”) operates the website (the “Service”).

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We collect several different types of information for various purposes to provide and improve our Service to you.

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While using our Service, we may ask you to provide us with certain personally identifiable information that can be used to contact or identify you (“Personal Data”). Personally identifiable information may include, but is not limited to:

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Legal Requirements

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What’s the difference between a Moonroof vs Sunroof?

By | Library

You may have heard moonroof and sunroof used synonymously, however there is a distinct difference between both. It can be hard deciphering the difference on your new cars option sheet, so let’s get straight into it.


A sunroof includes two types of panels, the first being a retractable panel mimicking the headliner. Once fully retracted will expose the glass panel above. The second is another panel made of glass which can be tilted open or fully open, essentially serving as an open window in the roof.

You’ll commonly see wind deflectors or wind nets used with a sunroof, otherwise you will hear whistling and air passing over the gap when travelling at speed.

Interestingly, there are different types of sunroof:

  • Pop-up: A manually operated panel which tilts open.
  • Spoiler: A panel which tilts up and slides towards the back of the car, providing an opening in the roof
  • Top-mount sliding: Mounted to rails, the panel will slide open on the vehicle’s exterior.
  • Inbuilt/Moonroof: Generally electric, this slides between the vehicles metal roof and interior headliner revealing the glass.



Technically a type of sunroof due to it letting air and light through the top of the vehicle. However, the moonroof earned its own name due to its functionality, and ultimately demand on vehicles.

A moonroof will commonly have an interior sliding shade matching your headliner so you can open/close when needed. However, the glass doesn’t retract or open, it’s just a fixed structure within the cabin.

The idea is to let light into the vehicle when desired or using the shade to block light out.

Can I Mix Different Weights of Oil?

By | Maintenance

Using the correct engine oil is imperative to a trouble free, long life from your engine. Sometimes you may need to top off your oil, choosing the correct weight and type specific to your engine ensures no issues further down the line.

But what happens if you don’t have the exact weight of oil needed for your engine. Can you mix different weights of oil?

Weights Explained

Mixing oils isn’t a straightforward yes or no answer, as there are many variables. The first is the weight of oil, identified by “0w30” for example. The first number represents the viscosity in winter, the lower the number indicates thinner oil when cold.

The second number indicates its viscosity at 100C. This is a standard measurement across all manufacturers. The higher the number indicates how thick the oil is, therefore 0w40 is thicker than 0w30 at 100C.

When you mix two different oil weights, its viscosity changes depending on the mixture. For example, if you have a 50:50 mix of 0w40 and 0w30, you’d expect the mixture to end up around 0w35. The issue lies if there is a large discrepancy between the mixed oil weights, altering the viscosity outside of manufacturers specification.

For a quick top off there shouldn’t be any issues if the viscosities are close like our example – providing the manufacturer is the same. Be aware using an extremely thick or thin oil can cause irreparable damage. Using your best judgement here is key.


Oil Types Explained

There are two types of engine oil used, Mineral and Synthetic. Mineral oil is used on older vehicles as it was the standard until more performance was required from combustion engines. A solution was needed to the increased temperatures and strain on oil, so a purer and better performing solution was required.

Synthetic oil has 5 main benefits:

  • It’s resistance to breakdown under higher temperatures is better, ensuring proper lubrication in hot climates or performance cars.
  • Performance in low temperatures (-40C) ensures protection despite being below freezing.
  • Better protection from degradation. Synthetic oils resist shearing much better, maintaining it’s viscosity over the life of the oil.
  • Lower consumption of oil as synthetic blends experience less boil off compared to traditional blends. According to Total, a quality synthetic oil will only lose 4% of it’s weight when exposed to 400 degrees for six hours. Mineral Oil will experience 30% loss under the same conditions.
  • Cleaner engines as synthetics don’t sludge up as fast. This means short trips or driving in winter results in better lubrication and protection.

Is it okay to Mix Different Brands of Motor Oil?

You can mix the same type (synthetic or mineral) from the same manufacturer. Different manufacturers use different additives to achieve the best performance from your engine oil. The issue lies in how these interact with each other inside the harsh environment of an engine – potentially causing failure.

Be careful you’re not mixing different types of oil, only ever mix synthetic with synthetic, and mineral with mineral. If in doubt don’t risk it, you can get oil the next working day from X.

Clicking Noise when Trying to Start Car

By | troubleshooting

Everyone’s been in the same situation, running late in the morning for work when disaster strikes. Your car won’t start, potentially leading to big repair bills.

If your lights come on, radio works, but you hear a clicking when trying to start the car, you’re in luck! This can be narrowed down to either the battery or starter motor in 99% of cases and is easy to diagnose.



Visual Inspection

First on the list is your battery. Most commonly located under the bonnet in plain view, and in the boot in BMW’s. This is the main culprit for starting issues, commonly caused by a worn-out battery from age. Batteries can last anywhere from 3 years to 10 depending on climate, cold weather is harsh on batteries and will shorten their working lifespan.

Remove any covers to expose each terminal and check for a blue/white crystal substance on each terminal. If you see this do not touch, as it’s battery acid that’s leaked from the cells and will cause chemical burns. Corrosion will look like the image below:

Battery acid leak

Instead mix 16oz (500ml) of hot water (not boiling!) with 1 tspb of baking powder, and slowly pour over the terminal. The mixture will bubble up and fizz, neutralising the acid.

Slowly pour clean water to remove the residual baking powder and dry off with a lint free cloth.


Check the rest of the battery for swelling or visible leaks. Inside the battery is a mix of distilled water and battery acid, if this mixture leaks you will see a blue/white crystal substance. Swelling isn’t a good sign either – replace immediately ensuring proper disposal of your old battery.

Terminal Connectors

If there isn’t anything visibly wrong, you now want to check the connections to each terminal are securely attached. To check this, give them a slight wiggle to check for play. You shouldn’t be able to move these connections – if they are loose go ahead and tighten them up.

Check the terminals and connections for dirt and grime, as this can prevent a circuit being formed. An old toothbrush with a diluted baking soda mixture will clean up the connections perfectly.

If you need to remove the connectors, remove the negative terminal (indicated by a -) first, then the positive terminal.

When reconnecting the battery, the positive terminal needs to be connected first (indicated by a +) then the negative terminal.


You can also test whether the battery has a charge by using a multi-meter. An extremely useful piece of equipment that should be in every DIYers toolbox. If you find yourself without one, I recommend the X.

To use simply turn the dial to X, then wait for the display to zero. Touch the negative and positive terminals to the corresponding terminal on the battery and wait for the number to stabilize.


Starter Motor

If your battery passed the above tests, our focus will move onto the starter motor.

If you can hear one loud click or no clicks when turning the ignition, this indicates a problem with the starter solenoid.

What is a starter solenoid?

A solenoid is a coil of wire wrapped into a tightly packed helix shape. This solenoid is then used as an electromagnet, as the device creates a magnetic field from the electric current passed to it when you turn the ignition.

This small surge of current from the ignition turn, creates the electromagnetic field which brings the two connections together, completing the circuit and providing the starter motor with power.

As this is a moving part it’s susceptible to breaking and will eventually need to be replaced. As we can’t provide specific tutorials for each vehicle, I advise you to grab a Haynes Manual which will guide you through the process of replacing starter components.

Why does my Car Smell like Rotten Eggs?

By | troubleshooting

Unusual smells and sounds from your vehicle shouldn’t be ignored, especially a pungent odor like rotten eggs. There are only a handful of reasons why your car will smell like eggs, fortunately this issue is easy to diagnose.


Cracked or Clogged Catalytic Converter

By far the most common reason for this smell is a malfunctioning catalytic converter. The odour is caused by Hydrogen Sulfide, which is a byproduct of combustion. This gas is converted inside the exhaust, to produce sulphur dioxide an odourless (and much less harmful to the environment) gas.


If your catalytic converter begins to malfunction or leak combustion gases, you will begin to smell this mainly at the rear of the car – specifically from the exhaust. (Note: Please don’t inhale your cars exhaust!).

Another symptom is rattling from the converter itself. Inside is a honeycomb like structure which can work loose or disintegrate. If you can remove this from your vehicle, try shaking or hitting with a rubber mallet to see if you can hear movement inside.

You may also see a check engine light on your dashboard, indicating a lack of efficiency from your catalyst. A code reader is a handy tool, which will tell you the corresponding tool – pinpointing the exact


A major reason for your catalytic converter becoming clogged is due to an improperly functioning engine. Excess fuel being introduced into your exhaust can destroy the catalyst inside, resulting in foul smells.

If your engine burns oil, this can cool the catalyst preventing soot from being burned off. Generally these problems can be caused by a wide range of issues from faulty sensors, aging rubber parts or a failing engine – consider consulting a trusted mechanic to inspect your vehicle, or read our troubleshooting guides.


Battery Leaking Acid

A battery being overcharged will produce hydrogen sulphide, causing a rotten egg smell. This is due to the acid inside each cell escaping the casing, as most car batteries are sealed.

It’s easy to identify, as you will see a white crystal substance, typically seen around the terminals of the battery. You may also notice your battery swelling at the sides, due to increased internal pressure.

If your battery is leaking or appears to be swelling, immediately stop using your vehicle and get a replacement is installed.

You shouldn’t touch the battery without wearing proper protection, because the internal acid can cause serious injury to skin, even if it’s dried.


Transmission or Differential Fluid

Petroleum based oils can cause an unpleasant smell once aged or heated outside of the operating temperature range. In older vehicles it’s possible the transmission or differential is slowly leaking fluid, causing a bad odour once up to temperature.

A tell-tale sign of an oil leak is a small puddle in the morning, most commonly the drain/fill plug crush washers – fortunately an easy fix (and excuse to change your fluid!).

Another possibility is a crack in the metal casing causing the leak, carefully inspecting the trail of oil will quickly reveal whether you have a crack in the casing, or simply a leaking crush washer.


In this instance, changing the fluid will cure the odours source. Oil does eventually go bad with age and use, and is easy enough to change with simple tools.

Make sure you inspect the transmission and differential for leaks, to solve the underlying problem of smelling the oil. The leak will most commonly be from the drain and fill plugs, if this does turn out to be the source of the leak your local dealership can provide the correct parts extremely quickly!

A Haynes manual for your vehicle will show you the correct procedure to replace the fill plugs, as well as changing the oil itself. The manuals include pictures and manufacturer torque specs, and are easy to follow.