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Trade Customer Rewards!!!!

have-a-drinkGive us a call to find out how you can have a drink on us this Easter long weekend.  Southside Cylinder Heads, Engine Reconditioning Australia is Queensland and Brisbane’s best for Cylinder head repairs and full engine rebuilds.  

Minimum repairs, standard rebuilds and performance upgrades are all catered for. Easter promotional offer is only valid for trade customers

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All About Cylinder Head Hardness

With the advancement in engine technology more components than ever before are being manufactured out of aluminium.  The 70’s and 80’s seen the introduction of aluminium cylinder heads into mainstream family cars and now almost all new engines use aluminium heads and in many cases an aluminium engine block as well.

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Southside Cylinder Heads
Digital Hardness Tester

Although both strong and light, aluminium is also a relatively soft metal that needs to be alloyed with another metal in order to have enough hardness to be used in an engine.  Typical alloying compounds are silicon manganese, copper manganese and iron.

When we talk about cylinder head hardness it is basically the ability of the component to resist being permanently deformed when a load is applied. Testing the hardness of your cylinder head is a vital part of the reconditioning process and the most widely used hardness test in the automotive field is Brinell Scale.

Depending on the manufacturing process and alloying metals used, cylinder heads will have different hardness levels from new, so for instance a new Mazda 6 cylinder head may be 125hb but a Toyota Corolla head may be only 110hb.  You would expect a new cylinder head to be in the vicinity of 100-130hb.

The only accurate way to test your cylinder head hardness is with a calibrated digital tester.  Our testing is conducted in 3 spots on the gasket face of each cylinder head and the average result is recorded.  Industry standard minimum hardness is 65hb and any heads with a reading below this level are unsuitable for reconditioning and must be replaced.  Unfortunately many workshops still use the outdated and unreliable manual “ball tester” that relies on a ball bearing in a tube to bounce above a line.  This type of tester is relatively cheap but has proven to be inaccurate in determining a cylinder heads suitability for reconditioning.

What causes the hardness level to deteriorate?

The single biggest factor that effects your cylinder head hardness is excessive heat.  Most modern engines operate at a temperature of approximately 88°c – 105°c.  When your engine overheats and exceeds its normal operating range, the increased heat puts major stresses on the aluminium cylinder head and starts to deteriorate the hardness value of the head.

Once the temperature of the aluminium reaches about 200°c – 250°c permanent softening of the alloy begins and the hotter and longer your engine is exposed to these conditions the more damage is done.  To minimise the damaging effects of overheating be sure to switch off your engine at the first signs of overheating and have your vehicle checked.

What will happen if I use a soft head?

Using a cylinder head that is soft (tested at 65hb or less) greatly increases the likelihood of premature head gasket failure as it has lost its structural integrity and ability to withstand load and stresses that occur during engine operation.  As well as gasket failure a soft head may also be more susceptible to warping and cracking as the weakened component continues to be subjected to the high loads and stresses of the combustion engine.

A key sign to look out for is head bolt recess or indentation caused when the load applied by the head bolts is too great for the soft aluminium and the bolts will start to sink into the head. These bolts pulling through the aluminium will prevent the correct load being applied to the head gasket and failure will be imminent.

If you have overheated your engine and suspect the cylinder head hardness may be affected, or you just want to be on the safe side, bring your head in to us and we can do a hardness test while you wait (in most cases), and best of all its free!

For more information on cylinder head hardness check out: http://www.aagaskets.com.au/PDF/CylinderHeadResearchInvestigation.pdf

 

 

Southside Cylinder Heads New Equipment

In the recent weeks, the team at Southside Cylinder Heads and Engine Reconditioning Australia have been able to upgrade and purchase two NEW and exciting pieces of equipment to further improve our already outstanding quality and service for you, our valued customers.

Warblaster Wet Media Blaster

We have now upgraded from our old dry blaster to a a brand new locally built wet media blaster, known as the “Warblaster”.southside_cylinder_heads_service_wet_media_blaster-400x300

Built right here in Brisbane, this will improve the finish and speed up the service times for all our Cylinder Heads and Engine Components.

The wet media blaster system propels a slurry of abrasive media and water against the work surface using a special  pump and compressed air, producing unique finishing capabilities and advantages such as eliminating dust, reduced media impingement, reduces stress on the components and produces a deep  clean on surfaces without chemicals.

CompAir L22 Air Compressor

We have also been lucky enough to purchase a new CompAir L22 variable speed screw air compressor.southside_cylinder_heads_service_air_compressor-320x200

The L22 is a variable speed compressor incorporating the very latest technological advances and manufacturing processes to provide users with a continuous supply of economic and reliable quality compressed air, thus improving turn around times on jobs meaning we can service our customers more efficiently.

Hopefully with this new technology we can also work towards offsetting the skyrocketing electricity bills we are all facing.

Southside Cylinder Heads, Engine Reconditioning Australia new Wet Media Blaster and Air Compressor will make the repairs and reconditioning of your cylinder heads and engine components quicker and improve efficiently and quality of our products. Please remember you can charge to your Capricorn account.

We can pick up and deliver anywhere from Brisbane and the Gold Coast suburbs, to the wider regions of Queensland and Northern New South Wales. We are a MTA and RACQ Approved Service Center.

Camshaft Scissor / Preload Gears

The scissor gear on a camshaft is designed to reduce the free play between the camshafts and eliminate any knocking noise by ensuring constant contact is being made between two mating gears.  Basically a spring loaded gear applies constant pressure on the sister gear in order to prevent any rattle or ticking noises occurring.

Fit the service bolt before removing camshafts

The best approach when handling these types of gears is to install a service bolt through the scissor gear BEFORE removing the camshaft.  Most of the time a 15-20mm long 6x1mm bolt can be used, however some applications may vary from this size.  After you refit the camshaft, simply remove the bolt and away you go.

If the camshafts are removed without installing the service bolt, the preload on the gear will be lost and you will have to reset it before re-installing the camshaft.

 

To reset the preload on a scissor gear secure the camshaft in a vice on a section that will not damage the lobes or journals.  You will need to rotate the scissor gear against spring pressure until the service bolthole lines up with the thread.  Normally a large pair of pliers or multi grips will be sufficient to do this.  Holding the gear in place with one hand fit the service bolt all the way through the gear. The bolt only needs to hold the preloaded gear in place and does not need to be any more than finger tight.

Once you have re-fitted the camshafts onto the cylinder head remove the service bolt BEFORE rotating the camshaft, if you try to turn the engine over with the service bolt fitted it will cause significant damage to the engine.

The noise caused by an incorrectly set scissor gear can be similar to a noisy hydraulic lifter or tappet.  After a cylinder head service many people make the mistake of assuming a hydraulic lifter or tappet clearance is causing an excessive ticking or rattle, but often it is the scissor/preload gear that has not been set.

Kia Rio 1.5L 2000 – 2005. Engine- A5D

Head Bolts & Maintenance Issues:

This engine consists of two head bolts at the front of the engine that are shorter than the rest. The two shorter head bolts must be fitted in the corresponding holes at the front of the engine. Fitting the longer bolts in the shorter bolt holes will cause the head bolt to bottom out and the head gasket will not seal correctly. This will result in water and oil mixing, water entering the combustion chamber in cylinder one, and external oil/water leaks around the front of the engine.

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These engines are also notorious for seizing camshafts as a result of poor maintenance and lack of oil changes. If you have an engine with a broken belt, be sure to check under the tappet cover for signs of oil sludge formation. If sludge build up is present, there’s a  good chance one or both of your camshafts have seized in the cylinder head.

Alternately, if your engine is still running ok but you know you’ve been a bit slack with servicing (doing more than 15,000kms without an oil change or using low quality oils), its best to check under the tappet cover for signs of sludge. If you find signs of sludge build up, you should talk to your local mechanic or give us a call as soon as possible to avoid costly engine damage.

NISSAN YD25DDTi

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There are an increasing number of reports of lower timing chain failures in Australian released Nissan YD25DDTi engines. The primary (lower) timing chain and gears are a simplex (single row) design, while t

he secondary (upper) timing chains and gears are a duplex (double row) design. The simplex chains are stretching and ultimately falling, leading to major engine component failure, including valve and piston crown contact and dam

age. It is advisable to replace the simplex timing chains and tensioners before 80,000kms.

Typically the timing chain guides and the vacuum pump timing chain sprocket and shaft are found to be heavily damaged and/or worn as well.

 

Warning on the use of Hylomar!

Most of the head gasket designs available for aftermarket use can be classified into two general categories – Composite and Steel (MLS).  Typically composite head gaskets have a steel core, usually perforated, with softer facing materials (graphite or aramid fiber) bonded on each side.  Until recently steel head gaskets consisted of four to six layers of steel bound together by a variety of mechanical methods however the trend now is for fewer layers with three or two layers not uncommon and even a single layer now in use on some applications.  Also common to these head gaskets is an impervious silicone coating or viton rubber sealant bonded to the outer layers, a key characteristic in the ability of the gasket to “cold seal”.

Gasket

 Generally speaking, almost all aftermarket head gaskets (both composite and MLS) are designed to be used without additional chemical sealants (i.e. hylomar).  The use of an additional chemical sealant on gaskets not designed for it will actually do more harm than good and affect the gaskets ability to seal.

The use of additional chemical sealants such as hylomar can affect the head gaskets ability to:

  • Cold-seal, the ability of the gasket to seal coolant until the engine is first started.
  • Cold Flow, the characteristics of the coating material to creep as the gasket is loaded (clamped), to seal small scratches and imperfections on the head and block surfaces.
  • Reduce the shearing forces that are applied to gasket sealing surfaces by thermal expansion of the cylinder head and block
  • The added thickness of an applied sealant on a head gasket can cause uneven loading and or a loss of torque retension.
  • The use of an additional sealer may also cause relaxation when temperature is introduced

Some chemical sealants may also react with the gaskets silicone coating, causing the gasket to deteriorate, and in some cases can cause the deterioration of the chemical sealer itself.

The vast majority of gaskets supplied by Southside Cylinder Heads will not require any additional sealants and the use of such products is not recommended, and may void the head gasket’s warranty.  Please read the gasket fitting instructions before fitting your next head gasket, or simply give us a call if you are unsure if your head gasket requires an additional sealant.