Cylinder Head Repairs Cam Belt & Valve damaged Heads

This is always a question you are faced with when there has been severe damage to a cylinder head.

But part and parcel of what we do each and every day is a large amount of cylinder head repairs to cylinder heads that at first look like they can't be repaired, especially where a combustion chamber has been completely destroyed.

It very well might be a very slow and extremely time consuming process that entails a massive amount of care and concentration in the case of cam belt and valve damaged heads, and it is not always successful, but we take the time to reconstruct the combustion chamber and all relevant areas to as close to as original as what it was before the failure.

To really illustrate this point, we have attached the text that always goes with a cylinder head that we have repaired at a customer's request:

You have requested that this cylinder head be repaired and SAC Engineering has done exactly this.

It is normally far more expensive to replace the damaged cylinder head with a new one.

Repairing this damage is the economical route and while it is only one of the options available, you need to know the risks that go with this choice.

Please take note of the following: This applies to all welded cylinder heads.

· In order to repair this damage we have needed to expose the cylinder head to excessively high temperatures. Aluminium and / or cast iron welding generates heat that far exceeds any combustion temperatures. The head is normally pre-heated in an oven and is cooled down after all the welding and associated heat in its own natural way. The properties of the aluminium and / or cast iron have undergone changes and are no longer what they were or should be.

· Hand finishing a combustion chamber after extensive welding is a time consuming process and while we will always attempt to match the combustion chamber to the original one, small changes can be found in the shape and size. We have found repaired combustion chambers to be one or two cc's bigger or smaller than the original. To make them exactly the same is virtually impossible.

· It is also very important to find the cause of the initial failure or it will more than likely happen again.

· More often than not it is not the right choice to repair a damaged cylinder head when it requires extensive welding.