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Discussion Starter #1
Hi,
I hope someone can help with a technical question. I have a blown head gasket in my 73 2000 spider and this is my first atempt at working on an alfa engin. When I took the engin apart I noticed the markings on the top of the pistons, in particullar the arrows. Two face to the exahust side but two do not. As the engin has been running this way should I turn them? If I do need to would it be best to just turn the pistion on the rod or turn the rod as well?
Hope someone can help.
alfannut
 

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the arrows should point in the direction of gas flow, ie gas flows from inlet to exhaust, therefore the arrows on the pistons should point to the exhaust side.
Early alfa engines had no arrows on the pistons as the conrods were centred.
On later engines the conrods had an offset (offset of conrods 1 & 2 and conrods 3 & 4 should face one another), hence the arrows.
If the rods were put in wrong they would not be centre on the piston pins. You would see this.
If i remember, another way to check offset on conrods is (don't hold me to this it has been 20 years since I opened up an alfa engine:)) the rods and the caps have stamps on them - make sure that all the stamps face the one way on the same side of the block.

Others will correct me if I am wrong.
 

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Discussion Starter #3
Thanks,
When you say older engins this is a 73 so if they were not off set but someone rebuilt the engin using new marked pistons it would not matter corect? I will check out the rods to see if they are mixed up as well as the pistons.
 
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