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Discussion Starter #1 (Edited)
Hello Everyone,

I was hoping someone could shed some light on this little obstacle that Im having. Im going to try and explain this as best as possible considering that Im a lamane. Here is the issue, yesterday a friend of mine and I were installing pistons on my 1973 Alfa Romeo GTV and we came across a problem.

Per my understanding- the arrow on the top part of the piston needs to go to the exhaust side correct?

Three of the pistons were fine however when we attempted to install #4 piston the connecting rod seemed different. What Im trying to say is that possibly someone reinstalled the connecting rod on the piston incorrectly such as the machine shop when they cleaned my pistons or the previous owner did this.

My question is.... "which way does the tong face or the notch on the connecting rod.." I want to make sure that the pistons are installed correctly...

I hope this makes sense, if anyone can answer this question ASAP I would really appreciate it!!
 

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Yes, those arrows stamped into the tops of the pistons should point toward the exhaust side. The direction of the arrows matches how gas passes through the combustion chamber: from intake toward exhaust.

Note that the rods have to be aligned properly too - they are not symmetric. If you put a piston in backwards, it may slap more, but the engine will run OK. Put a rod in backward, and bad things will happen.
 

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The rods are offset, front and rear. They should be numbered, so all you should need to do is be sure all of them are correct. Hopefully someone here will post the picture from the engine manual showing the offsets.

Sounds like one rod is backwards (so that the offset goes the wrong way). Pull out the circlip and pin, rotate the rod, reinstall.

Robert
 

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Good that you understand that there may be a problem. I suggest you stop until you understand how the rods have to be oriented to the crankshaft and then how the pistons are oriented to the rods and block.

This is best done by using a repair manual which all that I have seen have pictures showing the orientation of the rods.

Many have made a mistake with rod orientation and ruined more than a few Alfa engines.

As the others have said, when the rod orientation is correct, with stock Alfa rods, all the numbers, both rod and cap, will be on the same side numbered 1 to 4, front to back, and the piston arrow points to exhaust side. Rod 1 would have cap 1, Rod 2 cap 2 etc.

Second pic is caption for first pic. Third you will need later.

Good luck
 

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And, the rod numbers are on the exhaust side as well - correct?

Thanks!
 
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