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Pushrod length above std?
I did my 3.4 L engine some months ago. The reason for the overhaul was a broken cylinder gasket and severe piston slap when cold.
I replaced a lot of parts including the pushrods at the time. The new rods were 144 mm (exhaust) and 152,5 mm (intake) which is std specification. This length is the only listed both in the genuine service manual an the micro fisch parts catalogue. There are no other lengths available in the parts catalogue!
I measured a lot of the used parts to check for wear when I disassemble the engine and I was quite supprised when I found that the old push rods were approximately 2 mm longer than the std specification.
Is it resonable to believe that GM may use slightly longer push rods when assembling some engines for any reason, possibly a salvage measure for a poor positioned camshaft bore? To allow for proper lifter adjustment in all temperature conditions!
I actually have some valve train sound when the engine is hot which i did not have before the overhaul. Maybe I shall fit the longer rods in the engine again?
Any experience or advice is appreciated!
I replaced a lot of parts including the pushrods at the time. The new rods were 144 mm (exhaust) and 152,5 mm (intake) which is std specification. This length is the only listed both in the genuine service manual an the micro fisch parts catalogue. There are no other lengths available in the parts catalogue!
I measured a lot of the used parts to check for wear when I disassemble the engine and I was quite supprised when I found that the old push rods were approximately 2 mm longer than the std specification.
Is it resonable to believe that GM may use slightly longer push rods when assembling some engines for any reason, possibly a salvage measure for a poor positioned camshaft bore? To allow for proper lifter adjustment in all temperature conditions!
I actually have some valve train sound when the engine is hot which i did not have before the overhaul. Maybe I shall fit the longer rods in the engine again?
Any experience or advice is appreciated!