Here is some background to my question. I have a 83 nautique with a Mercruiser MIE 260 (Chevy 350 small block). I've had the boat for 12 years and used it frequently with no hassle. The motor is a RH/reverse rotation. The timing works with a gear. The crank rotates reverse and everything else (camshaft/oil pump/ distributor) rotates normal. The firing order is reversed (12756348). One of the push rods bent so I had to strip the engine.
I ended up buying another motor which turned out to be a bad buy. This was a LH rotation working with a timing chain (crank and cam rotate the same direction-LH). I ended up using the crank, camshaft and pistons from this motor and put it in the original block. The camshaft from the original motor somehow went missing. The pistons, as in the original motor was turned around, and the main bearing seal is different for the reverse rotation, which is the only difference I picked up from forums (and comparing to the original motor). My uncertainty is around the camshaft I used from the LH rotation engine. I cannot get certainty if the camshaft should be different to a LH rotation, since it still turns the normal direction.
After assembly the motor does start but blows air back out the carburettor and then shortly thereafter dies.
Looking for the part on amazon (Small Block Chevy MARINE REVERSE ROTATION Engine Camshaft Melling 22125) it states "REVERSE Cam ROTATION ENGINES ONLY !!!, IF you have a chain drive timing set, and the cam AND crank BOTH turn REVERSE you do need this. IF you have a 2 gear timing set, and the cam and crank turn OPPOSITE directions from each other - you do NOT need this, you need a standard marine cam". This suggests I need a normal camshaft.
I need to import the part which will be pricy and do not want to end up buying the wrong thing. Hence, my questions are, can I use a standard rotation (LH) camshaft or do I need a reverse rotation camshaft? and why else would the air blow out the carburetor?
I ended up buying another motor which turned out to be a bad buy. This was a LH rotation working with a timing chain (crank and cam rotate the same direction-LH). I ended up using the crank, camshaft and pistons from this motor and put it in the original block. The camshaft from the original motor somehow went missing. The pistons, as in the original motor was turned around, and the main bearing seal is different for the reverse rotation, which is the only difference I picked up from forums (and comparing to the original motor). My uncertainty is around the camshaft I used from the LH rotation engine. I cannot get certainty if the camshaft should be different to a LH rotation, since it still turns the normal direction.
After assembly the motor does start but blows air back out the carburettor and then shortly thereafter dies.
Looking for the part on amazon (Small Block Chevy MARINE REVERSE ROTATION Engine Camshaft Melling 22125) it states "REVERSE Cam ROTATION ENGINES ONLY !!!, IF you have a chain drive timing set, and the cam AND crank BOTH turn REVERSE you do need this. IF you have a 2 gear timing set, and the cam and crank turn OPPOSITE directions from each other - you do NOT need this, you need a standard marine cam". This suggests I need a normal camshaft.
I need to import the part which will be pricy and do not want to end up buying the wrong thing. Hence, my questions are, can I use a standard rotation (LH) camshaft or do I need a reverse rotation camshaft? and why else would the air blow out the carburetor?
notes to see details such as 'use with a 1- or 2-piece rear main seal, (in which your new engine sounds like it changed seal designs) etc. as the list goes on and on including oil pan + mounting hardware size, etc..
