I pulled the motor on my 1998 Rodeo. I am going to remove the crank, but the manual says the Pistons must come out. I am sure it is obvious to most, but why is it that the heads and pistons must come out? It seems if you remove the mains and the rod caps the crank should come out without removing the others....
I am sure I am missing the obvious. Will someone enlighten me.
Thanks
I'll try to answer this. You can do what you are asking about on an in-line engine, such as a 4 or 6 cylinder, but its orders of magnitude more difficult on a "V" configuration. The reason is that the pistons and connecting rods, with their studs, can't get far enough away from the crank to be able to get all the caps off, hold all the rods away from the crank, and lift the crank straight out. One set is going to bind or keep you from doing it. And the worst part would be in getting it back together - remember, the con rods are now holding new journal bearings.
I think the bottom line is that it is very difficult to position the crank in such a way that you can avoid having at least one set of con rods get in your way when you're trying to pull it.
Another reason is that if you're replacing bearings in the lower end for any reason, it makes sense to pull the heads, replace the valve stem seals, and put a set of rings in the holes... to do any less is simply inviting oil consumption.
Those are my thoughts. Someone may have a better reason. r/ Steve
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