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The time has come to install my original pistons into this 226. New .030" under conrod bearings, new rings. First 3 pistons go in fine and I can spin the motor through several revolutions.
I put in #4, same process, and now the motor won't spin more than 1/4 turn without jamming on something even though the #4 conrod isn't on the crank yet or even touching anything. So I can see and move the #4 conrod just fine but the remainder of the motor now only does 1/4 turn.
Top of image is front of motor. Are pistons directional? Did I insert them backwards into the bore? Are the conrod caps directional? Are those backwards..? I've been outside for 6 hours in this 92F day and I'm losing my patience..
Main bearing caps are directional, and need to go back on the same position as they originally were. Usually there is an arrow on the MB caps pointing to the front of the engine.
Con rod caps and rods are stamped with the cylinder number, and go together with the numbers on the same side. See the manual excerpt below. V8 rod showing the oil squirt hole; on the 226 it will be off to the side more.
Pistons have a notch or divit on the forward side. (towards #1)
Pull the #4 piston back out and see if you can rotate it. Is it possible the cam is hitting that rod?
Thanks. I pulled out #2 and #4 and flipped them to correct orientation. #2 was fine both ways, full uninhibited rotation.
When I got #4 back in it once again locked up. Took a closer look to figure out where the hold up was and it seems like the con rod is hitting the counterweight at the con rod cap?
Also I'm wondering if the motor orientation has anything to do with it. I have the motor standing up right now as is crank standing vertically for ease loading pistons. Wondering if that's forcing the con rod into a position it wouldn't normally be in?
Any other suggestions? These pistons turned freely 2 months ago in this bore so I'm stumped. Help please before I yell at another inanimate object..poor bench clamp.
The piston pins can move in the pistons, so the rod just needs to be pushed clear of the counterweight. Having it vertical is causing the problem. But it can also happen in any position.
