EXPERTS NEEDED - pistons tight - Toyota Nation Forum : Toyota Car and Truck Forums

ekopel · 08-24-2009, 07:28 PM

hello fellow tners.
so..
i just built a brand new 1mz from scratch. new crank that CAME WITH bearings to match it. stock pistons and rods with stock bore. new rings. p and p heads, timing is lined up. cams spun nice, crank spun nice. serpentine belt not attached.

the problem is that i can not get the motor to turn. i have gone through every option and the last thing i can come up with is that i did not put engough lube/oil in the cylinders before i installed the pistons. i have the heads mated now and do not want to pull them. if i can get the pistons to loosen up just enough to turn it a few times, i am thinking it will turn over. i need to turn it without fuel because i need to connect the flywheel to the torque converter.

up for any ideas. crazy or not, practiced or not. i dont have the time to pull the motor out again, so if i cant get it to turn im going to part it out or something.

stuckTaco · 08-24-2009, 07:35 PM

Did you check and make sure the piston is install in the correct orientation? There are usually markings on top of the piston to tell you which direction they are facing. Also when you had the block bored out how much did you have it bore and did you get the correct size piston for that bore. And last did you get the correct ring and size them correctly?

Creeps228 · 08-24-2009, 08:38 PM

how are you trying to turn over the motor, by hand? or by the starter

***ASG14*** · 08-24-2009, 10:37 PM

^ Yeah, I wonder that too.
And as stuckTaco said, there is R and L pistons for the 1MZ.

ekopel · 08-26-2009, 04:18 PM

ok so after talking to my mechanic and plastigaging everything, it turns out i dont have enough bearing oil clearance. im thinking it is either because my crank was not correctly machined, or that it is because i am usinng 97 main caps on an 02 1mzfe block.... it is the mains though, not the rod bearings... would the difference in caps cause it to do that?

***JohnGD*** · 08-26-2009, 08:23 PM

Sure. You have to get the correct oil clearance. If you go the other way and got them too loose, then you'll have too low an oil pressure!

Usually you turn them by hand to check before doing the work of putting pistons on there.

Quote:

Originally Posted by ekopel

ok so after talking to my mechanic and plastigaging everything, it turns out i dont have enough bearing oil clearance. im thinking it is either because my crank was not correctly machined, or that it is because i am usinng 97 main caps on an 02 1mzfe block.... it is the mains though, not the rod bearings... would the difference in caps cause it to do that?

***JohnGD*** · 08-26-2009, 08:33 PM

Also, how's the condition of the head bolt threads? Did you have to chase the threads?

The newer 2.4L engines have problems with the head bolt threads disintegrating, and the cylinder head pops up leaking ooolant. So I wonder how the old aluminum block is holding up.

ekopel · 08-27-2009, 03:38 PM

new head bolts...