Rebuild Question

[johnstra]

Hi mates. I'm rebuilding my 1kzte and I have a question. With no pistons installed, the crank rotates freely on the mains. When I installed my pistons, there is a fair amount of resistence when turning the crank over (the head is off). I know the pistons are oriented correctly and the conrod caps are correct. There's no sound and no real indication of binding. I just thought the assembly would rotate easier.

Does this sound normal? Is it just side-loading on the pistons at mid-stroke?

Thanks for any insight.

-john

[surfenstein]

have you used plastigauge,to make sure the bearings are all seating correctly and arent binding.that would be my first port of call,then the obvious make sure every thing is spotlessly clean no grime.oil everything up on re build.

[johnstra]

Yes, I used plastigage to verify bearing clearances. All was good.

Everything is spotless and everything was oiled when reassembled. I'm not convinced there is a problem, but I'm not entirely comfortable with how tight it feels when rotating the crank.

I know this is damn near impossible over the internet, but does anyone have any guidance for how tight the assembly should feel? With the harmonic balancer on the crank, I can turn it over with my hands but it's not easy. I have to apply a fair bit of muscle to get it to go. Without the balancer, I cannot turn it over with just my hands on the crank.

The cylinders are bored .5mm over and honed, I have new .5mm over pistons and rings. The cylinder walls look perfect, so it's not a ring snagging the bore.

-john

[surfenstein]

that sounds about right to me,dont forget you have an extra set of compression rings compared to a petrol motor so it will feel a bit tighter.