KA Rebuild help

[GO240]

ok i've put my crankshaft back in and bolted the cradle down and the pistons and rods are to now i'm wondering why it won't turn over at all i havent assembled anything else because this is worrying me is this normal???

[slipnfall]

'Need a little more detail - what work was done prior to re-assy? Did you check to ensure the rod end caps are in their proper places? Will the crank rotate by itself?

How much effort are you using to try and turn it over?

[Vegascorbin]

You did lube the bearings before you put things together didn't you? If not then even if you get it ot turn you will ruin your bearings before you even get started.

[GO240]

Ok the motor was supposedly rebuilt i just tore it down to clean a timing chain guide out of the block all the bearings where still in good condition and it spun just fine before we removed but now it won't turn at all only when its just siting in the block will it turn and I lubed everything

[del82]

Ok the motor was supposedly rebuilt i just tore it down to clean a timing chain guide out of the block all the bearings where still in good condition and it spun just fine before we removed but now it won't turn at all only when its just siting in the block will it turn and I lubed everything

Sounds to me like you didn't label your bearings to which journal they went to during teardown, and probably didn't use any assembly lube while putting it back together?

If you're re-using bearings, they have to go back in the same place they came, they don't usually wear evenly, and its based on the ...well, lets just label em engine harmonics to save a long explanation of how vibration works in an engine.

So, if you're already past that point (looks like you are), its time to buy some new bearings, and tear it all down again. Only this time, you may as well send the bits off to the machine shop to be honed. Ask them for their opinion on the crank and main journals on the block, and what grind undersize you will need, or if it'll just be a hone. When you reassemble, dry assemble it first, using plastigauge to check clearances, then for the wet assembly, don't forget to use PLENTY of assembly lube. After you get it all running again, let it run for around 15 minutes, then change the oil and filter, to flush out all the assembly lube.

Keep in mind none of this is special procedure. Really, if you plan to fully disassemble the engine, you may as well at least hone it and put in new bearings before you put it back together. Most smaller engines can be rotated by hand until the cylinder heads are put on, if you need a point of reference on how hard it should be to turn. If you're feeling/hearing grinding, or you need a wrench and a few expletives to turn it, you probably didn't grease things properly on the way in.

[Vegascorbin]

Be aware that some assembly lube is for cams and slightly abrasive. We just used good old STP and it worked fine.

[GO240]

i never took the bearings off the rods and crank i just left them as they where i'll go back with some good old fashioned 10w40 and re lube all the bearings and i can't find the number on the rod to designate which piston it is i just know which one is 1 and 4 and which one is 2 and 3 but then i don't know which one is which from those two