How long may a freshly rebuilt engine sit without running?
 

GSR Head & Block fresh from machine shop, with forged pistons & rods going turbo. Probably won't be able to throw it back together and get it running before winter, but I have plenty of time over winter to finish my project. How long could the engine stay assembled before firing & stay properly lubricated so that nothing would rust or gunk up?

Re: How long may a freshly rebuilt engine sit without running?
 

I had my short block (rotating assembly all put together too) wrapped in plastic wrap for almost two years until the complete motor was assembled. No issues.

Re: How long may a freshly rebuilt engine sit without running?
 

Re: How long may a freshly rebuilt engine sit without running?
 

I saw a motor wrapped and sat for 20 years. We pulled the heads and went crap this is a fresh rebuild. Squirted some oil and manually spun the crank. It was good to go

Re: How long may a freshly rebuilt engine sit without running?
 

Yep. You'll be completely fine as long as you keep the engine wrapped up and somewhere out of the rain. If you're spinning it over by hand make sure you have oil in it, I'd actually just wait until you're ready to do the install, and put the oil in and turn it over a couple times by hand before building oil pressure via the starter.

Doesn't really matter though. I've had engines sitting around for way longer than that, in worse storage, with no problems after the oil is primed.

Re: How long may a freshly rebuilt engine sit without running?
 

I was under the impression the assembly lube was to take place of the oil until the engine primed itself. It's some thick stuff. Is it not to allow you to turn the motor without oil safely?

Re: How long may a freshly rebuilt engine sit without running?
 

I would say keep it lubed up with assembly oil and leave it be, no need to continually turn it over and move that assembly oil around

Re: How long may a freshly rebuilt engine sit without running?
 

You can turn it over, but I'm unsure how long you can leave the assembly lube in there if the engine sits for months; my concern would be the lube sinking or running away from the metal it's supposed to be protecting, especially if the engine is being turned over periodically. Over time the lube may get worn away (speculation, I have no idea on the actual longevity of the lube).

I don't have an entirely straight answer; my best idea would just be to leave the engine alone until it was ready for installation.

Re: How long may a freshly rebuilt engine sit without running?
 

Just make sure it's wrapped in a large bag to keep elements out. Those "lawn" trash bags should do the trick. They make them in clear instead of black.

Re: How long may a freshly rebuilt engine sit without running?
 

Sounds like, the lube is fine for ages, just don't repeatedly rotate the engine after engine has been assembled and tested (rotated by hand to verify operation).