icemang17 wrote:Mulry wrote:I'm fixing to get my crankshaft back from the machine shop that polished out all the damage we did to it when we blew our motor back at Yee Haw It's Lemons/Houston Fall 2009. I've fully disassembled the motor, cleaned up what needed to be cleaned up, scraped what could be scraped, and I'm going to soon be assembling the motor.
This will be the first time I've ever fully assembled a motor from start to finish.
I'm looking forward to the challenge, but I'd be lying if I didn't say that I'm a little intimidated by the process too. I've got the Toyota factory manual for my 4AGE and I read through it pretty thoroughly when I was doing the dis-assembly, so I think I have some idea what I'm getting myself into in putting it back together. Ha! Yeah, I'm self-delusional, too.
So, I want to get this motor back together such that it will run a couple races before it blows up again. Are there any great secrets that y'all are willing to share regarding getting it right other than to follow the instructions meticulously, use assembly lube, and keep everything clean? I'm just a little lost lamb here looking for a way out of the woods. Cheers.
Granted I'm no engine builder (its much easier picking them up at junkyards)....but the guys that build the hot rod big $$$ porsche engines all use the assembly lube (redline is popular) & quite a bit of it.....they also MEASURE main and rod bearings....plastigauge will work...just make sure your bearings are within spec for your motor....tighter IS NOT better.....in fact you want to be in the middle-loose end of the range....for example 928 rod bearings are spec'd from 19 to 35 thousandths.... I have yet to find a 928 engine builder who builds an engine tighter than 25 thousandths......
Just take your time and measure everything & you should be fine....break in oil with lots of ZDDP helps too.......I am breaking in a 5.0L 500+ HP 928 engine tomorrow!!!! Double the power of the estate in a car that weighs the same!!
Hey Dick! i think you are trying to say 1.9 to 3.5 thousandths because if they are built at 19 or 35 thousandths you would have a spun bearing in about 10 minutes.
Simple rule of thumb. 1.0 to 1.5 thou for street motors big blocks don't count on that one you want 2.5 to 3.0 or they will seize a bearing. Now race motors it depends on cast iron block or alloy and on alloy it depends if it is a high silicon block with alloy bores or a alloy block with steel sleeves.
On a Lemons race motor! Put rods at 2.0 and mains at 3.0 to 3.5 use a good oil and let it rip.
Use caution on shimming the oil pumps to much because it can cause the pump drive to break or the gear to chatter and deliver it's guts into your engine.
Pimp-de-jo
