ok i got one for the engine guru guys.rebuilt my engine,set everything to factory specs(torque wise)or so i thought!turns out my buddies torque wrench was out of calibration to the point that the starter would not turn the motor!i got another wrench reset all the bolts(worst ones were the rod bearing bolts).i went to fire the motor,everything was turning fine(but never fired)and slowly the motor started dragging,slower and slower to the point it would not turn no more! removed the oil pan,and low and behold,the rod bolts ended up tightening themselves back up tight again is it safe to say that i toasted my main and rod bearings? by the way the main/rod bearings are stock replacements.bearings had no groovs or wear on them.engine is a 302.please help,i want to go cruising! thanks in advance and any help/suggestions is appreciated,chuck.
You say you rebuilt the motor. What exactly did that entail? I will go out on a limb here (pretty sturdy limb) and say rod bolts cannot tighten themselves up, especially by turning it over with the starter. Did you have the crank turned? If not, has it ever been turned and if so or not, did you put the right bearings (standard or oversize) in it? How about piston rings? Was the block bored? If so or if not, is the correct rings installed? Did you set the ring gap? Are you just spinning the bottom half or is the valve train hooked up?
crank wasn't turned,whole engine only had 32k miles,just sat awhile.standard bearings,new rings,everything standard.end gap was checked.valve train is all hooked up.got me stumped.
Check to make sure the rods are oriented correctly and they are in the correct bank. The rod bearings are slightly offset when placed in the rod and the rod has a chamfer on one side. The chanfer side should be to the radius in the crank journal. The square (non chanfered sides) of the rods go back to back to each other on opposing cylinder banks. You can physically install rods backwards like this and it will look right but it will be hard as he$$ to turn over because the non chamferd side of the bearing digs into the crank radius. Cleaver
thanks cleaver,the rods are all in their correct bank,and installed correctly.is it possible i killed the main and rod bearings when i way over torqued?
Thats a bummer, man. Im guessing you didnt rotate the engine during re-assembly... good habit to get in. Also, did you pre-lube the engine, or use any engine assembly lube? Were the new bearings plasti-gauged? Gonna have to tear her down and inspect it, buddy.
How much over torqued do you think they were overtorqued? 302 rods are about 35 ft-lbs, right? If you got the pan off, go ahead and pull off one cap and look at the wear pattern. If you overtorqued more than (this is a guess) 20ft lbs on the rods I am more worried about the bolts being stretched to far more than the bearings. Bearings are designed to crush a few thousandths and then the cap bottoms on the rod. Then the torque on the fastener basically created a stretched spring effect to hold it all together. I'ts hard for me to imagine the bolts being so tight that they would be killed. The whole cap would have to be distorting. I guess its possible - (not an expert here - just learned some things by hard knocks). Did the engine fire and did you have oil pressure? If automatic transmisison did the converter seat all the way? Cleaver
overtorqued to at least 50-55 pulled 2 different bearings,no marring or grooves.i got the engine to fire,ran for about a minute,75lbs.pressure.torque converter is a b/m and was seated all the way.one thing i did notice,is that when it finally decides to turn over you can hear a whine/hum coming from the selonoid,like it's under a heavy load,then when it's had enough,it just clicks,like the battery is dead,but it isn't.
Hmm... have you tried pulling the starter back out and turning it with a breaker bar? I had a starter go bad just after putting the engine back in my car. Made the engine feel like it was locked up.
jamie,i haven't tried that yet.i pulled all the plugs out and it cranks over fine,like a brand new car.i put the plugs back in,and it,how do i say it,it drags.i'm starting to lean towards the starter.i pulled the battery out of my truck,which i know is good,and the same thing happens.also when i hit the key with the plugs in,you can hear a hum/whine coming from the selonoid on the fenderwell.thank you,for the suggestion.
I'd replace the starter & the solenoid (just to be safe). I had that same drag once in awhile on my 302. I replaced the solenoid, still did it some times. Then went out to start one day & click! I had just put in a new battery also. I replaced the starter & it fixed the problem....Good luck! Hope it fixes it...
a better Torque Wrench is what you need http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00944595000
If this 302 has stock rod bolts, I don't see how they would make 50-55ft-lbs. without breaking/stripping. They are 5/16" and torque to a max of 25 ft-lbs. I have a buddy who drag races a low 12 second '83 Mustang with a 302. A couple of years ago he decided to build a new engine(it had stock bolts in it) and torqued them to 38 ft-lbs. Someone told him that was the correct torque(I think they thought he had ARP bolts in it). Anyway the first time he took it down the road and run it through the gears, it slung one or more rods out of it.
