HEy, since ive got the oil pan off...I want to make sure the rod end bolts and the main caps are TQ'd to specs. Does anyone know the specs? my rod bolts are ARP and the main cap bolts look to be something other than ARP.
How do I got about doing that? do I break the TQ and then re-TQ them ...or just TQ them to what they are suppose to be?

Also, I dont know much about the bottom end but what about the clearance on the side to side motion on the rod ends on the crank? anyone know whats suppose to be within spec? I know it has to do with the engine biulder and how it was built but I dont know anything about that.

I can move them from side to side when they are in the down position but up top they are tight...nothing moved up and down...just side to side.

thanks!

 

rod bolts aren't torqued they're set to a certain bolt stretch. main caps are shown on the ARP website for tq values, assuming your machine shop used a certain torque value to set bearing clearances.

 

The correct torque values depend on which bolts you have, and what lubricant you use on the threads. You may as well just leave them alone, though. If they were torqued incorrectly, the engine would have eaten itself by now.

Rod side clearance should be somewhere around .008"-.015" or so. If there's less, it's bad. If there's more, don't worry too much about it because there's not a lot you can do about it anyway.

 

ok..i used a feeler gauge and came up with .020 between the rod ends....
ok about the rod bolts...I'll just leave them..

what about the main caps?

 

I'd be just as inclined to leave them alone, too. You can't fix what's not broken.

 

ok..cool!......so your saying that if anything was loose or out of spec...the motor would have chewed itself by now?
I found no metal whatsover in the oil or the pan when I took it all apart.

how do them bolts not come loose under all that stress and torque?

 

Why would they come loose?

 

Friction.

 

why do all other bolts on the motor come loose? what makes them bolt so special not to?

 

A properly torqued bolt doesn't loosen.

 

Gasketed joints have a lot to do with fasteners that loosen.

 

If they were torqued correctly to begin with, I'd leave them alone.

 

Exactly. When you have two metal surfaces (like a main bearing cap and block ) you can tighten it up REALLY tight, and get bolt stretch. That holds it in place. But if you're tightening onto a cork or rubber gasket, you aren't stretching the bolt, you're only compressing the gasket a tad. That is easier to loosen up, if it's subjected to a lot of vibration. The oil pan wouldn't vibrate much, but the headers, with the whole length of exhaust hanging down, shaking at will, that's more prone to loosening the bolts.