The cat book says for rods to torque to 30 ft lbs and then turn another 90°. Is there any literature anywhere that has just a straight torque wrench method ? Just seems like an odd way to do rods and mains.
It’s actually a more accurate way than a straight torque method because it pretty much takes any variable friction factor in the threaded fastener out of the equation. Tighten them the way the book says and forget about them. Torque-turn is used on all critical fasteners these days.
Reason I ask is i had a couple that just didnt feel right. I checked with my torque wrench and found they were not equal on the torque. Had one the second nut seemed way to easy and it was not equall in torque. Anyhow i backed it off and started over. Second time it felt like they pulled equal. After taking a shower and having some dinner i got to thinking about it and wonder if it all was not seated correctly. Wondering if i should break them all loose and re tourqe a second time now that its all seated. Also I ordered one of them fancy indicators that has a degree wheel so you can measure the turn.
I kept a set of used rod bolts and nuts for any trial fitting and used new ones for final assy. With used ones on old engines like those, you have no way of knowing if they have been torqued beyond their elasticity limit during previous repairs or if they are the original bolts. A lot of newer torque-turn(stretch) bolts are one-time-use only. New rod bolts are cheap compared to a hole in the block
Also, after the initial torque, i mark them all with a line in one direction so i can tell where i started and also if i have missed any. After the 90 degrees( or whatever) when you’re done them all, the lines on the bolt heads should be all facing the same direction.
I had been into a lot of engines before I worked on any Torque-turn stuff. I didn't like it but I went by the book and had great luck .
I was going to ask @workshoprat92 if he used new hardware or not, because what he experienced should not happen using new fasteners. TBH any critical fasteners such as those if I had no idea of the provenance of the old ones then they would be junked and new ones installed.
I checked and cat want around $22 per bolt! Ouch. Still like you say cheaper than a hole in the block. The hole thing has me worried and i am going to order new ones today. I like your idea of using the old ones to do an intial set. Then probaly replace them with new one at a time.
I agree with this and at this point im not willing to take a chance on them. Cat bolts are pretty expensive. I can get aftermarket for about 1/4th the cost. Are they worth it or just bite the bullet and get genuine cat? The aftermarket ones are CTP brand.
I've only ever had experience with OEM hardware in this situation so I couldn't say one way or the other.
I've never had issues with aftermarket head, rod or main bolts. I use PAI normally. Normally can measure for stretch. IMO if a head bolt can't be used at least twice it's a great marketing ploy. They make torque turn for old cummins too--I won't use them. These companies are making mass amounts of money off one time use fasteners. Like most things these days--the cool aid is selling well. * Case in point-the BC 400 I just built the first set of head bolts I ordered standard by part number, turned out when opened box--torque turns at $425.00-I returned those and the correct original head bolts were sent $200.00 for 36 instead of one time use torque/turns at $425.00. And I unfortunately had to tear this last engine down to reinspect---what $850 for head bolts that's total bull ****, no one likes a redo for integrity conformation but it happens. This idea each bolt is exactly torqued like it's corresponding mate is manure also--these engines are not rocket stuff--it's why there is a plus/minus on final torque values.