Connecting Rod Orientation
 

I have a question that I hope someone can help with. I have a 2001 SL1, with the 1.9, SOHC engine. The car has 206,000 miles on it and this if the first real problem I've had with the car. It's been a great knock around car up till now.

So when the timing chain guide broke into a thousand little pieces and the timing chain slipped a tooth or two, and then broke the no. 1 and no 2 exhaust valve rocker arms, and broke the no. 3 exhaust valve off mid stem, I figured it's time to rebuild the engine. So I've taken the engine out, stripped the engine down to the bare block. Had a machine shop check the engine and clean it. Honed the cylinders but did not have to bore. I have a rebuild cylinder head, new pistons, now rod bearings, and new crankshaft bearings, and of course a timing chain set.

So I set off to start reassembly. I had laid out the removed piston and rod assemblies in the order that they were removed so that I could put the rods back into the same positions that they came out of. But here's where I made my mistake. I initially looked at the rods and didn't see a difference between the front and the back sides - until I had transferred them to the new pistons and had the pistons loaded back into the block. That's when I noticed that down where the rod connects to the crankshaft, there is a difference between the tow sides, right where the rod cap and the rod mate together. One side is machined out to the outer edge of the rod/cap and the other side has a more rounded and recessed machined area. So I'm guessing there is a reason for this difference.

Does anyone know why the two sides are different and more importantly, does anyone know which side should be facing toward the front of the engine? :confused:

Wish I could help, man. But I never got into any of the engines of the ones that I've owned. Are they stamped with numbers? I always stamped mine before taking them apart. But that was 99% Mopar engines back in the days of my youth.

Well after extensive search of pics on the internet, I believe I found my answer. Rockauto and GearHead web sites both have a set of photos of this engine from all 6 sides including the bottom and from that picture I was able to see the orientation of the connecting rods. Surprisingly, I got mine installed the correct way. The recess rounded side toward the timing chain (front) and the squared off side that comes out to the edge of the rod and cap toward the transmission (rear). Oh happy me!!!

Happy to hear you got it right the first time. Sure would have been a pain in the ass to remove the pistons from the cylinders, take them loose from the rods and then turn them all in the other direction. Fire that sum beech up and let us know how it runs.

I think he needs to reattach the head first...

You know what I mean, derf. Stop being a turd! :D

Well now that I'm OK with the rod orientation (and it's warmer than 15 degrees in my garage) the head will go on this weekend along with the timing set, oil screen, oil pan, starter, alternator, rear seal, flex plate, and all the sensors and hopefully drop it back into the engine bay. Although I do have to pull out the heater core and get the new core and new heater pipe in before dropping the engine in while is I still have wonderful access to the heater core nipples coming through the firewall.

I'll take some pictures as i progress and post them even though I already have the crankshaft and pistons and rods installed. You can decide if you want to create a sticky with them. Hopefully they will help someone else down the way with pics of the engine going back together.

Pics from a shot block assembly are better than no pics at all. There are videos on what you've already done all over youtube is someone needs them.