Amata Bene
Well-Known Member
So, I have been mulling this over for a minute. I picked up my block and crank from the machine shop a while back. Checked the work, coated it with WD, and bagged it. In the meantime, I worked on porting the J-heads, disassembling the 904, cleaning and inspecting, along with gathering the remaining parts for reassembly of the motor and trans. Not to mention working on the jobs that come into my shop. The whole while with a nagging statement in the back of my mind, “That’s not how they do it.”
As I have said in other posts in this and fellow forums, I am not an engine builder, a mechanic, a transmission guy, or anything that resembles these. I have always been good with a wrench and building things. Which at best makes me a good shade-tree grease monkey that has had some success. Couple hot rods when I was younger, some bikes through the years and to present and Jeeps. My forte for the last 40 years or so has been steel, lots, and lots of steel. I own and operate my own small welding repair shop now. It keeps me busy and helps me think I’m contributing to the family budget. My wife and I both know the truth though, LOL. I play a lot more than I earn. Good thing we made our money early. The health care and steel industry set us up and we are blessed. Glory be to God.
I digress, back to that nagging statement, “That’s not how they do it.” This statement was made when I was picking up my finished 340 block and crank from the machine shop. When I dropped off the block with the crank and rods, I also left an unopened box of KB243.040 slugs, pins, and locks with instructions to replace the mains and rod caps with ARP hardware and balance the rotating assembly. While waiting for the rod bolts to arrive they called and asked if I wanted them to assemble the rods and pistons. I said sure it’s one (8) less thing for me to assemble. I was paying the balance on my bill and asked how they marked the rod and piston combo for me to know what hole they go in. The woman at the counter said they still have the stampings that I marked them with. Confused, I replied, wouldn’t they move rods around while doing the balancing to match up heavy rods with light pistons and what not. She says “That’s not how they do it. They weigh one rod, one piston, one set of rings, one pin, and one set of locks and then balance the crank to that.” Confused and not going full steelworker on her, I collected my receipt, went out to my truck, checked the straps, climbed in, and pointed it towards home. With more than 50 miles to go I had plenty of time to ponder this. I made a couple phone calls and confirmed I wasn’t completely crazy. To their defense the work performed is spot on, well within all tolerances. Actually, really good. Just the whole balance thing.
I am not building a race engine (right now). This is only going to be a well performing street engine that will see some hard hits showing off and the occasional rip down the track. One of the fellas I talk with is an automotive machinist with his own shop and a very impressive pedigree. He is slammed with work, always is. 3 month waiting list minimum. He told me to buy a good scale and see what I get weighing each assembly. Well about $160 later and I have my scale. It is very sensitive. Might be a bit much for auto parts iiwii. Just can’t exhale on it while in use lol.
Had the time today to weigh each rod & piston combo. The list is below. I will talk with “Joe” about the results but that will be on his schedule so it could be several days. In the meantime have a look and I’m open to easy fixes. This is according to how the engine came apart with the stamping on the rods and caps.
As I have said in other posts in this and fellow forums, I am not an engine builder, a mechanic, a transmission guy, or anything that resembles these. I have always been good with a wrench and building things. Which at best makes me a good shade-tree grease monkey that has had some success. Couple hot rods when I was younger, some bikes through the years and to present and Jeeps. My forte for the last 40 years or so has been steel, lots, and lots of steel. I own and operate my own small welding repair shop now. It keeps me busy and helps me think I’m contributing to the family budget. My wife and I both know the truth though, LOL. I play a lot more than I earn. Good thing we made our money early. The health care and steel industry set us up and we are blessed. Glory be to God.
I digress, back to that nagging statement, “That’s not how they do it.” This statement was made when I was picking up my finished 340 block and crank from the machine shop. When I dropped off the block with the crank and rods, I also left an unopened box of KB243.040 slugs, pins, and locks with instructions to replace the mains and rod caps with ARP hardware and balance the rotating assembly. While waiting for the rod bolts to arrive they called and asked if I wanted them to assemble the rods and pistons. I said sure it’s one (8) less thing for me to assemble. I was paying the balance on my bill and asked how they marked the rod and piston combo for me to know what hole they go in. The woman at the counter said they still have the stampings that I marked them with. Confused, I replied, wouldn’t they move rods around while doing the balancing to match up heavy rods with light pistons and what not. She says “That’s not how they do it. They weigh one rod, one piston, one set of rings, one pin, and one set of locks and then balance the crank to that.” Confused and not going full steelworker on her, I collected my receipt, went out to my truck, checked the straps, climbed in, and pointed it towards home. With more than 50 miles to go I had plenty of time to ponder this. I made a couple phone calls and confirmed I wasn’t completely crazy. To their defense the work performed is spot on, well within all tolerances. Actually, really good. Just the whole balance thing.
I am not building a race engine (right now). This is only going to be a well performing street engine that will see some hard hits showing off and the occasional rip down the track. One of the fellas I talk with is an automotive machinist with his own shop and a very impressive pedigree. He is slammed with work, always is. 3 month waiting list minimum. He told me to buy a good scale and see what I get weighing each assembly. Well about $160 later and I have my scale. It is very sensitive. Might be a bit much for auto parts iiwii. Just can’t exhale on it while in use lol.
Had the time today to weigh each rod & piston combo. The list is below. I will talk with “Joe” about the results but that will be on his schedule so it could be several days. In the meantime have a look and I’m open to easy fixes. This is according to how the engine came apart with the stamping on the rods and caps.
- 1477.72
- 1485.67
- 1483.17
- 1481.77
- 1479.09
- 1477.82
- 1483.02
- 1489.76















