outpostm37 wrote:Thanks for the flywheel info. My M37 is a 1963. When the engine did run, it seemed very smooth. Never had any issue with the starter disengaging from the flywheel. Anyone know if these engines were balanced with the crank and flywheel bolted together? I plan on using this flywheel again, I have had it resurfaced, and plan to have it balanced. Any benefit of having the flywheel/clutch assembly bolted together when balancing? The odometer read 64,000 miles. The engine had .030" over size pistons in it. Mysteries abound with this creature.
That flywheel looks like the thinner, six-bolt civilian flywheel that was in my M37 when I bought it. Someone had swapped it in to go with the 12v civilian starter.
I don't believe that the factory balanced the crankshafts on these engines (I've not seen any evidence of balancing holes in the counterweights of the crankshafts I've looked at). Having weighed about thirty different 230ci connecting rods to find six relatively close ones, I can say from experience that the factory tolerance on balanced rotating/reciprocating weight was rather large.
These engines are internally balanced (i.e. they do not have an external balancer on the end of the crankshaft), so ideally the flywheel and clutch pressure plate assembly would be zero balanced separately, and then the crankshaft would be balanced by itself. However, these are not high RPM, high-stressed engines, and the crankshafts are not known weak points, so balancing the crankshaft with the flywheel and pressure plate assembly attached should not be a problem. That's how I had mine balanced.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
outpostm37 wrote:Thanks for the flywheel info. My M37 is a 1963. When the engine did run, it seemed very smooth. Never had any issue with the starter disengaging from the flywheel. Anyone know if these engines were balanced with the crank and flywheel bolted together? I plan on using this flywheel again, I have had it resurfaced, and plan to have it balanced. Any benefit of having the flywheel/clutch assembly bolted together when balancing? The odometer read 64,000 miles. The engine had .030" over size pistons in it. Mysteries abound with this creature.
That flywheel looks like the thinner, six-bolt civilian flywheel that was in my M37 when I bought it. Someone had swapped it in to go with the 12v civilian starter.
I don't believe that the factory balanced the crankshafts on these engines (I've not seen any evidence of balancing holes in the counterweights of the crankshafts I've looked at). Having weighed about thirty different 230ci connecting rods to find six relatively close ones, I can say from experience that the factory tolerance on balanced rotating/reciprocating weight was rather large.
These engines are internally balanced (i.e. they do not have an external balancer on the end of the crankshaft), so ideally the flywheel and clutch pressure plate assembly would be zero balanced separately, and then the crankshaft would be balanced by itself. However, these are not high RPM, high-stressed engines, and the crankshafts are not known weak points, so balancing the crankshaft with the flywheel and pressure plate assembly attached should not be a problem. That's how I had mine balanced.
I have seen videos of the factory balancing the crankshafts. maybe they removed material another by shaving counter weights? the video didnt show them removing material was just a quick shot of a guy running them on the balancing machine. they wouldnt run as smooth as they do without it i dont think.
Kaegi wrote:I have seen videos of the factory balancing the crankshafts. maybe they removed material another by shaving counter weights? the video didnt show them removing material was just a quick shot of a guy running them on the balancing machine. they wouldnt run as smooth as they do without it i dont think.
I'd very much like to see that video! Do you recall where you saw it?
There are some notches in the counterweights of these cranks, but they seem unlikely to be for balancing. I figured they had something to do with the original machining process.
As I posted above, there's a lot of variance in the weights of the connecting rods, so the factory wasn't too precise on the balancing. Chrysler is, after all, the company that invented cushioned engine mounts and the "floating power" system, all to isolate engine vibrations from the rest of the vehicle. Perhaps that was easier and cheaper than balancing hundreds of thousands of flatheads every year, given the state of machining technology at the time.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
Kaegi wrote:I have seen videos of the factory balancing the crankshafts. maybe they removed material another by shaving counter weights? the video didnt show them removing material was just a quick shot of a guy running them on the balancing machine. they wouldnt run as smooth as they do without it i dont think.
I'd very much like to see that video! Do you recall where you saw it?
There are some notches in the counterweights of these cranks, but they seem unlikely to be for balancing. I figured they had something to do with the original machining process.
As I posted above, there's a lot of variance in the weights of the connecting rods, so the factory wasn't too precise on the balancing. Chrysler is, after all, the company that invented cushioned engine mounts and the "floating power" system, all to isolate engine vibrations from the rest of the vehicle. Perhaps that was easier and cheaper than balancing hundreds of thousands of flatheads every year, given the state of machining technology at the time.
no dont remember which video. in another 30s chrysler video they were balancing other parts on super sensitive machines. one was so sensitive that when the stuck a piece of confetti on the part and spun it, the machine picked it up. I wouldn't underestimate the balancing capabilities of the time. I have had NOS Chrysler pistons balanced and they were very close according to the balancer. more important than the rods I think. these engines rarely even see 5k rpms anyway. the idle spec on a straight 8 is 325. try doing that with modern engines. they might do it but it wont be smooth. ;/)
Kaegi wrote:I have seen videos of the factory balancing the crankshafts. maybe they removed material another by shaving counter weights? the video didnt show them removing material was just a quick shot of a guy running them on the balancing machine. they wouldnt run as smooth as they do without it i dont think.
I'd very much like to see that video! Do you recall where you saw it?
There are some notches in the counterweights of these cranks, but they seem unlikely to be for balancing. I figured they had something to do with the original machining process.
As I posted above, there's a lot of variance in the weights of the connecting rods, so the factory wasn't too precise on the balancing. Chrysler is, after all, the company that invented cushioned engine mounts and the "floating power" system, all to isolate engine vibrations from the rest of the vehicle. Perhaps that was easier and cheaper than balancing hundreds of thousands of flatheads every year, given the state of machining technology at the time.
no dont remember which video. in another 30s chrysler video they were balancing other parts on super sensitive machines. one was so sensitive that when the stuck a piece of confetti on the part and spun it, the machine picked it up. I wouldn't underestimate the balancing capabilities of the time. I have had NOS Chrysler pistons balanced and they were very close according to the balancer. more important than the rods I think. these engines rarely even see 5k rpms anyway. the idle spec on a straight 8 is 325. try doing that with modern engines. they might do it but it wont be smooth. ;/)
This might be one of the videos you mentioned: https://www.youtube.com/watch?v=2SBNoik ... gs=pl%2Cwn. Starts at the 16:14 mark. It doesn't specifically describe balancing of production engines, only that the balancing of a crankshaft shown in the engineering lab has benefited production automobiles.
As for pistons, the variance of the NOS Chrysler 230 0.040" oversized pistons I used weren't too bad, but they did require some material removal to get them matched up.
“When a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, IT IS THEIR RIGHT, IT IS THEIR DUTY, TO THROW OFF SUCH GOVERNMENT...” -Declaration of Independence, 1776
The cranks in both of my engines have balancing holes drilled in the cheeks. I had one checked when we rebuilt it and it didn't require much to get it balanced. The rods were another story! Elwood came to the rescue . The pistons (NOS from the early '70's) were good out of the box. If you're rebuilding and looking for some easy power and economy raise the compression ratio! We're at 8:1 static and run 87 octane. It was well worth the effort. We picked up a bunch of torque and 3+MPG.
Andy
Last edited by ashyers on Sat Feb 09, 2019 7:36 am, edited 1 time in total.
no thats not the video but that is a good one. chrysler developed so many things still in use. there is a good segment in that one on oilite bushings they invented.
More learning going on here.
Saw some cam bearing relief notching on the 230 engine I purchased (top jpg) . Thought this seemed odd. Talked with several folks that were familiar/rebuilders/parts sellers of these engines about what I saw. "Sounds like someone did some shade tree work" Well the new Federal mogul cam bearings showed up today. Shocker, two of the cam bearings have the relieve sections on the bearing sides. Bottom jpg is the new Federal Mogul cam bearings with factory FM clearancing on the sides of two of them.
Attachments
tappet and cam bearing (4).jpg (89.84 KiB) Viewed 2807 times
new FM cam bearings (3).jpg (66.91 KiB) Viewed 2807 times
I gave a tappet to the machine shop that is replacing the cam bearings. Showed them what the concern was. The machine shop has "old school" guys working there. They had a 230 flat head 6 cylinder from a 1948 Chrysler in the shop at the time. Should be no issues.
Friday I received the 230 crankshaft, civi flywheel, and new clutch pressure plate back after machining/balancing.
Posted is the jpg of the results before and after on rotational balancing on the Sunnen DCB 750 balancing machine. Mallory metal was used for added weight on the counter weights.
The civi flywheel is the one that was on the engine when I received it. So I resurfaced it and used it for the balancing operation, it will be used on the vehicle. The crankshaft journals cleaned up with a .010"/.010" cutting.
More to come when the block is decked, and bored .030" over.
Attachments
230 flat head 6 crank balancing (1).jpg (95.83 KiB) Viewed 2721 times
Visited my local machine shop today. The cylinder boring was in process. Looks like I will need to go to .060" for a clean cylinder surface.
Pics are:
.048" rough bore (headed to .060" looks like they are cleaning up ok)
The first cut was at .025" rough bore (lots of water pitting in the walls)
After the bore/hone, the deck will be machined to get rid of the water pitting.
Attachments
230 engine rough bore to .048%22 (1).jpg (57.54 KiB) Viewed 2696 times
230 flat head at .025%22 over bore (1).jpg (69.54 KiB) Viewed 2696 times
Home 
. The pistons (NOS from the early '70's) were good out of the box. If you're rebuilding and looking for some easy power and economy raise the compression ratio! We're at 8:1 static and run 87 octane. It was well worth the effort. We picked up a bunch of torque and 3+MPG.
Better pay close attention when putting those in.