[moroeder]

I'm trying to determine when a crank should be polished or re-ground. Can you use standard mics to do a simple measurement and accept all the area under the mic anvil(s) as being the same or what? It's hard to use a test indicator while the crank is still in the engine so what is suggested, please.

[hcompton]

Originally Posted by moroeder

I'm trying to determine when a crank should be polished or re-ground. Can you use standard mics to do a simple measurement and accept all the area under the mic anvil(s) as being the same or what? It's hard to use a test indicator while the crank is still in the engine so what is suggested, please.

Is it showing wear scratched or lines running around the journals. Then it needs to be cut. Almost certainly. Be sure to check the price of a new eagle or scat crank. Sometimes they are cheaper than getting an old one polished. Or at least close and makes the new crank price worth the money.

Usally need pointed mics to guess but to be sure you have to cut it and see how much it takes to remove the damage.

If it has light surface rust then a quick polish can restore the smooth surface but if its pitted the damage must be cut out.

[moroeder]

Forgot to identify crank condition. Engine was running well and dropped a seat. Cylinders were marginal so I pulled the rods to see almost the same pattern on the bearings as what someone posted a pic calling it a "Ohio" crank. My wear if wear at all in the bearings shows those lines but you can take a piece of writing paper and lightly rub the lines out to a slight dull buff appearance. Crank looks good but isn't new, not going into a racer, mics good but you can see light phantom lines in the surface. The phantom lines are polished with no obvious damage. The "ohio" look on the bearing faces concerned me the most.

[hcompton]

Originally Posted by moroeder

Forgot to identify crank condition. Engine was running well and dropped a seat. Cylinders were marginal so I pulled the rods to see almost the same pattern on the bearings as what someone posted a pic calling it a "Ohio" crank. My wear if wear at all in the bearings shows those lines but you can take a piece of writing paper and lightly rub the lines out to a slight dull buff appearance. Crank looks good but isn't new, not going into a racer, mics good but you can see light phantom lines in the surface. The phantom lines are polished with no obvious damage. The "ohio" look on the bearing faces concerned me the most.

If the crank is clean and shows no damage just run it if you see marks on the crank then it will need to be polished or turned. Usally its all the same price.

Bearing where is no issue usally that is what they are supposed to do. If cylinders are worn then the bearings should be pretty much gone as well.

Now does the crank show damage going around the pin? Or the bearings have dqmage that appears to go around the entire pin. Usally if something like that happend its needs to go the the shop. Or spun bearing. If the top and bottom of the bearings are worn then it could have been built to tight or just show normal wear. Can you take some pictures?

[4 Jaw Chuck]

If you can't catch a fingernail on it, don't worry about it.

[gearheadslife]

Originally Posted by 4 Jaw Chuck

If you can't catch a fingernail on it, don't worry about it.

this^^^^^^^^ for most builds..