Crankshaft journal scratch

[Alexander1997]

When I was removing pistons, I believe I let one of the rods or caps come in contact with the crank journal, like a dummy. I notice a scratch now, but when I run my finger nail across it, it doesn't catch and I can't feel anything.. So I think it's very light and I will certainly be even more careful now.

My question is, with a light scratch like that, should I be thinking about getting the crank polished now? Or will it be okay for reassembly once the pistons are back from their ring job?

 

[Duner Wi]

I would make absolutely certain there is no protrusion. Is so polish witn fine emery cloth. I probably would polish even if I didn't think I could feel anything.

 

[Nordic]

When I was removing pistons, I believe I let one of the rods or caps come in contact with the crank journal, like a dummy. I notice a scratch now, but when I run my finger nail across it, it doesn't catch and I can't feel anything.. So I think it's very light and I will certainly be even more careful now.

My question is, with a light scratch like that, should I be thinking about getting the crank polished now? Or will it be okay for reassembly once the pistons are back from their ring job?

You don't have to take it in, as Duner says use a 600 grit paper over it for a bit and you'll be just fine..

 

[rustred]

When I was removing pistons, I believe I let one of the rods or caps come in contact with the crank journal, like a dummy. I notice a scratch now, but when I run my finger nail across it, it doesn't catch and I can't feel anything.. So I think it's very light and I will certainly be even more careful now.

My question is, with a light scratch like that, should I be thinking about getting the crank polished now? Or will it be okay for reassembly once the pistons are back from their ring job?

That is why it’s a good idea to slide a piece of hose over the rod studs , some use bolts. But extra care must be taken to not let anything touch the crank. Definitely needs a polish now. Probably need 1500 crocus cloth. Post a pic, what is this on? You’re not going to feel a .001 or .002 scratch. And if u can see it , the damage is there.

 

[Alexander1997]

That is why it’s a good idea to slide a piece of hose over the rod studs , some use bolts. But extra care must be taken to not let anything touch the crank. Definitely needs a polish now. Probably need 1500 crocus cloth. Post a pic, what is this on? You’re not going to feel a .001 or .002 scratch. And if u can see it , the damage is there.

Good information. Please see picture attached. Circled in red. MM ZTU

 

[560Dennis]

You’re all right with that ,that will fill with oil . remove any surface imperfections again with acceptable methods.
More importantly is the journal with in the recommendation of journal specifications using a measurements acceptable procedures.
up to you to do this with all engines wear components .

 

[rustred]

Good information. Please see picture attached. Circled in red. MM ZTU

Looking at the rest of the journal that mark dont appear all that bad. The journal should be polished anyhow even if that mark was not there. You need very fine crocus cloth. So that the final outcome looks like a mirror. These 600 grit suggestions are way too course. U need to go visit a machine shop they might give u a used belt that would fo the trick. It’s like putting polish on your truck. You’re not going to shine it with emery cloth!

 

[Mike(NEOhio)]

Real fine emery cloth or India stone. Just to make sure there is no metal raised on the edges of the scratch.

 

[Welding man]

I think I would measure the journals to know that they are in spec to start with before being concerned about the scratch. If the journal is already borderline, polishing it may put it undersize.

 

[rrlund]

I just went through that with one that was way more munged up than that one is. Use emory cloth to polish it up. What I did then was, turn the crank so that journal is down, put a new bearing in the rod and cap, put it on dry and hang it down out of the bottom of the engine, tighten it the best you can and swing it around. Take it off and see if there are any marks at all on either bearing half.

 

[JOCCO]

All the others have given you good advice and I too am with them. You can get away with a lot on these old low rpm engines.

 

[Fritz Maurer]

Just a guess, but if this is good enough to use at the drag strip, I'd say it's good enough for your tractor.

 

[Fritz Maurer]

Good information. Please see picture attached. Circled in red. MM ZTU

I think that scratch was already there. It's too far off center, and, unless you held down on the rod and pushed it sideways....

 

[rustred]

O M G. 400 sandpaper, Really.