Hi all
About 6 months ago I had my crankshaft polished need due to a seized engine
I covered up the crankshaft but I’ve come to install it and found I’ve got a light spots of rust on some of the journals , I thought I’d coated them in oil
Obviously I need to remove these spots
Can I either use a fine grade wire wool or 1200 wet and dry paper without marking the journals
Or does it have to go back the the machine shop
Don't use sand paper or emery cloth. Really it should be remeasured but if with wire wool you can shift it and it looks ok you might just be lucky, I would remeasure it for if there are any defects it's better to remove them now than find a bearing has spun with the secondary consequences from that (new conrod and/or line bored block or new block if you already have O/S OD bearings).
Sandy
If you manage to remove the rust spots with wire wool give the journals a good polish afterwards, this is the method I use and get good results, it's not a quick job though! https://youtu.be/q1BsdExMbZU?si=QgCwFlnOf73MHIE8
My biggest fear is that when i die my wife will sell my tractors for what i told her they cost
The polish will alter the dimensions, measuring is crucial, any failure to specs will require a regrind. And make sure everything is clean, or the same problems will happen as if there are imperfections.
Sandy
I have polished cranks on BMWs, Ford RS200s, bikes and autograss race engines as well as countless tractor engines and never had a problem. Always use plastiguage to check tolerances, but I agree that any pitting will pick up on the shell bearings. I start with 600 wet and dry and progress to 1500 and use WD40 as a lube,, definitely not sand paper or emery cloth, if that doesn't remove any marks (light scratches) then it needs a regrind. Using a thick assembly lube between the bearing caps and shell bearings will give a false reading on the plastiguage tolerance check, although the tolerances on an older low revving diesel engines are alot more forgiving than those on a high rpm performance motor. Clean it all with brake cleaner when finished and spray it through all the oilways to ensure they are spotlessly clean
My biggest fear is that when i die my wife will sell my tractors for what i told her they cost
