Wisconsin VF4 rebuild questions

2. What should I look for to identify excessive wear on the pistons or crankshaft? There are a couple of small scares on the crankshaft where the piston rods go. How would I fix this or know they are ok as-is?

3. Would it be recommended to replace the crankshaft bearings while its apart? Are there other wearable surfaces/parts that should be replaced at this point? 4. Are there any things to watch out for or tips I should follow at this point in disassembly/cleaning? I am sure there are another 100 questions I can come up with but not right this minute. Any pointers to information helpful on this process would be greatly appreciated.

The crankshaft bearings seem to last forever. The tapered roller bearings should be OK unless they are damaged - look for pitting, chipping, discoloration, and rough spots.

A few small scores on the rod journals, if they can be cleaned up with fine emery cloth, are probably not a problem. Check the roundness, and check the clearance. You need a 1" - 2" micrometer and plastigage to do this. Does your engine have insert-type or the babbit-type bearings? You will need to keep track of the shims for the babbit-type rod caps.

The VF series is a real straightforward engine. It has fewer pieces than any engine I have seen. Why are you tearing down your engine? Any problems / symptoms that you can advise of?

Thanks for the tips. I will check the crankshaft later this week and may take it to a machine shop to be checked in depth just to make sure.

This engine has been sitting for about 20 years and we did not know the previous condition or when it was last serviced so we wanted to completely tear it, inpect everything and confirm that it will serve us for years to come. No other known issues at this point. Now if I could only locate a replacement manifold (alternate, low-profile style)...

The engine is part of a park train locomotive from the Birmingham Zoo. Hopefully the train will be put back in operation in the next year or so. We have another locomotive with identical engine but it is currently locked up and we don't know the cause. It will take a lot of work to pull it without being able to turn it. That will be a project for another year.