Spun #4 rod bearing. Is this a known issue?

I'm working on a 99.5 jetta, 130K miles, an Ebay purchase which was not running when I got it and previous owner had it looked at by a VW mechanic he knew who said injection pump needed work/replaced. I put a seal in the IP and did the fuel sending modification in the tank. Got it running after priming and decided to take it out for a test drive.

Got about a mile from home and the motor locked up solid. Went from a very good day to total disaster. Off came the timing belt , head, and transmission and it was still locked solid. This left me with the bearing caps and thus the #4 rod bearing.


The crank is now at a local machine shop and the machinist says it will be no problem saving the crank, he said I must have caught it pretty early on.


Now, the PO had intended to fix the car but didn't get around to it and bought another car so this engine has been sitting idle for about 5 months and a guy at the machine shop thought maybe the oil had drained out of the bearing and was dry when I started it. On a side note the#4 rod bearing cap is marked "55" (.055 mm I assume) the other three are all "65".



I noticed that World Impex sells Glyco main bearings with this description:

STANDARD- W/ A 360 DEGREE OIL CHANNEL ON #4 BEARING TO IMPROVE OIL FLOW TO THE CONNECTING ROD BEARING.

It's the part about the 360 channel to #4 bearing to imporove oil flow that has me wondering about this being a known issue. Should I install a set of these bearings while I have everything apart? What else should I think about replacing while it's all torn down.

Sorry this got sso long, thanks for reading.

I haven't heard of any known issues, though it makes sense. Just put a set of those mains into my engine recently.

You might as well do all the rods and mains, front and rear crank seals, new piston rings and hone out the cylinders. Make sure you get new bolts for the connecting rods and mains as well as new head bolts. They are TTY bolts and are one-time use only.

If you dont have a Bentley manual, get one.

Bottom-end-bearing failures on these engines are extremely rare. When it happens, a common underlying cause is that the engine was run out of oil at some point; e.g. because someone ran over an obstacle and punched a hole in their oil pan ...