Big end bearings - old part number

I've taken the pistons out of my 300tdi, the big end bearings are nicely worn, so I want to replace. They have a part number on them ERC8841 - I can't seem to find any other markings on them and web searches etc give no details of this part number. Do I assume that they are just standard size?

Hello Adrian,
Never make assumptions. They can be costly.
For what it is worth, go to the extra effort and measure the crankshaft (as best you can) and remove any doubt as to what size replacement bearings you will need. As a footnote the crank journals may be out of spec as well
Regards
John W.

ozm29c said:

Hello Adrian,
Never make assumptions. They can be costly.
For what it is worth, go to the extra effort and measure the crankshaft (as best you can) and remove any doubt as to what size replacement bearings you will need. As a footnote the crank journals may be out of spec as well
Regards
John W.

Click to expand...

that is true although usually they are clearly marked if oversized, i should imagine if you can read the part numbers clearly then they are not worn to the extent that its no longer visible.

Quick measurement shows that as far as I can tell they are standard sizes. I'm gonna replace the piston rings at the same time and I notice that the piston assembly with new rings is only a few quid more than the rings alone (on paddocks). Is it worth me spending the extra couple of quid and save me having to clean the old pistons?

if its not much more then i would go for it, seems silly to go that far and not do it if its not much more money, not really much more work either seing as your replacing the rings anyway.

Use a micrometer and measure the very edge of the bearing shell near the tang or take it to an engineering shop, that will tell youi if it is std or whatever.

regards

Dave

The seem to be standard size which is good. Interestingly one of the pistons has what appears to be a dent in from the valve... old injury or new I've no idea. I think I may just go out there and buy new pistons. Anything else I need to check or be worried about?