Crank and big end shell help!?

[maggspower]

Hi there, I'm having a bit of trouble with selecting the above items for an m20 325i. First I must apologise for the quality of the images.





Both pics are of the same part of the crank at different rotations.

Each standard and oversize bearing has 3 other sizes within it, which is denoted by painted spots on the crank, for the main bearings the dots will be either white, green or yellow.

The top one shows the yellow dots for the mains, and the bottom one you can just see red dots on the curve of the crank web. All the journals are within spec and have been polished so all i need are standard size originals.

My conclusion is that I will need the standard size yellow bearings for the mains, but what size big ends? The realoem site seems to say half red and half blue. See part numbers 6+7 on the link

http://www.realoem.com/bmw/showparts.do ... g=11&fg=20

Any one shed some light on this?

Thanks Maggs

[maggspower]

I have, its all checked standard size, but for example the 60.00mm main shells have a further three sizes within it which may be 59.999, 60.000 or 60.001 for example but i cant find these sizes. But I know the mains size, 60.00mm standard yellow.

Its the big ends I'm struggling with do I need 2 standard reds or a standard red and a standard blue for each big end.

[baptie0]

on my m50 2.8 crank Red is for the con rod cap and Blue for the rod.

[Simon13]

ditto big ends aren't so strict in the size. Its a red and a blue you need in either 45mm and then its straight to plus +0.25mm and +0.50mm sizes. Theres no 3 colour scheme for each size if you get me?!

Bentley manual tells you the sizes for plastiguage or measuring the crank. mines not to hand at the moment for exact sizes on the mains. Best to check it i think.

[maggspower]

Thanks for the help fellas I have only used machine shop bearings in the past, But the OCD has kicked in for this one.

[Simon13]

well prepare to take it hard!! over £10 for the big end shells and ,mains and the thrust washers are £18 each PM sent

[maggspower]

PM back at ya

[e301988325i]

Is it just - yellow mains - red con rod cap - blue con rod ?

[maggspower]

Is it just - yellow mains - red con rod cap - blue con rod ?

Yes I think so. I still dont totaly understand the reason for the red dot on the crank, as it seems it can only be a red bearing half and a blue.

[Simon13]

red and blue for the big ends. One the mains they can be green,yellow and white in each size. Although bentley states sizes for red and blue main ends too! But etk doesn't show these and their sizes are covered by the other 2 colours.

I'll dig the bentley out and post up the sizes

[maggspower]

pm sent