CSL crankshaft bearing shell

[Chad]

Hi Chad,

Can you feel that pick up with a sharp pick? or your finger nail? If so it would need some attention. You'd also have to measure it with the plastiguage to see if its excessively worn, and to determine which shells you put in when you put it back together.

Hi Out of interest, on the 59.75 or 60.00 main shells. what is the difference in size? between yellow , green ,white shells, I take it the white shell has more meat, green in the middle, yellow the least meat..main shell,in .00mm ...... Bmw don’t give this colour option on rod shells just the two sizes 49.00 48.75. ... are the 48.75 shells for reground cranks? Or did bmw do two crank sizes, surely they never wear that much ,,, if the 48.75 are for reground cranks then bmw only do one size for rod shells , unlike mains , ..Tech minded only need reply. Unless you really want to,,, :whistle:

[Chad]

Hi Out of interest, on the 59.75 or 60.00 main shells. what is the difference in size? between yellow , green ,white shells, I take it the white shell has more meat, green in the middle, yellow the least meat..main shell,in .00mm ...... Bmw don’t give this colour option on rod shells just the two sizes 49.00 48.75. ... are the 48.75 shells for reground cranks? Or did bmw do two crank sizes, surely they never wear that much ,,, if the 48.75 are for reground cranks then bmw only do one size for rod shells , unlike mains , ..Tech minded only need reply. Unless you really want to,,, :whistle:

Anybody or I’m I missing something

[Monkey]

Anybody or I’m I missing something

Hi Chad,

You are correct there are only 2 sizes of bearing available for the big ends, and yes there is a standard size and an option for ground cranks.

As for the mains there is a wider selection of bearing sizes avaiable.

As I mentioned previously, I would only recommend using plastiguage to see which bearing shells you need.

[Chad]

Hi Chad,

You are correct there are only 2 sizes of bearing available for the big ends, and yes there is a standard size and an option for ground cranks.

As for the mains there is a wider selection of bearing sizes avaiable.

As I mentioned previously, I would only recommend using plastiguage to see which bearing shells you need.

Thanks James for confirming that regarding rod shells, as for main shells, is there any technical information as regards thickness difference of the yellow, green,and white shells on std shells, I’m assuming they are only different in 0.01. Or 0.03 difference so to speak just to take up a bit of wear on crank bearing faces. ........ Sorry to blast you with this. Also regarding ring sizes shows two different ring options for std rings, 0 and 00. I’m presuming 00 are to be used on a higher mile engine , any tech info on this appreciated ? £40 price difference also between the two different part numbers I understand measuring end gap etc. ..... Any specific end gap for csl.. thanks for your input James. ,,, speaking to my local engineer suppliers today, they say they would use the 00 term / measurements, to indicate a higher degree of machined /measured accuracy. Phil

[Chad]

Hi Chad,

You are correct there are only 2 sizes of bearing available for the big ends, and yes there is a standard size and an option for ground cranks.

As for the mains there is a wider selection of bearing sizes avaiable.

As I mentioned previously, I would only recommend using plastiguage to see which bearing shells you need.

When I’ve measured crank bearing face they come out as in photo, so std crank. Very minimal wear on this 100k crank , would have been ideal if bmw give you the option of shells as they do on main shells, especially for no 3 . :thumbs:

[Chad]

When I’ve measured crank bearing face they come out as in photo, so std crank. Very minimal wear on this 100k crank , would have been ideal if bmw give you the option of shells as they do on main shells, especially for no 3 . :thumbs:

I’ve taken picture from internet,,, What’s the recommend ideal measurement outcome for csl shells ??? I’ estimate I will see .05 plastagauge on rod no 3 shell from what I’ve measured with micrometer, tighter on others. Possibly down to .02 mm

[Chad]

Hi Chad,

You are correct there are only 2 sizes of bearing available for the big ends, and yes there is a standard size and an option for ground cranks.

As for the mains there is a wider selection of bearing sizes avaiable.

As I mentioned previously, I would only recommend using plastiguage to see which bearing shells you need.

Hi James , top marks to you mate going to the trouble of checking with plastiguage, I’m sure 99percent wouldn’t.. I’ve today been round all local autos spares, not one of them even heard of it , never mind what it’s used for.... Having established I’ve got stock crank and only the one shell available, still what is the ideal measurements outcome we are looking for , regarding plastiguage on these bmw crank to bearing face measurements, Eg 0.03 0.02 mm, Do bmw have a recommendation. ???.... sort of irrelevant I know as only one shell available , Any input also welcomed anybody :thumbs:

[Chad]

Found this on internet, bit more information , but no dimensions. Definitely plastiguage will be used to work out best one to use on mains , but could do with actual tolerance required.? Eg if the white shell has more meat on its bones,(so to speak) I’d possibly use this on Number 1 main. As this has the most wear, as this crank used green shells from new . All depending on what bmw recommed shell to crank tolerance....If anybody knows ?

[Chad]

Think this is what I need.

[Chad]

Plastiguage

Eventually got some plastiguage from manufacturers, pictures couple of main crank journals , and the two most abused rod journals, shows a basic ball park measurements of bearings wear /conditions .. to compare against bmw bearings chart in previous post. . My measurements with basic micrometer shows a slight difference to bmw spec , Will recheck with a better mic Just to check crank spec again. These are the worn bearings. So new should but them back to spec. :thumbs: Number one main crank shell seems to pull the most wear , about 0.055 mm possibly as it pulls timingchain / oil pump, .... Conrod bearing clearance. Should be between 0.030. And 0.070 mm on spec sheet,Below 0.030 is to tight bmw recommendation would be to fit another set of new shells .(... Update... ) bmw now, say min 0.040 shell bearing clearance, After that new Conrods

[Chad]

Rod bearings spec

If off interest to anybody rod Journal bearing spec and shell clearance. ........NOW from what I’ve read bmw have changed from min 0.03. To min 0.04. Retrospectively. (I’d work to 0.04 ).

[Chad]

Thanks James for confirming that regarding rod shells, as for main shells, is there any technical information as regards thickness difference of the yellow, green,and white shells on std shells, I’m assuming they are only different in 0.01. Or 0.03 difference so to speak just to take up a bit of wear on crank bearing faces. ........ Sorry to blast you with this. Also regarding ring sizes shows two different ring options for std rings, 0 and 00. I’m presuming 00 are to be used on a higher mile engine , any tech info on this appreciated ? £40 price difference also between the two different part numbers I understand measuring end gap etc. ..... Any specific end gap for csl.. thanks for your input James. ,,, speaking to my local engineer suppliers today, they say they would use the 00 term / measurements, to indicate a higher degree of machined /measured accuracy. Phil

..found ring clearance, if anybody needs to know, also main bearings shell Difference....as for ring sizes bmw shows three sizes, 0 and 00 And +0.20 From what I’ve found I think it is the bore size, as on engine block spec picture bellow, So I’m guessing not all blocks are the same, and need to be checked when ordering pistons and rings , unless anybody knows differently, ??? Possibly+0.20 is first oversized,

[Chad]

Hi Chad,

You are correct there are only 2 sizes of bearing available for the big ends, and yes there is a standard size and an option for ground cranks.

As for the mains there is a wider selection of bearing sizes avaiable.

As I mentioned previously, I would only recommend using plastiguage to see which bearing shells you need.

. Just to add to the post regarding mains shells , and colour coded shells. :banghead:

[Mike RT4]

Superb reference information :thumbs: :beer:

[Chad]

Sorry chaps but nothing better to do . So thought I’d put a comparison of new shells i have , , “”mains”” Black shell king race, silver oem yellow code shells mains inc thrust bearings, note different elongated hole in king shells. Also picture of rod shells black kings. Silver bmw, with weight of rod bearings. Will do weights of mains later. These king bearings do look to have good surface finish and look like a good quality finish.... “” Anybody have experience of the king race””.