Mk3 Excessive End float?

Previously steve_elston wrote:

Previously mike_steer wrote:

Just measured end float off of the crank on my 850 Mk3 rebuild and it came out at 80 thou. Brand new superblends in. I know I need to get it down to about 20 thou but putting 60 thou of shims in seems excessive. I don't remember seeing any shims when I pulled the engine apart. Your views

Hi Mike

I had an end float problem on my 850 mk3 being excessive

I cant remember how far out it was out of the recommended limit which should be between .005"/.015" but had to manufacture my own shims from steel/brass shim stock as the club shims are only .003"thick

good luck steve

Steve thanks. I will machine my own shims for this project this week sometime. Did you make one shim or did you divide the end float between the two bearings, in my case 30 thou each side. I know the key way has to taken into consideration.

Previously steve_elston wrote:

Previously mike_steer wrote:

Previously steve_elston wrote:

Previously mike_steer wrote:

Just measured end float off of the crank on my 850 Mk3 rebuild and it came out at 80 thou. Brand new superblends in. I know I need to get it down to about 20 thou but putting 60 thou of shims in seems excessive. I don't remember seeing any shims when I pulled the engine apart. Your views

Hi Mike

I had an end float problem on my 850 mk3 being excessive

I cant remember how far out it was out of the recommended limit which should be between .005"/.015" but had to manufacture my own shims from steel/brass shim stock as the club shims are only .003"thick

good luck steve

Steve thanks. I will machine my own shims for this project this week sometime. Did you make one shim or did you divide the end float between the two bearings, in my case 30 thou each side. I know the key way has to taken into consideration.

Hi Mike

I'm certain that I centralized the crankshaft by shimming both sides , The shims/spacers I made were just placed between the main bearing outer and crankcase inner faces like the original spec ( roughly 2.75"o/d x 2.25" i/d x whatever thickness you require)

I wouldn't put all the shim on the timing side although the timing gears are straight cut and the timing not effected, it may put stress on the cam chain by being mis-aligned

it may be worth putting a steel rule across the cogs

good luck steve

Steve again thanks. Its what I'd like to do and makes logical sense to shim each side. However from an engineering point of view that might not be the case. Ill put a general post on here and see what the replies are. Probably very contrasting, all one side or equally split, lets see.