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Issue with setting end float on new short block (1.775mm to fill!)
bajachris88 - February 11th, 2014 at 06:42 PM

G'day!

I'm setting up end float on this new short block. Its a new CB case, new chinese cw crank, new vanadium flywheel, std oem bearings.

With no shims, i have approx 1.775mm of crank float to shim up. For 0.001 inch clearance for each shim, this equates to approximately 5 x 0.36 mm shims and 1 x 0.32 mm shim to get desired end float :crazy:!

With the end float taken up, there is no binding of crank on the case inside. I really don't want to strip down the short block again after all the effort of assembly. Crankshaft engineering already did alot of work on the crank with machining bearing clearances for big ends and mains, rods, balancing, and flywheel runout issues with main seal. (On that note, they made mention that brazilian oem std vw factory bearings showed terrible inconsistencies for tolerances between the bearings).

Can I just run the shims, given there is no binding? I'm under the assumption that the excess endfloat is the result of the addition of lots of 'error' / deviation from oem specs given every component is aftermarket (dimensions of case thrust surface machining, crank, flywheel and even the oem thrust bearing). Do i need to machine the flywheel instead perhaps?

Any help / wisdom greatly appreciated.

thanks
concerned Chris :(

psimitar - February 11th, 2014 at 07:51 PM

Easiest thing to machine would be the flywheel but crank nose would be the better one to machine.

I mean, some say that so long as you use odd number of shims then it's all good but I'd prefer to use what VW recommended :)

Oh, if you are using the metal gasket on the crank nose then discard that. Later cranks only need the f/wheel O ring. That'll take 0.25mm from things.

matberry - February 11th, 2014 at 10:12 PM

If it was me, I would do what is necessary to run the correct 3 shims. The issue is either the crank and flywheel match or they are not going all the way home when checking.

MickH - February 11th, 2014 at 11:49 PM

I'm with Mat on this one....only use 3 shims. Have you tried a different flywheel??

ragged - February 11th, 2014 at 11:56 PM

With no shims, i have approx 1.775mm of crank float to shim up. For 0.001 inch clearance for each shim, this equates to approximately 5 x 0.36 mm shims and 1 x 0.32 mm shim to get desired end float :crazy:!


Chris, My calculations for the above shims will not give you any end float. (5 x 0.36) +0.32 = 2.12mm ??? Dave

bajachris88 - February 12th, 2014 at 08:15 AM

Quote:
Originally posted by ragged
With no shims, i have approx 1.775mm of crank float to shim up. For 0.001 inch clearance for each shim, this equates to approximately 5 x 0.36 mm shims and 1 x 0.32 mm shim to get desired end float :crazy:!


Chris, My calculations for the above shims will not give you any end float. (5 x 0.36) +0.32 = 2.12mm ??? Dave


Bugger! I'll check the excel spreadsheet when i get home, i must have a typo somewhere. maybe it was 4 x 0.36 and 1 x 0.3 i typed in the spreadsheet.

I got 2 x 0.32 and 1 x 0.3 at the moment with a mile of end float left :lol:.

Thanks gents, for the tips. I haven't got a spare 8 dowelled flywheel. Its meant to be some ducks nuts chrome vanadium, with work already done in sorting some main seal runout issues. I don't want to go to the effort of shortening teh crank, i think the most inexpensive option would be to machine the flywheel. You gents agree?

thanks again,
Chris.

psimitar - February 12th, 2014 at 06:22 PM

Yup, when I said easiest I also meant cheapest :)

vwo60 - February 13th, 2014 at 10:27 AM

Simplest thing to do would be to machine the mounting face of the flywheel the amout you have calculated, not hard to do, just a bit of time setting it up.

matberry - February 13th, 2014 at 11:35 AM

Quote:
Originally posted by vwo60
Simplest thing to do would be to machine the mounting face of the flywheel the amout you have calculated, not hard to do, just a bit of time setting it up.
x2