crankshaft gear wheel shattered

Post by **wibble_puppy** » Sat May 24, 2008 7:49 pm

hi guys,

was trying to finish off fitting my duplex timing chain kit just now, and the crankshaft gear wheel didn't want to go on to its shaft once the woodruff key was in place. A piece of the gear just shattered clean away, like a chunk out of the edge.

Anyone else had this happen?

wibble

Post by **bigginger** » Sat May 24, 2008 8:03 pm

Yes. The answer is in lining it and the cam gear up absolutely precisely, then they push on with finger pressure only. Don't use a hammer (or a bigger hammer) as it always breaks them.

Post by **wibble_puppy** » Sat May 24, 2008 8:22 pm

cheers BG. This fella SOwasn't going on with finger pressure only! Must have been the woodruff key.

Well, lesson learned and all that. At least ESM have replacements in stock atm.

Post by **bigginger** » Sat May 24, 2008 8:26 pm

It will have been - it can be a hell of a fiddle, but don't force it until it's right.

PS I hate them as much as I hate split pins...

Post by **wibble_puppy** » Sat May 24, 2008 8:37 pm

bigginger wrote:PS I hate them as much as I hate split pins...

they do seem to be a major design flaw! not just in Minors but used in lots of cars.... there must be a better way

Post by **bigginger** » Sat May 24, 2008 8:43 pm

A grub screw arrangement springs to mind
a

Post by **bmcecosse** » Sat May 24, 2008 9:02 pm

It has to take the not inconsiderable driving force of turning the camshaft with 8 valve springs pressing on it, and the oil pump. A key is the only reasonable way - although of course a splined shaft would be better. A grub screw wouldn't last two minutes. the gear should be a good press fit - try it first with no key fitted to make sure no burrs etc - then install the key and it should still slide on easily.

Post by **wibble_puppy** » Sat May 24, 2008 9:06 pm

bmcecosse wrote: the gear should be a good press fit - try it first with no key fitted to make sure no burrs etc - then install the key and it should still slide on easily.

Yeah it went on absolutely beautifully without the key there - had it on and off a few times installing the shims behind it (checking there were the right number to align the gear teeth correctly). Then - woodruff key - madness!!

Post by **bmcecosse** » Sat May 24, 2008 9:11 pm

Ah well - pity you didn't stop when it became tight. The key can easily move in the slot and become wedged under the rear edge of the gear - just where you can't see it!!

Post by **wibble_puppy** » Sat May 24, 2008 9:13 pm

i think that must have been exactly what happened, judging from what I saw when I managed to lever the gear wheel off again...

Post by **bmcecosse** » Sat May 24, 2008 9:14 pm

See other post - Minsport have the key for 81p. http://www.minisport.com/acatalog/Mini_Crankshafts.html

Post by **wibble_puppy** » Sat May 24, 2008 9:45 pm

blimey! what on earth causes the vast difference in cost between suppliers? Is one made to higher spec than the other?

Post by **Packedup** » Sat May 24, 2008 9:47 pm

bigginger wrote: PS I hate them as much as I hate split pins...

I always used to hate split pins, especially ones on hydraulic master cylinders, buried behind dashboards.

Then I had to do the clutch cable on my Metro. I have a new hatred.

Post by **bigginger** » Sat May 24, 2008 10:03 pm

Lovely to put in, not so good when you're removing ones that have been in and exposed to road muck for 40 odd years

Post by **youngun** » Sat May 24, 2008 10:39 pm

bigginger wrote:A grub screw arrangement springs to mind
a

Until you want to remove one thats been on for 50 years..................Woodruff keys are much better. I have a small collection of stationary engines, many of them have their flywheels held on by a taper key and a corresponding grub screw, they are an absolute pig to remove! However, one engine (an Armstrong-Siddeley) has a woodruff and taper arrangement, all you do is screw in the correct puller to the flywheel and off it comes, the flywheel on my engine had been on there for 45 years outside in all elements and it came off no trouble.