Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > ENGINE FAILURE DISCONTINUED.....now fixed

[m1keyp]

Thanks to everyone who replied to my earlier post about my 748.

unfortunately the saga continues and the longer it takes to fix the more concerned I am about the long term.

The big end bearing failed at 5700 miles, no one at the dealers appears willing or able to tell me why, but from what I have managed to find out its possible that a grub screw worked loose and I think that you can guess the rest.

Please can someone let me know if they have had similar, should this grubscrew not be "loctited" at the factory.

Is this a design fault.

Thanks M

[Edited on 7-5-2004 by m1keyp]

[Edited on 7-5-2004 by m1keyp]

[Felix]

Is this oil galley plug on the crank that's back out, hence loosing all oil pressure on the big end, which then destroys the big end bearings? If it is, then yes, you are not the first one that's happened to. I believe this plug should be "staked".

[Shazaam!]

The crankshaft oil galley plug problem is well known by Ducati. Early-year bikes had problems with this plug backing-out. The early warning symptom is finding aluminum fingernail clipping size particles on the oil screen. If not caught in time, the plug will come all the way out and you'll get a catastrophic instantaneous loss of lubrication and big-end bearing failure.



Because it’s not staked or Locktited, when the plug backs out, it backs into the outer race of the left side crankshaft bearing. The race, being much harder than the aluminum, basically machines down the plug a little at a time until the sliver of the plug drops into the crankcase of the motor and the oil pressure light comes on. At that point, the oil pressure is used to pump the oil through the crankshaft and no oil gets to the rod bearings, crank bearings, or upper end of the motor because those places all require oil under pressure.

In a 2001 redesign, the aluminum oil galley plug was replaced with a steel plug. Ducati probably figured that the thermal expansion of the aluminum was causing it to back out.

If you've had all your oil changes done by a Ducati dealer you've probably got a good case for a warranty repair, even if you're beyond the warranty period.

It's clearly a Ducati's design defect, and in my opinion, it's fair to approach the dealer and claim that Ducati Service Bulletins and any properly (Ducati) trained service techs should have caught it.

[Edited on 5-6-2004 by Shazaam!]

[Mark853]

Sorry to say this is not the only design fault that ducati seem unable or unwilling to rectify!

I think that they call it character!

[m1keyp]

Thank you to everyone for their advice, it should be back early next week

Its "running in " will involve Monza World Superbike and WDW so please cross your fingers!