Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > Only running on 1 cylinder

[Karl]

Just before you lost power did your bike make any strange noises like back-fire or anything? If you come to a dead end trying to fix it you could try Alan at AJ Racing, he`s not far from you at Charfield.

[Braai Boy]

Hi Chaps and Chapesses
Hope you don,t mind having a none Duc rider on here but I'm Kiwi Chick's other half and therefore been doing a bit of work on the bike myself. OK so the problem is the cam belt did snap but looking down the inlet port the valves are intact and seated properly the only thing is the 2 pullys are very tight compared to the rear cylinder. So I'm thinking that something in the head has seized causing the belt to snap. I have now dropped the engine out and will have a go at taking the head off over the weekend to have a look see.

[Braai Boy]

Sorry peeps where me manners? Thanks for all your help so far and to come hopefully. Now where did I put that spanner

[keefer]

Nasty business
I would be surprised if it snapped due to something seizing but either way the head will have to come off to inspect how bad the damage is. If the valves are intact they may well be bent.
Keep your eyes pealed on flea bay for some second hand heads. But as you say first step is to whip her out and have a look.
Hope it gets better from hear on in Mate
someone with moor knowledge than me will be along shortly

[TP]

Kiwichick ... braai boy ... I like bbq's myself

Good to see more antipodeans on this site.

[rockhopper]

Probably much easier to take the head off with the engine in the frame i would have thought!

[rockhopper]

My guess is that the idler pully has seized which has caused the belt to break. Becasue there are no valve springs (only a light helper spring) in theory it should be possible to turn the engine over by hand (with the plugs out). When the belt broke i think its likley therefore that it didnt stop with all four valves closed becasue there isnt much spring pressure on the cam to make to turn that little bit more. So i think that the piston has clouted the valves good style which has bent something in the head which is preventing you from turning the cams. You need to run the valves along a piece of plate glass to see if they are less than obvioulsy bent.

Has the bike been standing for a while? Has it has a recent belt change? Do the belts have white writing on them (old glass fibre reinforced ones) or red writing (newer kevlar fibres)?

Did it come from a dealer or a private seller? I'm guessing private because you are having a go at fixing it your self.

[nelly]

I'd guess you've bent a valve or two. That's why the pulleys are tight, the clearances have gone on the rockers.
When the head is off, check the valve guides as they are known for splitting.
Check also the conrod play. There will be some side to side and possibly even a little "rock" but you don't want any radial movement.

I've got a couple of 748 head s lying around if there is a lot of damage

[misterpink]

sorry that your first experience is not all good - you will find that ducati people are always keen to help out, just look at it as another way of "bonding" with your machine - mines a steinlager at the bar.

[Braai Boy]

the bike has been standing for a while 75 miles between last MOT and current. The belts have no writing on at all but I suspect they are the originals as there's no mention of them been change in the history. It was the first thing to do when I got it home just didn't quite make it that far
Nelly thanks for the offer on the heads I will let you know when I take it apart on Sunday hopefully.
I dropped the engine out cause my mate has a better workshop than me and it will also be a good oportunity for Kiwi Chick to give it agood clean.