Ok time for an update... I managed to get the engine turning over using the flywheel bolt and a big bar. I hit the starter, it turned over. No horrible noises but it would grab and lock again occasionally, but this time requiring less force now to move it at the crank nut. on rotating the crank back and forth where it was binding on something the friction disappears? I resolved the slow straining on starting, which actually has all ways been a problem with cables etc. getting red hot. By making myself a new heavy duty cable kit and it and now spins up no problem now like a new bike.. ok. no plugs in. alternator cover back on. water, oil etc. start button.. wizzes around no problem. Now for the Biggy, plugs in. Hold my breath.. Press start.. Bike fires up..... uffff. a tapping noise. tack tack tack, not bang bang bang. from an area around the clutch basket. Could it have been the clutch basket binding all along? It has no clutch plates installed yet the basket has a little movement but I think its not that, as it seems to be firing but losing compression on the vertical cylinder. Apart from the intermittent clacking the engine at idle sounds smooth at the exhausts. on reving a little it feels like its not firing properly on the vertical head. VIDEO HERE Nick Little | Facebook Ok belt covers off.. nothing looking wrong there. no appearance of a tooth slipping and the belts are tight, I can twist them no more than 45 degrees, no sign of damage or wear on them. I'm hoping its just a valve issue and not a big end. as the sound is a clack not a Knock. before I remove the head does anyone have any opinions. I don't really want to remove the whole engine just yet. Nick
I'd be doing a compression test on the cylinders. I recently had an incident with my Lemans, where suddenly it seemed a little down on power and wouldn't run at idle but otherwise OK. Checked the compression to find one cylinder was less than half what it should be, the other seemed OK. When I looked at the valves the clearances had grown on the exhausts, turns out the pistons hit the exhaust valves but only 'gently' so no major smash-up. Now I realise that shouldn't happen on a desmo engine but I'd like to know the compression was good before running it again...
when you pulled the flywheel, did the gear come off the end of the crank with it?? The gear is key'd to the crank as well as splined, but there's also alignment marks on it and the layshaft gear to the cam belt pulleys. If these aren't aligned properly, then all will look well belt side, but the timing will be out.
thanks for the reply. as far as I'm aware the gear stayed on the crank, unless it is was stuck inside the flywheel. honeslty cant remember. But the bike ran perfectly for a number of days on the stands. it failed/ locked up whilst test riding it. red oil light flickerd then went on full. and locked in seconds.
Ok. Oil pressure issues are usually big end related. Drop the oil and look for a gold shimmer to the oil. Pull the strainer and check for brass looking material on the filter...
Thanks. there is a pic of the strainer page one. some very tiny flakes one might expect to see through wear. as far as gold shimmer in the oil.. I didn't see anything shimmering. Is it as though the oil is mixed with a little gold paint kinda thing sort of an emulsification?. Oil light.. now ok. just occasional flicker see vid above. Not a banging sound more of a clack which is not consistent per rev. intermittent. but continuous if that makes sense. also its as though its not firing on the vertical cylinder properly. Thanks Nick
I had a major engine failure on a 2000 996, it split the housings between the two cylinders, but ran, abet a little rougher than before ... I think the small particulate in the oil ( on my bike)was shim shavings from the crank wandering
Thanks duke. Vertical horizontal Within ducati specs according to Ducati 1999 workshop book??? but I have to say I googed it and it does seem low according to a few post I saw. . Mines an sps engine. So 9 on vertical and 8 on horizontal it says in the book. within limits I guess not then?. bt nevertheless I assume from that the valves are good as u say. I'm wondering if the vertical cylinder is higher compression because the piston is compressing more due to a small flat spot on a big end bearing only for the V cylinder.? .... clean plugs, not oily. dry, no fuel on that pot for some reason.Maybe 2 problems? But it doesn't explain why it is not firing properly on that one. I really am trying to avoid a engine tear out. And at the same time learning more things. I enjoy to an extent. apart from my lack of Ducati special tools. So I have been trying to avoid the possible inevitable
Not sure if the numbers shouldn't be a bit higher? but at least you've not got a silly low reading (like my Lemans that had 70psi vs 155psi) so I would think your valves aren't bent.
yep agreed. actually the numbers are spot on for either a 996 or a 996sps. according to the book. ufff 70/155. wow. I guess the left failed.
not sure which book that is Nick but I wouldn't call 110 psi 'spot on'. Did you have the throttle cranked fully open during test? If not then do it again as bound to be an improvement. Also worth repeating again with a wet test to see how much cylinders (particularly low one) bump up. You probably already know a comp test is better than nothing but results have to be interpreted - a leakage test would be better but appreciate that this is a greater outlay.
ah ok. thanks. it was a dry test. with plugs not firing just to test for leaks. so pressure from starter only. From Ducati 996 workshop manual
I'm amazed that the procedure doesn't mention opening the throttle but maybe those figures are dependent on closed throttle. Even removing other plug and Using a fully charged battery with good cranking speed will make a slight difference to the figures.
This reminded me of something I see on cars when they have run dry of oil or had oil pressure problems of some kind ........ If you get a damaged or flatted big end shell it's normally the upper shell because its the upper shell that takes the firing pounding so at Bottom dead the rod and piston can travel further downwards and in some cases the piston skirt will clip the crank webs and cause the clacking sound or .......... If the lower shell has damage or flatted or worn in some way when the piston comes to the top it has more travel so it can clip valves or clip the squish area of the head ,but .......it only clips the valves or head when the valves are open ( on the rock ) because there is no pressure in the cylinder ,on the compression stroke the compression resists the piston and it doesn't clip . This is where you get the clack but it's not every revolution , it's every other revolution .... clack gap clack gap clack gap if you see where I'm coming from Lee
Just another thought , how does the oil get to the mains and big end , does it get fed down the end of the crank where the generator is like a Aprilia Sxv 550
