Hello, I was wondering if anyone knows if being off 1 or 2 teeth on your cam timing will cause the valves to hit the piston? I was changing timing belts & adjusting valves & now I have zero compression. After I put the belts & correct valve shims back I manually turned the motor 2 full cycles & didn't feel any unusual resistance & I made sure I rechecked the timing marks & double checked correct cam position with 6mm bolts thru camshaft cover, checking the second time the vertical cam didn't quite line up so I moved it 1 tooth. tried to start & it sounded like no compression, put a tester on it & sure enough, no compression, but not just 1 cylinder, I have zero on both cylinders. Is the piston to valve clearance that small that it would bend the valves being off by 1 tooth? Thank you in advance for any help given!
I don't know the answer to your main question on this engine. If you didn't use a lot of force to turn the engine manually, and you didn't hear any unusual"clatter" when you came to both churn and try and start the engine, then I doubt you've bent the valves. Is there a chance that this is to do with your shimming? If you whip the easiest rocker cover off and get the engine to TDC firing you could check for clearance on all shims and maybe determine if anything is unusual.
That's what I thought also, I rechecked them, one was a little on the tight side & I corrected it, I ended up with all valves between .05mm & .12mm. With exhaust header pipe removed on the horizontal cyl. I can see exhaust valve open & close fine from what I can tell. I think I'm going pump some air in the cyl when in TDC to see if I can hear air leaking out. It's weird, I didn't think that I bent any valves but I don't know now, & I've done this service about 6 times on 2 different Ducatis with no problems. But I guess the leak down test will tell me if I have to pull heads or not. Thanks for you're quick response to my question & I'll post what I found as soon as I have some info.
I guess you tried bumping up the compression figure by adding oil in the bores? I’m sure you already know that you can go to test an engine that’s been standing and “dry” and it will give really low figures.
Yes I squirted a little bit of oil, I guess it won't hurt anything if I put a little more in there. Even though it's only been sitting for a month, but who knows it's worth a try. I'll try this in a couple of days once it stops raining here. I'll keep you posted, & thanks again for your help
Welcome to the Forum Mario and well done @Chris for replying so promptly. I await the outcome as Ive to do my belts and Desmo service on my 2009 1100S sometime this winter
Thank you/Gracias everyone for welcoming me to the forum! Sorry I took so long to post an update on my no compression problem, I was waiting for some shims I had to order. I don't have it running yet, but I'm pretty sure I figured out what's causing the compression loss, Chris. had it right when you said maybe the valves were too tight. Oviously I screwed up, but what I can't figure out is how was I able to get a 0.07mm feeler gauge between the rocker & shim!. Even if I had checked the clearance when not at TDC, the valves would be even tighter. I don't understand, I triple checked. the tightest valves were 0.05mm. I don't know what I smoked that day but it must have been some wicked stuff!! One thing I learned, & I didn't see it mentioned in the service manual is that you should check & adjust the closing valve rocker first before measuring clearance of opening valve rocker..because if you don't adust closing clearance first the opening clearance measurement you took will be off. Well I should have it back together in a couple of days (hopefully running), I'll let you know how it everything after it's running. Thanks again everybody!
