Ducati Monster Forum

Moto Board => Tech => Topic started by: LowercaseJake on March 04, 2018, 07:32:18 AM

Title: Timing gear misalignment
Post by: LowercaseJake on March 04, 2018, 07:32:18 AM
During the course of double checking my FW, I allowed the smaller of the 2 timing pulleys, the one that turns the larger, to walk off the crank, unfortunately I turned it several degrees before realizing my mistake.

Here is a photo of the gears in question, see #12:

https://photos.app.goo.gl/aKCNQxjRpNWBwwlE2

And I found a thread that describes my event to a T;

http://www.ducati.org/forums/1098-1198/64043-timing-gears-misaligned.html#/topics/64043?page=1

I hastily removed the timing belts (plan on putting new ones on anyway) so I could easier turn the cylinders and the valve train to confirm no damage. No damage has been done but obviously my engine timing is now way off.

I'm wondering which sequence to follow in which order: replace the timing belts per the multitude of available instructions (align the dots) to confirm horizontal TDC and correct timing. Then proceed to line up the timing gears, reinstall the sprag/starter clutch/FW etc. Of course turn the motor several times by hand before start up.

Many thanks..

Title: Re: Timing gear misalignment
Post by: Speeddog on March 04, 2018, 07:45:48 AM
Confirm that all valves are seated, both heads.

Get the timing gears/flywheel/pickup triggers sorted out.

Put the belts on.
Title: Re: Timing gear misalignment
Post by: ducpainter on March 04, 2018, 09:35:08 AM
...and buy a service manual, whether it's a Haynes, or a .pdf version from duc.nu .

That will give you the procedure for installing all the left side pieces.
Title: Re: Timing gear misalignment
Post by: LowercaseJake on March 05, 2018, 04:18:39 AM
Ok dudes this is where I'm at;

The final cog, all the way towards the back of the crank which oddly won't just slip right in anymore. Note how I've circled the dots as well is the keyway;
https://photos.app.goo.gl/V3qJd7f0Suz2BSr22

Belts are removed and using Chris K's video I was able to check the valves. According to his instructions they check out fine. They operate and close just fine.

Unfortunately I can't find any marks in the drive pulley, neither on the cog or engine case. We'll get back to that.

Obviously I can spin the bigger valve train cog by hand.

VERY unfortunate that I stripped the Allen bolt on the horizontal tensioner (I wound up cutting off the old nasty belts).

Obviously this job is on hold until my talented friend with a huge collection of tools can help me extract that bolt. Good lawd they are on there TIGHT, I used my impact gun on the other tensioner.

I feel perfectly capable of checking the valves as well as reinstalling fresh belts (once again thx Chris Kelly)

The small cog that drives the larger half time cog won't slide in easily as before, this has me concerned.  Here's a pic. The woodruff key IS intact.


https://photos.app.goo.gl/pM4kgjDgiJHcFKew1

If y'all need more photos lemme know. From what I've gleaned:


Title: Re: Timing gear misalignment
Post by: booger on March 05, 2018, 10:02:10 AM
Speeddog, to confirm all valves are sealing against the seats a compression test should be performed, correct? Or is there another easier way?
Title: Re: Timing gear misalignment
Post by: ducpainter on March 05, 2018, 12:15:31 PM
Quote from: booger on March 05, 2018, 10:02:10 AM
Speeddog, to confirm all valves are sealing against the seats a compression test should be performed, correct? Or is there another easier way?
Difficult to do a compression test on a motor that won't spin.

Leakdown would be easier on that motor.
Title: Re: Timing gear misalignment
Post by: Speeddog on March 05, 2018, 12:38:03 PM
Leakdown gives a *lot* more definitive data than a compression test, as you can find where the leak, if any, is occurring.
Title: Re: Timing gear misalignment
Post by: koko64 on March 09, 2018, 02:42:35 AM
Any luck?
Title: Re: Timing gear misalignment
Post by: LowercaseJake on March 15, 2018, 04:51:32 AM
Quote from: koko64 on March 09, 2018, 02:42:35 AM
Any luck?

Jury is still out. I dropped her off at the dealer and fell in love with the idea of a 2018 Scrambler 1100 in my garage... So I might be parting out some tasty bits including a bunch of unobtanium Roadracing goodies in the near future... I did put a refundable down payment on the Scrambler but wowz that's an impressive looking bike... First Duc to come down the pipe that offers a serious challenge to my R9T "must have at some point" itch.

Thank you for asking.