1969 350 desmo cylinder head removal and refurbishment

[neal69duc350d]

Hi all,

Valve guides are leaking oil and fouling plugs so time to have them done. Is removing the cylinder head on a '69 350 Mark3D really as easy as setting the engine to TDC and removing the 4 bolts holding it to the crankcase (per Clymer)? Can this be done without removing the engine from the frame, or will the top frame rail preclude removal?

I would like to send the head to an expert shop in the U.S. to have the work done right. Was planning on sending to Syd's Cycles but I cannot get a hold of them phone or email (still in business?). Any other shops that folks recommend in the U.S.?

Thanks,
Neal.

[themoudie]

Aye Neal,

Is removing the cylinder head on a '69 350 Mark3D really as easy as setting the engine to TDC and removing the 4 bolts holding it to the crankcase (per Clymer)?

Yes. DO NOT MOVE THE CRANKSHAFT ONCE YOU HAVE SET IT TO TDC!

Can this be done without removing the engine from the frame, or will the top frame rail preclude removal?

"Yes" to the first part and "No" to the second. However, you may need to remove the ignition coil/transducer to allow you some clearance.

With regard to contacting Syd's Cycles, maybe have a try at contacting via their Facebook page: Syd's_Cycles_facebook_link
or
via the links on their current website: Syd's_Cycles_website_link

Hope this helps, good health, Bill

[Jordan]

Bill's advice is good.
If the crankshaft is moved with the head off, you will have another job getting the crank/cam synchronization set again.
Removing the kick lever helps to ensure the crank won't move until the head is reinstalled.
Top end access on a Ducati single is delightfully simple.

[Dan C]

From bitter experience trying to sort an oil leak I can say removing the head of a 350 desmo is a "piece of piss". But after doing it four times it ought to be......
What Bill says is correct. And even if you do get the timing out of whack by inadvertently moving the kickstart while the head is off its not hard to spin the cam until the dots line up, the valves are closed and the split shaft lines up. But it saves a lot of worry if you do as Jordan suggest and remove the kickstart before removing the head.
For those that are interested the oil leak was due to the total absence of the plug at the blind end of the closing rocker pin.......A previous engine builder had omitted to put the plug in. The plug is 6mm long and to compensate a longer rocker pin had been inserted (I assume from a 450?). What a nightmare....

[Bevel bob]

My experience is that its almost impossible to ensure that something is not moved after the head is off. Far better to get the timing marks correctly aligned BEFORE taking the head off. That way you will familiarise yourself with the process and save a lot of time later. If you get the marks moved and then turn the motor a revolution to line things up you will be in a pickle with the gears in the points casing .

[blethermaskite]

Ok so I totally agree with all the above advice but can I add a couple of points......firstly I would always be most concerned about further movement of the crankshaft from TDC after the head has been removed causing the barrel to lift of the crankcase thus potentially damaging the cylinder base gasket, (I made a special short head bolt to secure the barrel when the head is off ) secondly just select first gear before removing the head that then allows you to carefully reposition the piston to TDC should it move a little.
Cheers,
George

[neal69duc350d]

Awesome, thanks for all of the pointers!

To the question about a recommended shop in the U.S. to service the head, any suggestions? Coming up empty trying to contact Syd's.

[Dan C]

Neal,

Theres a guy David Chrone in Phoenix AZ, who has had a lot of experience with singles. I don't know him but he's on Facebook in the Ducati Singles Group and the Cagiva Alazzurra group.
I think if you were able to PM him he could probably point you in the direction of a good shop in the US.

Cheers Dan

[IanHood]

"Top end access on a Ducati single is delightfully simple." - My suspicion is that Taglioni, having taken the decision to create a nightmare of bottom end shimming, took pity on us all by making top end access easy.

[Duccout]

He forgot about that when he made the vee twin!


Colin