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The engine on my 1967 Ducati 250 Scrambler has been sitting in a garage for about 25 years and seems to be seized. I cannot move the kicker to turn over the engine even with the spark plug removed.
I live in the suburbs of Philadelphia, Pennsylvania. I am wondering if I should attempt to dismantle the engine myself. It appears that I need some specialty tools to pull certain items from the case. It is a wide case motor. I do not have the required tools. Are there tools available at local stores, such as Harbor Freight that would suffice for this project.
If anyone knows of any Ducati specialists in my area, please let me know, although I don't have thousands of dollars to spend.

Any help is appreciated!

Art

Art,
Chances are the cylinder liner is rusted and has frozen the piston in the cylinder, preventing the engine from turning over. The cylinder head is pretty simple to remove from the engine. If the engine is still installed in the frame, remove the carburetor, exhaust pipe and the four head bolts. There is a special tool required to loosen the exhaust nut that secures the exhaust pipe into the head. This tool is worth owning because you’ll need it to reinstall the exhaust pipe as well as to periodically tighten the exhaust nut, which tends to work loose over time. Other than this tool, you’ll need a socket to remove the head bolts and a 5mm allen key to remove the various covers all of which are retained by allen screws. The head should then lift off the cylinder. There are two situations that could prevent this: there is a dowel pin between the head and cylinder adjacent to the left rear cylinder bolt that can be a tight fit and there is a rubber o-ring in the flange at the base of the bevel tube that can stick to the bevel tube making it difficult to separate. Don’t pry on the head or cylinder with any levers as this will bend or break the cooling fins. Squirt WD40 around the base of the bevel tube to help free the o-ring. You should be able to free the head by alternately pulling up on the front and then the rear of the head. Once you get the head off you can assess the condition of the cylinder/piston. One other suggestion is that if you intend to remove the camshaft from the head, loosen the cam gear nut before you remove the head. This is a left hand (reverse) thread and is difficult to remove once the head is off the engine. It’s also easier to remove other components from the head while it’s still attached to the engine. If the bike has been exposed to the elements, you may have water inside the engine, so you should drain the oil and determine if any water is present. This will give you an indication of what will be required to get your engine back in running condition. Condensation alone after many years in a humid environment can accumulate water inside your engine (which is why your piston is rusted to the cylinder). If disassembly procedure isn't obvious to you, ask on this site bofore proceeding as you don't want to ruin any parts! Happy wrenching! Matt

[quote= asmith411 ...
" The engine
seems to be seized. I cannot move the kicker to turn over the engine even with the spark plug removed. "

____ Have you ever yet tried turning-over the engine rather by pushing the bike while in-gear ?



" I am wondering if I should attempt to dismantle the engine myself. "

____ Before attempting to remove the cyl.head,, it possibly could be that the cyl.liner is only very-slightly rusted, in which case you may be able to SHOCK the piston loose from being stuck to the liner. ...
This can possibly be done by quickly filling the cold cylinder with boiling mineral-spirits (or penetrating-oil),
(by pouring the HOT-oil inside with funnel through spark-plug hole),
and-then next push the bike and drop into 2nd.gear ASAP.
__ This method may-not work (when the cyl.liner is too badly rusted), but may possibly save you from the more extensive work of removing the cyl.head, etc.


Hopeful-Cheers,
-Bob

OK, thanks for all the recommendations. We did not try pushing the bike in gear. Actually I don't have much space in my basement. Anyway, my son and I went ahead and removed the cylinder head and cylinder. There was minimal rust on one side of the piston and cylinder. A little twist of the cylinder freed it. I'm thinking of using fine steel wool and wd-40 to remove the rust from both. Do you suggest removing the piston from the rod? Don't want steel wool fibers to get into the crankcase.
Any suggestions on removing the carbon from the piston and valves?
I have a new problem. I removed the case cover on the gear shift side of the engine. I opened up the gear shift lever box attached with 3 screws. It's pretty gunky in there. I want to clean the parts and reassemble. I'm assuming I can grease up the cleaned parts with fresh grease for reassembly. My problem now is I'm not sure how to position the plate that rotates on the ball bearing and upper pin alignment (if you follow what I'm saying). I tried to put the box back together temporarily and it would not seat. I'm thinking that the pin alignment has something to do with that. I have a blow-up diagram but it doesn't show the alignment.
Lastly, I'm thinking of using "Simple Green" as a parts cleaner, maybe mineral spirits. I don't want a smelly solvent in my basement. Could result in divorce court.

[quote= asmith411 ...
" There was minimal rust on one side of the piston and cylinder. A little twist of the cylinder freed it. "

____ That's just the kind of minimal cyl.liner rusting that the hot-oil shock-method/trick easily deals with ! _ (So it's sort-of too-bad that you rather hastily jumped into action and didn't patiently wait a couple days for responses to your posting.)



" I'm thinking of using fine steel wool and wd-40 to remove the rust from both. Do you suggest removing the piston from the rod? Don't want steel wool fibers to get into the crankcase. "

____ I doubt it's worth the bother of removing the piston, instead just stuff some rags into the motor-case cyl.hole to catch any debris (and-also hold the piston & rod from banging into the casing).



" Any suggestions on removing the carbon from the piston and valves? "

____ I've heard-tale that there's some kind of gel that loosens it,, but I-myself have always rather used a copper/brass wire-wheel brush (installed in a hand-held power-drill), to scour-off the built-up carbon-deposit (and inevitably also polish the combustion-chamber surfaces).



" I opened up the gear shift lever box "

____ Did you also have the foot-lever removed (thusly allowing the spring-return mechanism to come-apart) ?



" My problem now is I'm not sure how to position the plate that rotates on the ball bearing and upper pin alignment "

____ Perhaps you may find something pertinent which addresses your issue, within the related thread at this link... viewtopic.php?f=3&t=979



" I tried to put the box back together temporarily and it would not seat. "

____ Do you mean that the shifter-box/eng.cover would-not fit back into place all the way onto the motor-case, or, do you mean that the gear-selector box-cover won't close-up & seal ?



" I'm thinking of using
mineral spirits. I don't want a smelly solvent in my basement. "

____ Then how-about the garage instead ?


Hopeful-Cheers,
-Bob

[quote= asmith411 ...
"That's just the kind of minimal cyl.liner rusting that the hot-oil shock-method/trick easily deals with ! _ (So it's sort-of too-bad that you rather hastily jumped into action and didn't patiently wait a couple days for responses to your posting.) "

......Sorry, Bob, my son and I are working on this. He was a little anxious to open up the engine casing. We only have 3 days a week to work on it together.

"I doubt it's worth the bother of removing the piston, instead just stuff some rags into the motor-case cyl.hole to catch any debris (and-also hold the piston & rod from banging into the casing). "

..........How do you suggest I clean the piston and cylinder of the rust? Except for minor rust and carbon on the piston head both look good. Do you suggest honing the cylinder bore and new piston rings?


" Did you also have the foot-lever removed (thusly allowing the spring-return mechanism to come-apart) ? "

.......Not sure what you mean here, I took the gear shift lever off, but it didn't appear to release any spring.


"Perhaps you may find something pertinent which addresses your issue, within the related thread at this link... viewtopic.php?f=3&t=979"

..........I'll have to review the thread more closely. The plate has more than 2 pins and many recesses for the ball bearing to rest. Hopefully I can figure it out.



"Do you mean that the shifter-box/eng.cover would-not fit back into place all the way onto the motor-case, or, do you mean that the gear-selector box-cover won't close-up & seal ? "

.........The gear selector box won't close properly. I'm not aligning the pins right, I'm thinking. The spring presses against the cover. When I try to tighten the screws they become very tight and the cover won''t close. I haven't figured it out yet. Hopefully your post you sent will help me solve it.



"Then how-about the garage instead ? "

.......Don't have a garage. I'm in a walkout basement.


Thanks for your comments,
Art

[quote= asmith411 ...
" ......Sorry, Bob, my son and I are working on this. "

____ No need to be "Sorry", as of-course it doesn't really matter to me how much work you spend on your project.



" ..........How do you suggest I clean the piston and cylinder of the rust? "

____ Just rub it away & off from the piston with whatever means works well enough for you.
__ A wire-wheel brush should remove the protruding rust from the cyl.bore, well enough. _ Some rust-spotting may still appear to be left present afterwards, but so long as the bore-surface has become rather smooth to the touch, it's then good enough to go-with.
__ The following link is to a place which has any tool-piece which you possibly ought need to address your cyl.bore-wall corrosion issues (as well as your carbon-deposit issues on piston-crown & combustion-chamber) ... http://www.brushresearch.com/flex-hone. ... aQodJooAiA



" Do you suggest honing the cylinder bore and new piston rings? "

____ If I were a mechanic at a shop (with a need to make money), then of-course such unnecessary work & parts would be recommended. _ However I know your engine will still run just as well without such extra work.
If the ring-gap for the compression-rings is not outside of the recommended tolerance-range, then your rings should still have worthy operating-life left.
And as for 'honing' the cyl.bore, there's three main-levels* for honing-operations, of-which you may possibly consider only the lightest operation (depending on cyl.bore condition). _ If your cyl.bore is near mirror-shiny, then it may ought be 'deglazed', (so that the bore-wall will then retain motor-oil a bit better),, but that really need-not be done, if the fitted piston-rings are already used & 'broken-in'.
(* Light-duty level - is done with a fine-grit multi.ball deglazer-brush [held within a hand-drill]. - http://www.amazon.com/Research-FLEX-HON ... inder+hone
Medium-duty level - is done with a fine to medium grit tri.stone honing-device [held within a hand-drill]. - http://www.harborfreight.com/4-inch-eng ... 97164.html
Heavy-duty level - is done with a med.grit multi.stone machine-honer [self-powered in machine-shops], and capable of small cyl.boring steps. - Following link is to a non-flex type of stone-head for 'machine-honing'. - http://www.amazon.com/Lisle-LI15000-Eng ... inder+hone )

Did you also have the foot-lever removed (thusly allowing the spring-return mechanism to come-apart) ?

".......Not sure what you mean here, I took the gear shift lever off, but it didn't appear to release any spring. "

____ I did-not mea-n to indicate that removal of the foot-lever would cause the return-spring to become relaxed, but-rather that it could allow the spring to spring-apart it's assembled mechanism.



" The plate has more than 2 pins and many recesses for the ball bearing to rest. "

____ Ohh,, then by: "plate", you must be actually referring-to the 'selector-wheel'. _ (As there's also a 'rocker-plate' [with it's pair of 'push-tabs'], which I had thought you might've been referring-to.)
__ When the return-spring is properly 'set', (as it was when you took the box-cover off), then everything inside will naturally be able to fit back-together as expected.
The mechanism is usually reassembled with the selector-wheel & ball set in the obvious* neutral-position -(* the only detent with close-neighboring detents), but that particular setting isn't really required to get everything back-together.

do you mean that the gear-selector box-cover won't close-up & seal ?

".........The gear selector box won't close properly. I'm not aligning the pins right, I'm thinking. "

____ How the selector-pins of the selector-wheel happen to be positioned, should-not make any difference (for getting the box-cover back-together all the way in place).



" The spring presses against the cover. "

____ I assume you must mean the coil-spring for holding-down the rocker-plate,, in which case, that's as expected to be.



" When I try to tighten the screws they become very tight and the cover won''t close. "

____ That's what often happens when a newbie 'allows' the 'return-spring' to come-undone from it's normal set location within it's mechanism-parts !
So chances-are, it came-undone sometime after you took-off the foot-lever, (in which case you thus-then should find that the foot-lever no-longer returns as it normally should).
__ Does this possible circumstance now seem to be the case ?


Hopeful-Cheers,
-Bob

OK, the gear selector box really has me baffled. I'm assuming you're talking about the horizontal spring at one end of the box. I'm not sure of its position because I didn't see its true position when I opened the box. The parts blowout doesn't show how it is positioned. I need to study it more.
Is there a diagram or picture of how the box is set somewhere?

Thanks,
Art

[quote= asmith411 ...
" I'm assuming you're talking about the horizontal spring at one end of the box. I'm not sure of its position because I didn't see its true position when I opened the box.
Is there a diagram or picture of how the box is set somewhere? "

____ You might possibly get some related insight from a couple of consecutive posts submitted by fellow-member 'Chuck', who mentions of his-own difficulty concerning his installation-positioning of a newly installed replacement return-spring. ...
As he first tried installing the return-spring in it's un-sprung/normal-state, before later finally realizing that the spring needs to be rather highly TENSIONED with it's 'tails' -("ears", as Chuck-himself refers to them) over-crossed around the two pegs which the r.spring is supposed to keep centered together.
__ So see if HIS post-wording makes any realization-sense to you, at this link... viewtopic.php?f=3&t=1125&p=7607&hilit=return%3Dspring#p7612



____ You failed to answer whether or not the foot-lever still properly returns to it's regular centered-position as it normally should. _ So I'm still left to assume that it no-longer does.
And providing that the return-spring has actually come-undone from it's functional working-position, then that could possibly explain why you're unable to get the box-cover installed all the way back into it's normal fully-seated position.
__ The 'return-spring' is shaped very-much like the CAP.letter Q , except rather with a pair of (mirror-imaged) 'tails' ! - (The "tail" of a 'Q' is the extra little-bit that distinguishes the capital-letter Q from the letter O.)
So if you imagine a Q-shaped spring with an extra tail facing oppositely of it's regular single tail, (as-if another mirror-imaged Q were laying-over/atop a normal Q),, then you should easily recognize the type of torsion-spring which you should be looking-for, to make-sure that it's still properly loaded into it's working-mechanism.
The 'return-spring' is-not as out in the open as the selector-plate's std.coil-spring obviously is, and is rather somewhat hidden by it's working-mechanism parts. _ But when you see that Q-type spring, you then ought-to realize whether or not it's pair of "tails" are properly centered against (& 'loaded') either-side of the two separate 'pegs' of the two working-parts of the return-spring's working-mechanism.
If the return-spring's Q-tails have become un-sprung out of their intended 'loaded' working-position, (as I'm suspecting),, then the return-spring could possibly be partially caught between the two pegs (which the Q-tails are supposed to be strongly pressing against). _ And when that somewhat likely unloaded situation occurs, then the return-spring mechanism has "come-undone" and no-longer properly works to return the foot-lever back to it's normally centered-position.
__ Can you now confirm anything of this, NOW ?



" The parts blowout doesn't show how it is positioned. "

____ When the return-spring is properly set between/within the other two pieces of it's return-mechanism parts, then the r.spring's pair of "Q-tails" are 'CROSSED', and-thus are then forced to be somewhat highly-tensioned with each of the Q-tails pressing-against a peg* of the two neighboring mechanism parts.
(* The 'peg' of the foot-lever's spindle is 'round', while the peg of the r.spring-holder is rather square-shaped.)
When the return-spring is properly 'loaded' into place,, there-after, appropriate care must be taken to keep the spring from launching-apart it's containing mechanism parts, or-else you'll have happen that which seems to have occurred in your presented case, (whenever the foot-lever has been removed from place on it's spindle-shaft).
__ I've come-across quite a number of shifter-boxes where-in the return-spring had been allowed to spring-apart, thus-then leaving it's mechanism 'undone',, and-then often leaving one of the Q-tails laying against the tip-end of a peg (instead of along-side it), which thusly keeps the box-cover from fully-closing (by the same gap-space as the thickness of the r.spring's Q-tail).
So I'm assuming that this same common happenstance is what has occurred in your case as well !?


____ Next question ?


Hopeful-Cheers,
-Bob

DewCatTea-Bob wrote:[quote= asmith411 ...
" I'm assuming you're talking about the horizontal spring at one end of the box. I'm not sure of its position because I didn't see its true position when I opened the box.
Is there a diagram or picture of how the box is set somewhere? "

I've photographed mine so hopefully it will help what goes where.. The arrows point to the end of the return spring and are in effect crossed over. I fiited mine by locating one end of the spring and partially fitting the gear lever and using this to turn the other end of the spring into position.. not easy to do but probably easier than trying to describe it!


Hope this helps

Ian