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748 Engine Refresh Thread

12314 Views 60 Replies 17 Participants Last post by  apehair
I figured I should put some of this stuff into one thread instead of posting a bunch of different ones.

Flying Bulldog helped me wrestle the bike off the engine and then lift the engine onto the jack.

No big surprises taking parts off the bike. A couple of dumb mistakes, including spilling an awful lot of coolant, but no major stumbling blocks.

Next up:

1. Remove the heads and replace the head gaskets
2. Remove the cylinders and replace the base gaskets
3. Replace the belts
4. Remove the stickers (Flying Bulldog insisted)
5. Reassemble.



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Er........That oil leak in the 4th pic. Mine had one just like it and it was coming from the vertical cylinder exhaust cam bearing cover. The screw was loose.
Serious, I've been thinking about this. My operating assumption has been:

1. 01 bike with 300 miles - gaskets have dried out from lack of use
2. Oil on crankcase - base cylinder gasket is causing it
3. Leak is big. In just a couple miles of low-rpm riding, the crankcase
is covered in oil
4. I need to pull heads and cylinders, and replace gaskets
5. It's winter, so better to fix this now than during riding season

The process of pulling the heads and cylinders is complicated and may be above my ability ... still reading the literature.

Before I proceed, do you or any of the other guys on the list think I'm making incorrect assumptions? Is this "better safe than sorry" approach misguided?


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Thanks for the link, Tricklidz. I'm currently reading the Clymer's manual for instructions on removing the heads and then the cylinders, with the ultimate goal of replacing the base cylinder head gasket. On both cylinders.

I'm worried about messing up the valve timing. And then figuring out how to adjust them again. Your blog has good notes, but do you happen to have a link to detailed procedures?


Will removing the tensioner & idler pulleys affect cam timing?

In the section that explains how to replace belts for the 748, the Haynes Manual has this caution:

Do not rotate the camshafts or crankshaft while the timing
belt is removed ... serious engine damage.

It doesn't suggest locking the cambelt pulleys with that special locking tool or anything else. So, three questions:

1. Do the cams just stay in place once I remove the tensioner pulley?
2. I'd image the same would be true once I remove the belts and idler pulley. Is that correct?
3. Once I remove the head, will the cams continue to stay aligned with the cam pulleys, or do I have to lock the cam pulleys in place?

What I've done so far (see attached images):

1. Removed the cam covers
2. Installed the crank turning tool
3. Turned the crank and discovered that there are TWO timing marks, 90 degrees apart.
4. It takes several turns of the crank to align all the timing marks
5. The vertical head timing mark says "V" on it. The horizontal says "O."

More pics in a bit ....



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Pictures of Camshaft and Driveshaft alignment marks. In the first two pics, the camshaft is aligned in the sight glass, but the belts are not. In the last three pics, everything is aligned on both sides of the bike.



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Thanks, Serious. Sounds like you had a great New Year's Eve. :)

The way Flying Bulldog explained it to me, as long as I have the crank and pulley marks in the correct location, the cams will not move when I remove the belt. But since I plan to remove the heads and cylinder, anyway, I ordered two of those pulley locking tools to keep the cam pulleys (and therefore the cams) locked.

Once they arrive, I'll remove the heads and cylinders. That should be in a week or so.

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Yess, a very pleasant new year it was.

You might find this useful if you haven't already found it:

916 Belt Change - Ducati Up North

The trick with the Tippex on the belts is a good idea.
Thanks, serious. Picked up a couple of tips from that site.

Ape, I ride my 748 ONLY when the weather is absolutely beautiful, and clean/maintain it religiously during the winter. I thought my engine was clean, until I saw yours. Am getting serious wood looking at the pics of your tear down... ;)
Prophet, I don't deserve the praise. The bike is an 01, but only had 300 miles on it when I bought it a couple of months ago. So it hasn't had much chance to get dirty, LOL.

I wouldn't mind taking the engine out of the bike and cleaning it each winter, though. Now that I've done it, it doesn't seem as daunting. We'll see if I feel the same way after I put it back together!

I've always kept my bikes pretty clean. Not quite up to the standards of Flying Bulldog, who lives nearby, but I always found the results worth the extra work.

Clarification: About those timing marks

While I wait for the pulley locking tools to arrive, I figured I'd try to post pictures in-line. Hope this works.

It turns out that there are two alignment marks on the crank. Here's the first:

And here's the second:

As you can see, they're identical. And they're 90 degrees apart on the crank. When you're on the wrong one, the pulleys on the other side of the engine are not aligned. Here's the vertical cylinder cam pulley:

Here's the crankshaft pulley:

You have to turn the crank a few times to get both sides of the engine aligned. It's not as simple as just choosing the other alignment mark on the pulley.

Just make sure you don't mistake one of these for the alignment marks:

My 748 had a bunch of them, and I have no clue what they're for. Maybe Ducati drilled holes to lighten the crank, LOL.

When everything is aligned on both sides of the engine, the pulleys look like this. Vertical cylinder cam pulley:

Crankshaft pulley:

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How do you post images in-line?

Well Hell. That didn't work.

Anybody know how to post images in-line?

Photobucket or any other image hosting service.
I used smugmug. I must have done something wrong. I'll look into it.


Removed Pulleys - Waiting for Tool to Remove Head Bolts

I'm still not certain that I needed the pulley locking tools since I had aligned the crank and pulleys according to the Haynes manual's instructions, but I decided to play it safe.

They arrived, I installed them, and then I removed the tensioner pulley, belt, idle pulley, tensioner pullley bolt, and the backing plate for each cylinder.

When I tried to remove the head bolts with the special tool I bought for that purpose, it turned out that I had the 14mm version instead of the 15mm version.
I tried using a 15mm spanner, but it didn't work too well. You can get it on there, but after you turn it, it gets stuck.

So I decided to order the CORRECT wrench this time. I'll hold on to the 14mm wrench in case I buy an 848 some day. Sheesh.

I ordered the correct wrench from: MotoReva - Ducati Tools and Supplies

I found them via this post: http://www.ducati.ms/forums/56-superbikes/64542-tools-remove-heads-749-a.html

Pics below.



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I was browsing through Sears the other day when an idea hit me. I just happen to be in the wrenches aisle and the idea popped into my head to use a 15mm boxed end wrench as my head bolt removal/installer tool. There's a twist to this though. You know what the special Ducati tool looks like right? Well how can one imitate this? Easy! Use a torch to bend the ends of the 15mm boxed end wrench 90 degrees. You could either weld a socket onto one end so you can use a 1/2" drive or simply place an allen head socket into it so you still have a 1/2" drive. Simple! Funny how things pop into your head like this :)
Not a bad idea. So you're saying you'd wind up with a 15 mm wrench that's shaped like a Z? That would address part of the problem, but you'd still have the problem of fitting the end around the bolt. There's very little room between the edge of the bolt and the head casing. :-/

Thanks, Ron, for the service manual. I also bought one to accompany my Haynes manual. It helps to have both.

So here's the latest...

1. Loosened the head bolts just fine with a 15mm spanner wrench. Just had to make sure my spanner was aligned, then hit it with a hammer a few times to work the nut loose.

2. After I removed the four nuts from the vertical head, I tried to lift the head off the cylinder, but instead the cylinder came off WITH the head. I took some pictures of the gasket and mating surfaces. The gasket had a kink in it, but it's hard to see in the pictures.

3. The correct head bolt tool finally arrived, the 15mm instead of the 14mm, so I tried it on the horizontal head, which didn't have a leak. When I removed the bolts, that head stayed in place, even though it had some force applied to it from leaning against a block of wood.

So I lubed the bolts, then torqued the nuts in a cross pattern first to 15 Nm, then to 30Nm, and finally to 48Nm. The little wrench worked great.

I have a new base gasket on order. The gasket sealant is already here. As soon as the gasket arrives, I'll begin reassembly. The Ducati service manual has a handy-dandy flowchart so I don't forget something.

I'll also pay close attention to the vertical exhaust valve cover, in case that was the problem. I suspect it was the base cylinder gasket, but I'll still check both.

Pics attached.



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Tricklidz, that's just the picture. Do you have a link to the actual blog?

I'm not planning to fool around with the valves just yet because the bike only has 300 miles. I'll probably tackle that next winter.

Thanks a bunch for the tips, by the way. I'm looking into Cometic gaskets.

And yes, LT is on deployment.

Busted a piston ring during re-assembly

Christmas and work got in the way, but I finally started re-assembly yesterday. Put on the Cometic gasket with 3-bond, and set about putting the vertical head back over the vertical cylinder. A buddy and I almost had it, but we busted the oil ring. Ping!

I ordered a new set last night, and we will try again one of these upcoming weekends. This time I think we'll pull the piston and install it into the cylinder, first, then re-attach the head, cylinder, and piston assembly to the crank shaft. What broke the ring yesterday was trying to drop the cylinder and head assembly over the piston. We *almost* had it.

Will update soon.

OK, What'd I do wrong?

I installed the new rings on the piston.

I inserted the piston and rings into the cylinder.

I added the base cylinder Cometic gasket with sealant.

I lowered the cylinder over the bolts, and made sure the piston was facing the correct way.

I inserted the pin and new clip, then dropped the cylinder all the way down and torqued the bolts.

When I tried to turn the crank, which I should have done before torquing down the bolts, it would only turn part of the way. It seemed to be hitting something.

I thought that perhaps I had installed the cylinder backwards, and the larger intake valves were hitting the top of the cylinder. But when I took it all apart again, I had installed the cylinder correctly.

After removing the vertical cylinder, the crank turned just fine again. I'm assuming that the piston is hitting the valves, somehow.

What else could it be?

Any suggestions?


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Where was I?

Near the end of last winter my progress on the engine refresh of my 01 748S stalled on account of I was seized by an episode of moto madness (see below).

Fall has arrived, I have taken the cover off the bike, and I have noticed two connectors that don't seem to connect to anything.

The first connector appears in the first three pics. The second connector is in the last two.

Can anyone offer a clue?



Moto Madness, if you must know:
- Put Harley Softail Heritage up for sale
- Bought used R1200GS
- Sold used R1200GS
- Bought 04 Honda XR650L
- Bought 10 Kawasaki 250 dual terrain (for Missus)
- Bought K1600GT
- Bought 08 Harley Softail Custom
- Sold K1600GT
- Bought R1200RT


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First one: Maybe the fuel pump connector?

Second one looks like the connector that plugs into the back of the starter solenoid.
Thanks Luke, I'll check the back of the starter solenoid tomorrow morning. And the fuel pump. I'll let you know how it turns out.

You got it in one Luke.

He sure did. That solenoid plug was a sneaky bastard. But this solution leaves me with another problem. I *thought* the 3-pronged connector coming out of the intake assembly was going to connect to the fuel pump. Since Luke disabused me of that notion, I'm now wondering what *that* 3-pronged connector connects to.

If I haven't used up Luke's good will, would he mind taking a guess? 2 pics are attached.



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