748 Engine Refresh Thread

Serious Black said:

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.

Click to expand...

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?

Thanks,

ape

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 ....

ape

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.

ape

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:



ape

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.

ape

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.

ape

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?

Thx,

ape

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?

Thanks,

ape

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

davy.j said:

You got it in one Luke.

davy

Click to expand...

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.

ape