Hi Everyone I would greatly appreciate all your experience and knowledge with the below problems. I apologise now if some of the questions seem obvious but i just want to ensure i am not making any expensive school boy errors: I have spent the majority of lock down doing some major overhauls on my Ducati 748 on a 2002 plate, its the Bisposto model. One of the jobs was having the engine covers powder coated, in order to do this i obviously had to take out all the internals including the water pump. Finally finished everything, got the bike all back together, new oil and filter (Motul 4T - 10w/40). Fired the bike up and it went first time, ticked over for a while then revved up to 6000rpm. Turned bike off and noticed both the engine oil level and the crankcase site glass had strawberry milkshake in them. I know loads of posts have mentioned condensation but this was far more. I drained the oil and you can see the state of the oil in the drain pan shown in the image below: After a lot if head scratching and contemplating what i had done, i am guessing one of the causes will be the mechanical seal. Can you please confirm that the spring faces toward the impellor? I think another step i went wrong was installing the bearings, i inserted as per the drawing below only to now realise this is for a Diavel. In the housing i inserted spacer, inner seal, outer seal with faced side pointing toward the engine. In the Haynes manual it only says bearing formation varies from model to model. I am sure when i took it apart it was inner bearing, spacer then outer faced bearing? Although its also shows the same formation as the above in the parts drawing shown below which is why i followed this. Can someone please advise what is the correct installation for the bearings, also can you please advise should the outer bearing face be showing toward the impellor or engine. The other part i changed was the crankcase bearing shown in the drawing as number 4, should the faced side be pointing outward or toward the engine. Finally looking at the state of the oil, am i on the right track thinking its the mechanical seal. Is there any where else apart from head gaskets that could cause this mush oil to get in, in such a short amount of time. In order to flush out all the water and emulsified old oil, once drain i was going to pour through pure alcohol as i understand this chemically reacts removing the water and evaporates very quickly, would this work? I would then obviously flush through with cheap oil a few times before filling with decent stuff. Any advise greatly appreciated.
Always follow the parts diagram for reassembly. Ducati Omaha have really high quality schematics you can view online or download. On that basis: - The mechanical seal spring faces towards the impeller. - The seal (reference 26) needs to cup around the other end of the mechanical seal. As regards bearing order (in the direction of impeller inwards): - Spacer, bearing, bearing, washer. Caged roller bearings generally don't have an orientation unless a circlip fits in the body or it's of a very specific design. My feeling is that you've got the seal that fits on the other end of the mechanical seal the wrong way around but that's just a hunch. You need to take the impeller out and check. As regards getting rid of any residual water/moisture I'd of thought some engine flush would work OK, then with your cheaper quality first fill oil get it really hot and drop the oil straightaway. Have a look at what's in the pan and go from there.
Many thanks for taking the time to respond, i really appreciate it. I am awaiting all new seals and bearings to be delivered so once installed i shall let you know if it resolved the problem.
I know it's a bit late now, but take pictures of everything on disassembly so you can always put it back the way it came apart, even write notes. It's easy to think you'll remember but often some time has gone by and the memory can play tricks. Putting stuff down in order can be a problem too as things often get disturbed. Good luck with your next build....
Hi Everyone Just in the process of re-building the water pump on the Ducati 748 and wanted to double check that i am inserting the mechanical seal in the correct direction before i fully push this home. Also i have read on afew other posts that you should put some sealant around the base, is this correct as it does not mention it in the manual.
