Incomplete Oil Change

[ebmenzel]

Hi folks,
has anybody of you wondered why a dry ST 1100 (new engine) needs 4.3 litres of oil and any subsequent oil change including new oil filter is just 3.7 litres?

Here's the reason: the clutch is working in a separate oil compartment, the oil from the top of the engine flows into this compartment and part of the oil pump is acting as a scavenger pump to circulate the oil and mix it with the rest of the oil under normal operation.

This compartment holds 0.6 litres and is not drainable!

So whenever you change your oil on the ST 1100, the new oil is mixed with the old remaining 0.6 litres of old and contaminated oil. When pulling the oil pan you end up with a little mess.

In order to achieve a "complete" oil change I have come up with a solution that is described in pictures 1 thru 3: I drilled two holes into the oil pan, one from the bottom of the clutch oil compartment and one under an angle from the thread of the drain bore so that the holes meet in the oil pan wall. The drain bore hole is sealed by a silicone gasket in the drain plug. Whenever the drain plug is removed for an oil change, the clutch oil compartment is drained as well.

Works fine!

BTW, look at what I found at the oil strainer, not just on one engine, but on two different engines built in 1991 and 1998! Did not harm the engines thou, thanks to the sieve.

Best regards Eberhard

 

[Bush]

Looks like you should have been on the team at Honda in Germany when they were designing the ST1100! Good job!

 

[Jim Van]

So where the heck did those metal pieces originate ?? I may have to pull my oil pan to do your mod & see what I can find - it's an easy job.

Question - After you did the mod, how much oil did it take to refill after draining , and how many biers consumed during the oil change ??

 

[MaxPete]

Wow - that is a very interesting modification! I am startled at the debris you got out of there - NOT very nice to have that floating around in an engine (although the pieces are so large, they can't likely get into anything). The real concern would be with stuff that is much smaller than those bits - and is suspended in the "clutch oil" non-drainable region of the engine.

Good job!

Pete

 

[MaxPete]

Those pieces look like chips left behind by the many machining processes on the engine block during its manufacture waaaaay back at Uncle Soichiro's Toy Factory.

Nearly every engine ever built will have some of that sort of debris in it and engine builders go through several steps to remove that stuff after the machining operations are completed. As I said, what remains usually isn't harmful because it is normally trapped in a spot where nothing is moving. Also, the pieces are so large that they cannot move through the engine to a bad place (like a bearing journal for instance). Of greater concern to me is the percentage of the total oil volume that isn't accessible during a normal oil change - and from Eberhard's information - nearly 15% of the oil in an ST1100 remains behind after a conventional oil change. That seems high to me - but I suppose a number of engines may have similar numbers.

Pete

 

[Mellow]

Those pieces look like chips left behind by the many machining processes on the engine block during its manufacture waaaaay back at Uncle Soichiro's Toy Factory.

Nearly every engine ever built will have some of that sort of debris in it and engine builders go through several steps to remove that stuff after the machining operations are completed. As I said, what remains usually isn't harmful because it is normally trapped in a spot where nothing is moving. Also, the pieces are so large that they cannot move through the engine to a bad place (like a bearing journal for instance). Of greater concern to me is the percentage of the total oil volume that isn't accessible during a normal oil change - and from Eberhard's information - nearly 15% of the oil in an ST1100 remains behind after a conventional oil change. That seems high to me - but I suppose a number of engines may have similar numbers.

Pete

I don't see a problem, I agree w/comment about left over stuff during the machining process.

It's not important to replace 100.000000% of your oil, only to change it regularly. If 15% of the volume is left behind, it's not like it's stuck to the bottom. It will mix with the replacement oil and become diluted, there's enough flow that it shouldn't matter. If it did matter, we'd have many engine failures over time and mostly to the older ST1100s but those just don't happen often at all, they are quite rare and odds are metal fatigue within the engine will be a bigger issue. This isn't something I'd personally worry about as I would think any REAL damage would occur pretty soon as the bike was still new and under warranty.

 

[SMSW]

Regardless of what percentage of the oil is not changed because of the clutch sump, practical experience (the number of ST's out there that have worn out due to lubrication problems) shows it is not something to keep us up worrying about at night. Same with the chips. Probably be better to worry about a turbine blade breaking free from a jet, arrowing down to spear your front tire, causing you to veer into that open manhole, upending the bike, and making you spill the water in your hydration system.

 

[Mellow]

Regardless of what percentage of the oil is not changed because of the clutch sump, practical experience (the number of ST's out there that have worn out due to lubrication problems) shows it is not something to keep us up worrying about at night. Same with the chips. Probably be better to worry about a turbine blade breaking free from a jet, arrowing down to spear your front tire, causing you to veer into that open manhole, upending the bike, and making you spill the water in your hydration system.

oh great, thanks!... now I gotta look up...

 

[MaxPete]

Yeah - I never thought of that.....SCARY!!

 

[Mellow]

Apologies to the original poster.. it's cool to see someone dig that deep into the bike and it is very useful information. Please don't take the joking in the negative view... we tend to joke around here a little... but just a little.. lol

 

[Upt' North]

Yes, and what if you are riding next to water and a propellor blade snaps off and takes your helmet off, or what about sharks. OK I'll stop there.
NO ENGINE WILL DRAIN COMPLETELY ON ANY OIL CHANGE.
Can you imagine the BMW, Volvo, Ford mechanic waiting for hours for the last drop to drip into the drain tray.
A small amount of old oil won't hurt especially has it's changed so darn regularly. Or it should be.
Upt'North.

 

[Al st1100]

Regardless of what percentage of the oil is not changed because of the clutch sump, practical experience (the number of ST's out there that have worn out due to lubrication problems) shows it is not something to keep us up worrying about at night. Same with the chips. Probably be better to worry about a turbine blade breaking free from a jet, arrowing down to spear your front tire, causing you to veer into that open manhole, upending the bike, and making you spill the water in your hydration system.

agree !! Automobile engines are the same also. You cant drain all the oil from passages and the oil pump. But what worries me about the extra hole is that the clutch system is oil bathe, now if the bike sits for a few months is all the oil squeezed out of the plates and the first time you use the clutch the discs are now dry in stead of soaking. Does that also keep the oil from staying in the gear section of the transmission. I'm pretty sure there are lots of metal particles at the bottom of the in some pockets of the transmission.

 

[punder]

I would put this under the file of do if I had a good reason to remove the oil pan as a mod that is worth while doing. I wonder if you could not use a tube and a syringe to suck that area out thru the oil plug?

 

[Bush]

agree !! Automobile engines are the same also. You cant drain all the oil from passages and the oil pump. But what worries me about the extra hole is that the clutch system is oil bathe, now if the bike sits for a few months is all the oil squeezed out of the plates and the first time you use the clutch the discs are now dry in stead of soaking. Does that also keep the oil from staying in the gear section of the transmission. I'm pretty sure there are lots of metal particles at the bottom of the in some pockets of the transmission.

Al makes a good point. Even while running, that oil "reserve" in the clutch is always there and likely keeping the plates wet while rotating through the permanent bath created in that space. Having that constantly drained could starve the clutch plates for oil. Hopefully the OP will report back if he experiences clutch problems now.

 

[Bueller]

You guys should see what gets left inside the sump of a locomotive engine......pieces of previous failures, nuts and bolts, the occasional tool that gets dropped, rags, old main/rod bearings....

Frank

 

[TerryS]

Of greater concern to me is the percentage of the total oil volume that isn't accessible during a normal oil change - and from Eberhard's information - nearly 15% of the oil in an ST1100 remains behind after a conventional oil change. That seems high to me - but I suppose a number of engines may have similar numbers.

Pete

I took a look at a few of the Honda service manuals that I had to hand as they all list oil capacity at disassembly, for just the oil change, or for oil and filter change.

Worst offender in my list was the VFR800 where 18.4% remains after an oil and filter change. The ST1300 was next at 17%, then the ST1100 and GL1500 at 14%. The VTR1000 retains 13.3%, CBR600F 11% and the best of the bunch is the CBR954 which retains just 7.5%.

As an opinion/observation, the VFR800, the STs and the GL1500 would all be considered some of the better engines for long term durability, so one might conclude that the retained oil volume is of no consequence.

 

[dwalby]

one might conclude that the retained oil volume is of no consequence.

+1

Every motor vehicle in the world is designed this way, and has been for decades. If this problem needed solving, its very likely some automotive engineer would be way ahead of us.

 

[SMSW]

You guys should see what gets left inside the sump of a locomotive engine......pieces of previous failures, nuts and bolts, the occasional tool that gets dropped, rags, old main/rod bearings....Frank

Not to mention the left overs from lunch, the plastic flatware, a magazine or two, and that wrench nobody could find....

As an opinion/observation, the VFR800, the STs and the GL1500 would all be considered some of the better engines for long term durability, so one might conclude that the retained oil volume is of no consequence.

So that would make the old oil in the ST beneficial since its such a long lived engine. Hey, maybe we are looking at this backwards. The old oil teaches the young oil where to go, how to lube, what to watch out for...(that nasty filter....).

 

[Jim Van]

It's such an easy job to remove the oil pan on the ST1100. I'm going to remove mine just for S&G's and out of curiosity to see what debris I can find after 85K miles.

I'll do the mod, too. Why not ?? It can't hurt.

I want a better ST1100 !!!!

 

[ebmenzel]

agree !! Automobile engines are the same also. You cant drain all the oil from passages and the oil pump. But what worries me about the extra hole is that the clutch system is oil bathe, now if the bike sits for a few months is all the oil squeezed out of the plates and the first time you use the clutch the discs are now dry in stead of soaking. Does that also keep the oil from staying in the gear section of the transmission. I'm pretty sure there are lots of metal particles at the bottom of the in some pockets of the transmission.

Al,

the extra hole for draining the clutch is only opened when the drain plug is removed. Under normal operation the silicone gasket on the drain plug blocks the additional hole so the oil remains in the clutch compartment.

I have tested the solution successfully during the 2016 season with no adverse effects on the clutch.

Regards Eberhard