Motor Sailing

[Sea Slug]

I have a Yanmar 3YM20 with which I do alot of motor sailing, I understand that there is a possibility that extended piriods of healing is not good because the oil does not get spread throughout the engine, I have scanned through the manual, but cannot find any referance, can anyone help?

[mrohr]

I dunno, but find motor sailing is a neat solution to getting upwind when pressed for time ,esp. against steep chop in a seaway.I keep heel to minimum by use of the traveler while keeping the main full and pulling.I keep oil topped up and will tack up wind as necessary.
My contessa is quite weatherly so if conditions and /or course are such that any heeling is generated beyond, say 10 degrees,I then have the circumstances that do not require the assistance of the iron beast below.
Have used this technique for many years on various boats and motors without apparent ill effects. By using the sail(s) I keep engine revs lower than otherwise and consequently am not overheating or asking too much of my diesel.
i see way too many boats motoring and missing fine sails in favorable conditions ,but this is a worthwhile technique to perfect and can do much to ease a bash to windward and create a feasible option .

...................Love you all.........mike.................................. ........

[Richard5]

What's your oil pressure? Answer at specific engine RPMs. I suspect heel is not the problem if you experience loss of oil pressure.

I am finding it hard to believe that even a 30* heel, if held constant +/- would yield an acceleration sufficient to overcome even 10 PSI oil pressure. I fly piston and radial engines. I go inverted without inverted oil system as long as I hold at least 1 g. And that's not difficult. Either I'm missing something or like I said, heel is not the problem. Perhaps heel becomes the symptom of the real problem, ie, blockage.

[Talbot]

Racing motorcycles used to use a dry sump and special oil delivery to cope with the problem of the engine being different angles etc. I have never understood why this system is not used on marine engines.

[SailFastTri]

Originally Posted by Talbot

Racing motorcycles used to use a dry sump and special oil delivery to cope with the problem of the engine being different angles etc. I have never understood why this system is not used on marine engines.

Sorry for the thread drift but why would that be needed on a bike where the leaning keeps the centrifugal forces more or less in balance with gravity? In other words, it's always nearly level inside the engine (with reference to the engine pan).

OTOH, a 4-wheeled vehicle being pushed hard in a sweeping turn has the centrifugal forces throwing the oil to one side of the pan. So the question is, how long can this be tolerated by the engine, and to what degree, as this is more equivalent to the leaning of a sailboat.

You have the same issues with acceleration in a dragster, or off road vehicles that climb and descend steep grades.

I think there is a spec for maximum angle of tilt (for continuous operation) for each engine design. It should be in the manual but if not, there is someone at the manufacturer who can get the info. Perhaps in a separate installation guide?

[Richard5]

Originally Posted by mrohr

I dunno, but find motor sailing is a neat solution to getting upwind when pressed for time ,esp. against steep chop in a seaway.I keep heel to minimum by use of the traveler while keeping the main full and pulling.I keep oil topped up and will tack up wind as necessary.
My contessa is quite weatherly so if conditions and /or course are such that any heeling is generated beyond, say 10 degrees,I then have the circumstances that do not require the assistance of the iron beast below.
Have used this technique for many years on various boats and motors without apparent ill effects. By using the sail(s) I keep engine revs lower than otherwise and consequently am not overheating or asking too much of my diesel.
i see way too many boats motoring and missing fine sails in favorable conditions ,but this is a worthwhile technique to perfect and can do much to ease a bash to windward and create a feasible option .

...................Love you all.........mike.................................. ........

Please elucidate how the main is pulling when bashing through chop to windward while motoring? Is it just a manner of how you said it? What am I missing?

All I can gather is you induce heel which reduces rolling moment.

Love to you too, Mike.

[barnakiel]

I never had this issue. The book says how many degrees fixed list the engine will accept but in the seaway the boat moves about, the oil sloshes in the sump and the engine remains lubricated.

Sure thing I do not sail her on the ear.

b.

[Richard5]

Originally Posted by SailFastTri

Sorry for the thread drift but why would that be needed on a bike where the leaning keeps the centrifugal forces more or less in balance with gravity? In other words, it's always nearly level inside the engine (with reference to the engine pan).

OTOH, a 4-wheeled vehicle being pushed hard in a sweeping turn has the centrifugal forces throwing the oil to one side of the pan. So the question is, how long can this be tolerated by the engine, and to what degree, as this is more equivalent to the leaning of a sailboat.

You have the same issues with acceleration in a dragster, or off road vehicles that climb and descend steep grades.

I think there is a spec for maximum angle of tilt (for continuous operation) for each engine design. It should be in the manual but if not, there is someone at the manufacturer who can get the info. Perhaps in a separate installation guide?

Have you ever visually followed the journals in a motor? Due to the orifice size there isn't any sloshing. As most of the oil is not in the pan, as a bike rocks swiftly through the corners, left and right, the oil is restricted from washing the engine. Café racers notably lay it down to one side or the other and are quick to the other side.

Therefore, I suspect loss of oil pressure is the answer for the OP and heel is not the culprit.

[SailFastTri]

Thanks Richard5, no I haven't. So is it different in a marine diesel?

[skipmac]

Originally Posted by Richard5

Please elucidate how the main is pulling when bashing through chop to windward while motoring? Is it just a manner of how you said it? What am I missing?

All I can gather is you induce heel which reduces rolling moment.

Love to you too, Mike.

Perhaps you are assuming you are using the main going dead to windward? Motorsailing upwind is not dead upwind but tacking upwind but at a much closer angle than you could achieve under sail alone. Depending on the boat I can point 10-20 degrees closer to the wind under main and motor so get there a lot faster. Just trim the main as close in as possible, run the engine at a fast idle and adjust course based on keeping the main full.

Works great. Uses very little fuel and you suffer much less bashing/crashing/heeling than under sail alone.

[Dockhead]

Originally Posted by barnakiel

I never had this issue. The book says how many degrees fixed list the engine will accept but in the seaway the boat moves about, the oil sloshes in the sump and the engine remains lubricated.

Sure thing I do not sail her on the ear.

b.

Unless your engine is splash lubricated, sloshing oil in the sump is not doing anything good for your lubrication. If the boat is heeled and besides that pitching in a seaway, you can easily uncover the pickup for the oil pump, which will then ingest air, and this is very bad for your engine. Oil foaming is also bad.

Sailboat engines really ought to have dry sumps. Then we wouldn't worry about this at all. As it is, nothing good will come from running the engine while heeled. I did this exactly one time -- on a night x-channel, trying to keep speed up not to miss my tide, and oil got thrown up through the breather into the intake tract and caused lots of problems. I was not heeling anything like 30 degrees, either -- it was more like 10 to 15 degrees, but in a fairly rough sea. Since then, I have never run the main engine if there is any significant heel, especially in rougher conditions.

[Dockhead]

Originally Posted by skipmac

Perhaps you are assuming you are using the main going dead to windward? Motorsailing upwind is not dead upwind but tacking upwind but at a much closer angle than you could achieve under sail alone. Depending on the boat I can point 10-20 degrees closer to the wind under main and motor so get there a lot faster. Just trim the main as close in as possible, run the engine at a fast idle and adjust course based on keeping the main full.

Works great. Uses very little fuel and you suffer much less bashing/crashing/heeling than under sail alone.

+1

Very useful technique. On my boat works best with mainsail alone, with the headsails put away.

[barnakiel]

Originally Posted by Dockhead

Unless your engine is splash lubricated, (...)

MD7, no idea how it is lubricated but we never hear any complaint.

I remember reading a VP publication where they said it is OK to motor sail in rough conditions but avoid continuous fixed heel. I have read a similar leaflet from Bukh, Bukh gave the better max continuous angle figure.

PS Our block is a tractor engine and I did see tractors go up and down steep hills working. They bump and lurch too, and quite a lot - possibly in a manner very similar to a sailboat.

b.

[mrohr]

Originally Posted by Richard5

Please elucidate how the main is pulling when bashing through chop to windward while motoring? Is it just a manner of how you said it? What am I missing?

All I can gather is you induce heel which reduces rolling moment.

Love to you too, Mike.

i do not drive (bash) directly into a serious chop, but attack it at a angle that keep will keep the main full and drawing.I also consider the comfort of any crew and whether
I'm generating a lot of spray and water over the decks ,way more comfortable than pounding into it and probably surely faster too. Depending on wave period, boat speed and angle to the seas and waterline length, there surely is an angle and speed ( the 2 variables that you can control) that will make this work for almost any boat, but believe a fine entry helps.
With main up and pulling (not flogging) you are ready to get sailing with motor off as soon as there is a wind shift or circumstances allow a course change.
Try it on your boat when conditions warrant and your boat will tell you when you have it right, and the admiral will have her confidence restored.
This is not rocket science or voodoo but just avoid the hobby horsing angles that rob speed and create many undesirable effects. I'm not saying this is a panacea for every possible situation ,nor is it my preferred method of getting about and around the frequent wind against the current issues and of course shallow waters.

It is also a marvelous way to win races while the rest of the fleet is floundering!

[JPA Cate]

Hi, everyone,

Dockhead is exactly right on this one. We sailed in loose company with some friends who used their engine a lot on the way from Coff's Hbr to Noumea. When they got in, the engine required a rebuild, and I'm quite sure would not have, had they not spent so much time with it heeled so the oil pickup was out of the oil frequently, for days.

Ann