Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Wet Sumping

I have been looking at the online X-Wedge owners manual, a bit more detailed than the workshop manual in places. It says this about the oil filters:

"The S&S® X-Wedge® engine requires a spin-on filter with an anti-drain back valve, rated at 10 microns. The S&S oil filter part numbers are 31- 4104 for Chrome and 31-4103 for Black. Filters for 1999-later Harley- Davidson® big twins (#63798-99A and 63731-99A) are also acceptable."

My M3W doesn't suffer from wet sumping and I use K&N oil filters, I assume they have an anti-drain back valve? In reply to Farmer Giles, the other S&S forums seem to think that the problem relates to the oil pump as well.

It also says:

"S&S recommends synthetic engine oil such as S&S Premium Synthetic 20W50. However a premium petroleum based engine oil such as S&S Heavy Duty 20W50 is acceptable"

I can’t imagine how MMC put different advice in their handbook to that given by the engine manufacturer?

Could it be because Morris Lubricants don't make a synthetic 20w50 motorcycle oil?

Bitsobrits/Stave, many thanks for your input on the design of the S&S engine, it is obvious I have no knowledge of it specifically and have zero specialist knowledge, I am nought but an old enthusiast for much mechanical who bought into the idea of owning Morgan as a retro vintage vehicle, without the cost of a real vintage car of similar performance, a vehicle which I could hopefully maintain with the simple tools I had to hand, and one on which was not dependant on on-board digital decision making.

From that which you typed Steve you seem to be a pretty hands on type of chap, and like Planenut seem to have arrived at the conclusion that possible variation in engineering manufacturing tolerances may be found in the machining of the oil pump internals, to the extent that some oil pumps may allow more oil to pass through the pump when at standstill as the combined result of gravity and perhaps the viscosity of oil used in the engine... ? As a theory that can work for me. (-:

As for the issue, it seems modern-day driver expectations do not align with engineering that may be thought of as old school, i.e. fitting taps to try to resolve the issue of "wet sumping"which as Jonny suggests may create an agro of antiques situation, I can go with that too, and could I then suggest that the electric M3W may well be a far more suitable option for some which seems likely to bypass all of the M3W engine related issues...? I guess if the sound of the V Twin is a key element to ownership, then there could be the possibility to add that electronically, perhaps sacrificing a little mileage range dependant on how much volume might be selected..? (-:

Getting back to the issue, you M3W types are not alone in having issues relative to lay up, the WWW is full of all sorts of folk having loads of issues caused by lack of use. For me the bottom line may well be that in general engines tend not to be designed to spend long periods of time standing unused, other than perhaps for specialist purposes such as standby power generating units which usually have means by which the oil pressure can be either created by an auxiliary electric oil pump, or manually pumped prior to pushing the start button. In the case of an emergency standby engine, expected to power up automatically and take load in a minimum amount of time, in which case it would rattle till oil pressure builds...! Not ideal for engine longevity but then lives could be dependant on the engines ability to take the zero oil pressure fire up..? Were I designing a standby engine I suspect I may not pick a design where the oil was held at high level, outside the engine and fed to it by gravity. With a wet sump it could at least splash feed some aspects of lubrication required in the initial stages of fire up..?

The idea of using thicker oil to minimise wet sumping seems to present possible risks for engine longevity.. One would hope that those who designed the engine would suggest the best possible lubricant for their engine design, all things considered..?

As hinted above, lots of other engine designs seem to have issues, even the German designers, famed for automotive engineering prowess and motor sport achievements over many years, seem to have quite a number of customers complaining over time, some engines self destructing, even at car park speeds..? I have noted where independent specialist engineers have researched and modified an engine design to "improve" upon aspects one particularly expensive engine, and have advised an change in lubricant once the engines reach higher mileages of circa 80k miles or more.

For sure the WWW is full of fake news, though before the WWW it was far less likely that without a fair bit of determination to carry out research, that anyone would be likely to discover the many variables in manufacturing processes which could affect the variation of performance across the output range of any manufacturer. These days it is al so very different with access to search engines to educate ones self on so very much..which can and I suspect does create issues for manufacturers, add fake news to that, and things can become complicated for those in search of reliable information.

Prior to replacing my last old air cooled 911 with an old but professionally restored +8 Morgan, I had the benefit of the internet resources of the then MSCCDG, GoMoG and subsequently the wonderful Morgan forum at the now defunked eMog, and thus came to understand having spent circa five years of internet study, I understood most if not all the likely ownership issues relative to Morgan ownership prior to buying one, all of which seems a tad excessive, I know. I bought into the idea of heritage, hand crafted and vintage aspects of design thus leading edge engineering expectations played no part in the purchase decision process, also my time spent reading of issues educated me as to the situation where many were created by those driven to experiment and modify their Morgans, which was appeared to be very much the Morganeers creed, at least up to the time when digital electronics complicated matters for the would-be home mechanic.

Apologies, I have rambled on a bit as is my habit, but hopefully you catch my drift...

My engine suffers quite badly from wet-sumping if left idle for more than a couple of days. Therefore, I was excited to try switching to mineral oil to see if it would resolve the situation. In a nutshell, I did and it didn't. No perceivable change in wet-sumping behaviour with mineral oil over synthetic as far as I can tell. The only advantage I now have is that I can see when I've wet-sumped due to my new clear vent line.

Very sorry to hear that Bunny. I guess that means that my purchase of 20 litres of bargain Motul V-Twin Fully Synthetic oil from you is a non starter then? ☹️

Bunny,

When you say your engine suffer quite badly from wet sumping, what are the symptoms? Have you drained the crankcase to see how much oil is actually in the sump before startup? With a clear vent line, I would think it normal to see a certain amount oil moving one direction or the other once the engine starts, but it may be just a few ounces, which in a 3/8" vent line could look like a lot.

In normal operation with a healthy engine, there will inevitably be many ounces (like maybe 1/2 to 1 quart/liter) of oil in the crankcase after only a few hours of shutdown due to all of the residual oil in the engine draining down to the lowest point, plus any of the hot, thin oil back flow through the oil pump into sump. Dry sump engines are never truly dry, only relatively so when compared to a wet sump engine.

If you are not pumping oil into your intake manifold and/or out the air cleaner on startup and the engine's not leaking when standing idle for a few days, then I would say there is nothing to worry about.

There is probably at least 2 Litres of oil in the sump and now I have a clear vent line I can track its progress! As you can see it is up above the steering rack now.



The engine has been standing for around a week without running. Fortunately the crank seals seem to be good and I'm not getting any leaks from the engine (front or back).

This is quite a high volume of oil to shift back to the tank so I think I'll adopt the manual drain method for the time being.

What happens when you just start it? Does the oil get spit up into the tank quickly? Or sucked back into the sump?