Lister Engines > Listeroid Engines

Twin...SLOW SLOW speed....?

(1/3) > >>

Powdermonkey:
Folks- As a test, I removed my governor spring from my external linkage on the 30/2.  Under load, and "at speed", I'm running right about 800 rpm IIRC.

With the governor spring removed, that engine idled down to 20 turns in 7 seconds.  I could actually count the gib rotation on the mainshaft. 

So...about 200-250 rpm.  Quite slow. 

And that got me thinking:  On REALLY cold nights down here in FLA, could I run my 30/2 overnight at ~ 250 rpm, just to keep my cooling water from freezing?  By calculations, I'd use about 0.08 gallons/hour...or less (no load) at 200-250 rpm.   

The engine has an oil pump, which largely lubricates the mains.  Splash oiling for the rest of it.  So...my only real question is "lubrication".  Will ~ 250 rpm provide adequate lubrication to this 30/2?

Anybody got "real world" knowledge on this?

mike90045:
Somebody, in times past, made a crankcase cover door of plexiglass, to observe the activity while running.  instant oil mist was the reported result ( as I recall )  at normal RMM's the dipper slings oil everywhere, up to the piston grudgen pin, cam bearings... everywhere.    I doubt that can happen at slow RPM's and you could have an oil related failure.   
 And without sufficient heat, the piston & head will carbon up

veggie:

As mike suggested, the issue may be carbon buildup if you don't have enough cylinder head heat.
So.... find a way to build heat.
Do you use active cooling or heat-syphon?
A small12 volt circulating pump in the cooling circuit could overcome resistance caused by the addition of an inline thermostat. (Maybe 180f)
Many of us have modified the cooling water outlet flange at the cylinder heat to accept an automotive type thermostat.
Also, add a little load to the engine at that low speed. In fact, load it up as much as possible. Perhaps an alternator to charge the battery that powers the circulating pump plus some additional light bulbs until the engine is sufficiently loaded.
Then you may make enough heat to prevent carbon buildup.

veggie

Powdermonkey:
Veggie- Many thanks.  The engine is thermosyphon cooled.  I "could" pinch down the ~ 2 feet of rubber hose transition I've got going up into the tank.  That would provide some level of restriction.  I guess I could also run a bypass with a thermostat in the bypass.  I could also see how the thermosyphon works at low speed.  If I can bring the head temperature up to ~ 150F...that might do the trick. 

Hugh Conway:
@Powder
I don't know how your cooling system is set up. Tank or rad. If a rad, just throw in some anti-freeze, acts as a corrosion inhibitor too.
 If tank cooled, it will take too much antifreeze to be economically feasible. Also, a drain valve on the lower cooling outlet would allow you to easily drain the coolant out during freezing weather if it is only water that you want to use.
I am in Canada, my 6/1 lives outside and is used daily in winter for charging batteries. I use an old cast iron house radiator for cooling and a 50/50 antifreeze mix. Works for me.
Cheers,
Hugh.
BTW, I once removed the inspection door while running at very low speed. I can tell you that oil does get flung about quite a bit, even at low RPM............took me hours to get cleaned up!

Navigation

[0] Message Index

[#] Next page

Go to full version