Bob,
The calculator and instructions were very helpful. Thanks
You did some great work with your system. A most impressive installation.
The issue am having is twofold.
1] I can't find data on my various insulators for in/lb load ratings in order to use the calculator so I had to estimate.
2] I plan to run the engine at 375 rpm constantly charging batteries. A speed of 375 rpm gives me an excitation frequency of 3.125 hz and the majority of the isolators I have access to all have a natural frequency of 7hz to 8hz.

All the guides I have studied recommend that isolators should have natural frequency of approx. 0.5 that of the excitation frequency in order to force them into the proper performance zone..

Natural Frequency vs. Excitation Frequency:
For effective vibration isolation, the natural frequency of the mounting system (where the engine is attached) should be significantly lower than the engine's excitation frequency.
Frequency Ratio:
Aim for a frequency ratio (excitation frequency / natural frequency) greater than 1.5 to 2, to ensure the vibration isolation system is working in the vibration reduction area.

So I have a mismatch problem for my low speed application.

Trial and error with soft mounts is a lot of work when mounting a 6/1, so I am still considering a solid mount with a 1600 lb base block as recommend by Lister.

I also invite other users to pipe in here and let us know what worked for you ( whether a solid mound or a resilient soft mount) What worked for you ?

I also fully concur that mounting a 6/1 on a massive block of concrete is the easiest and time tested approach.  If I didn't need to originally operate our 6/1 inside our attached garage in a housing development where stealth and safety were critical, that's likely what I would have done. 

With regard to the 6/1 engine design, Lister was pretty ignorant relative to machine design engineering knowledge and application today.  Lister compensated for their knowledge shortcomings by designing massive engines mounted on massive concrete.  I felt that unbalancing the fly wheels to compensate for an unbalanced piston arrangement wasn't the best approach...or in more simple-minded terms, two wrongs don't make a right...  In fact, I dynamically balanced our 6/1 fly wheels in a similar fashion that car wheels are balanced today...with the objective of reducing vibration and increasing component life.  And with component life also in mind, I didn't want the forces created by the 6/1 unbalanced piston arrangement to remain locked within the engine by concrete either.  So, with all this in mind, being a mechanical engineer and given our original location requirement, a resilient engine mount provided the required solution and was relatively easy for me to successfully accomplish.

Anyhow, that's what I did and my rationale for doing it.  As detailed in the previously provided links, I had to put the isolators in series (i.e., a two tier, 8 total isolator design) to achieve the required isolation performance given the specifications of the available isolators.  So just know that it is always possible to design a proper isolation stand by using some combination of isolators in series or in parallel.  But yeah, an isolation stand does require math and much more thought than pouring lots of concrete.  For better or worse, that's how my mind works and what I have done my entire life.  If you want a headache, give this a read sometime...

https://www.borstengineeringconstruction.com/AIAA-74381-139.pdf

All the best however you proceed!

Cheers,
Bob

Duplicate post Deleted

https://www.borstengineeringconstruction.com/Sample_Isolation_Stand_Design.pdf

I don't have any experience with running with WVO, only SVO.  I don't have any experience with injecting straight water water either.  Running propane simply results in more complete combustion which results in less residual carbon formation.  Furthermore, a by-product of propane combustion is a significant amount of water vapor.  So in addition to getting more complete combustion with the associated increase in mechanical horsepower, one also continuously steam cleans the combustion chamber when running propane.  So I suppose one could say that one is BOTH minimizing the formation of carbon and also quickly removing any carbon that may result.  This really isn't new knowledge as propane combustion chemistry has been known and taught in mechanical engineering design courses for many years

I think most of us 6/1 natural gas and propane users just rely on the existing mechanical governor to maintain a constant engine RPM.  As long as there is an adequate percentage of diesel or SVO still being throttled by the mechanical governor, and as long as the natural gas or propane flow rate is kept constant (typically using a gas regulator), the mechanical governor will handle typical load variances and maintain a constant RPM quite well.  Since you can't run a high percentage of propane anyhow, this is good approach for propane.  If you wanted to push the near 100% boundary with natural gas, I could see how using a small constant flow of diesel or SVO and throttling the natural gas might have some advantages.

Similar setup to Carl and can burn either natural gas or propane as indicated.  Primary fuel is SVO and mostly burn a low level of propane to eliminate carbon buildup and any associated maintenance.  Use a vacuum switch to close solenoid and stop flow as safety precaution should the engine shutdown.  Will be 10 years of operation this September.

http://mbryner.fatcow.com/listerenginegallery/main.php?g2_itemId=351

I have been running my 6/1 on SVO in my attached garage for almost 10 years:

http://listerenginegallery.com/main.php?g2_itemId=351

The engine is of course mounted on a resilient engine stand.  The exhaust goes through a wall thimble into an underground concrete tank for noiseless decompression and then runs about 100 feet underground in perforated plastic pipe and eventually surfaces without any sound/smoke.  The crankcase check valve is vented to the outside as well.  There are smoke and carbon monoxide detectors in the garage and the emergency shutdown control system will shut the down the engine by dumping carbon dioxide into the engine intake if these detectors get tripped (or if the engine over-speeds, over-temps, over-vibrates, or the oil level gets too low).

Bob B.

Exactly so Quinn and I believe we had a very nice post at the time detailing this analysis and proper TRB setup.  It is a well established engineering fact that using TRBs appropriate for the application which are properly setup will significantly out live plain bearings.  A Lister tech from the 1950s might be a good historian, but would be far from an expert relative to proper engine design.  Has there ever been a TRB failure reported?

Bob B.