1.You appears you are no longer promoting the EarthX batteries.Is there something about them that those of us that use the battery should be concerned about?

2. I'm confused about what grade of gas to use for the 130. It appears that you are advocating 100LL or 89 octane mogas.

In a previous post you said that the 130 was not picky and any gas would work. I have been using 86 mogas with no issues. Should I switch to 89?  And, I understand you want marvel mystery oil to be used if running 100LL. Is this correct?


Glenn Davis

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I'm sure Jan will chime in soon, but in the meantime thought I'd share our findings.  

In the beginning, we only used 100LL with Pennzoil 0W-20 synthetic blend engine oil.   The blend oil was to help suspend lead.  The synthetic blend oil became unavailable after around 30 engine hours, so we had to switch to a full synthetic.  Because we still primarily use 100LL, Jan recommended we begin adding Marvel Mystery oil to the fuel tanks, and we have ever since.

We now sometimes add 5 gallons of regular unleaded Mogas to each tank, as well as the Marvel Mystery oil, and then top off with 100LL.   Since our fuel is now usually a blended 100LL and Mogas, we typically just use 86 octane.   A friends Honda Engine Service Manual says to use regular unleaded, but does not specify an octane level.   We have yet to take compression readings, but the prop pull feels the same as new. 

I too look forward to Jans reply.   Always best to hear it from the manufacturer if possible.  

1. We don't trust them as much as we do the sealed lead acid due to some failing. The scary part is you never know when it will fail. Look for bulging batteries or erratic operation, such as, not accepting charge, not closing the battery contactor, etc. 

2. There is no significant monetary saving using anything other than the best car gas available. The main reason is that lower octane fuel also loses its octane rating faster than higher octane fuel. Because airplanes don't generally fly often, a stable fuel is highly desirable. If using 100LL you must use Marvel Mystery Oil (1 ounce per 10 gallons). 

Jan, what is the purpose of the Marvel with respect to engine operation?  Just curious - thanks ... Dave!

To maintain compression by preventing lead from locking up the piston compression ring. 

To you find the mystery oil is more effective to prevent lead build up than Decalin?



Decalin is not useful at all.  

Jan, you state categorically that Decalin is not useful at all.

Another expert (Rotax, British Columbia) says this:


Decalin Run-Up is "acknowledged" in SI-912-016 sec 5.2. This is as close approval as Rotax will go as they have not done any official testing themselves but instead are relying on field results. A huge fleet (hundreds of engines with over 150,000hrs of flight time) of Rotax 9 series engines runs on avgas with Run-up and it does work and it does not harm the engine.


On what do you base your assertion that Decalin is useless?

I don't want to beat this to death but since I'm about to start adding the Marvel mystery oil (MMO) I want to be sure I use the correct dosage.

You said 1oz/10gl. and MMO FAQ recommends 4oz/10gl.


Glenn, that was a typo, if you follow what the Marvel bottle says that is in line with our recommendation. 

You had previously sold us on the use of EarthX batteries, and we have been using them ever since.   We have two EarthX 680C batteries.  Not knowing when a battery might suddenly fail can be said for any battery, that's why our batteries are closely monitored, and we have two.  What other battery there will keep the engine running as long after the alternator fails?  


What ratio of MMO do you use in the fuel?



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