Going over my manual for the 2013 Hatz genset (sold by Robin-Subaru)  HATZ 1B30 diesel BA_1B_EN_43380210.pdf
 I find this in the Fuel & Oil section

Winter fuel
When outside temperatures drop below 0°C, use winter fuel or mix in petroleum in advance:
Lowest ambient temperature at start [°C] Percentage of petroleum [%] for Summer fuel
 0 to -10         20%
-10 to -15      30%
-15 to -20      50%

So I don't mind mixing up some DIY winter fuel, but wanted to run this by this august community.
We're forecast for low 20°F ( -5°C ) next week  and I wonder about using the same mix in the 6/1 listeroid too ?
 

yesterday, my pump would not stay running, the Motor Protector circuit kept shutting it off after 20 seconds. I tried cleaning the filter, and running the outlet into a bucket, minimal backpressure, and it would still shut off. I really did not like the idea of having to repair a bum system in the rain, Rain. Clouds. Generator. Pump always worked on the other 3Kw generator (Listeroid - Metro) But the new generator - won't run the pump. Something about the PF of the pump, and the lightweight rotor of the alternator. The Subaru/Hatz diesel genset is rated 3.3Kw peak, 3Kw cont. But it's so lightweight (my old st-5 alternator weighs more than the new genset) I seldom run it at more than 2.5Kw charging batteries,
Goes to show that sometimes small is too small. With no other loads or battery charging going on, I can barely run a 1/2 hp pump off a 3Kw genset. What a pain that Power Factor can be. I guess the motor protector circuit did not like something in the power quality and shut the pump down.
The inverter qualifies it fine, but the motor protector cuts the pump off

rare screenshot with it running before shutoff  Combox screen capture

So, last 2 days, I've noticed some extra movement in the flex joints in the ex pipe and the valve cover stud is flailing around more.  All the bolts seemed tight, but a real close inspection showed movement between the upper frame and lower frame (not a motor mount) .  I pulled the bolt, and found a couple munged threads.
 It was a 7/16 coarse thread, grade 5 bolt, and a couple threads had deformed allowing movement. The nut looks OK, but it's hard to see inside it!
I went to the local store that claims to be a hardware store, and was only able to get some old dusty grade 5 fine thread bolts & nuts.  Tomorrow, I go to the big city (Ukiah) to get some real hardware (structural bolts with extended nuts).
 But the question of the day is ,  what should I get, Coarse or Fine ?
 I understand that coarse thread are "tougher to strip" but fine threads  leave more meat in the bolt for stronger bolt.

For listeroid applications, what should I search for ?  I also believe I should stay with grade 5, being less brittle than 8.  Or should I count on the steel frame absorbing shock and not matter about the brittleness ?

  Because of the web in the steel I frames, I can't get any larger than 7/16 bolts without the head and nut hitting the web.  I had to grind down washers to get them to fit.
 layup:
engine bolts to upper frame 
upper frame bolts to steel sleepers 
steel sleepers clamped to anchors in floor 

This morning, after about a 60 minute run at moderate load (2Kw, 6/1) as I was walking back to shut it down, I hear a new clank happening from 300' coming from the engine, at  about every 15 sec or so.  Very metallic and loud.  I got the the electric controls and shut the load (battery charging) down, and gave it about another minute to cool a bit, then shut the fuel lever off.   After I removed the load, I didn't hear the clank anymore and during spin down, I heard nothing unusual. Temps were fine, oil was full the day before. and a brief inspection and rocking the flywheels back and forth afterwards, revealed nothing.
 A short phone call to Tom (Thank you Tom) and his suggestion was loose gib key/flywheel.    I took a 2nd look at them, and the shaft collars are tight, keys look tight, and could not get anything to wiggle.    I'll pull the belt off and inspect the driving side flywheel again, but if it all looks good, what would the next step be to do?    I'm going to look inside the crankcase later today (had NRCS/USDA inspectors over this AM and couldn't get into it then)
 
 What does detonation sound like on 6/1's ?  It could have been that?  I've got a fair amount of fluffy carbon blowing out the pipe, but the exhaust looks pretty clean burning. Burning Red Diesel with a 100:1 2 stroke in it. I cleaned some crud off the injector less than a dozen hours ago.   It was not making the sound on every stroke, just 15, 20 sec intervals.

Baffled (Mike)

6/1 and a ST-5 @ 1500 feet elevation.   Just a little bit of overkill, but I have hit the limit on my feed wires & 20a breakers.

To be able to charge flat out at 2800 watts (240VAC) , and have a bit of headroom for a load starting up,  What size
wires and breakers should I change to ?  I'm thinking 10 ga, & 25A breakers ?  I'm sure the ST-5 can load the 6/1 too far
and would want the breakers to pop before then.

 So, I guess 3/8" bolts are insufficient to anchor my frame to the other frame.  While they lasted 50 hours, the replacement lasted 5 minutes.   To avoid having to pull the engine off it's frame, and then take the lower frame out and drill the I beams from their backsides, I'm looking for some some sort of drill, chuck, gearhead, 90deg air drive drill motor, something, that I can drill in place, up to 7/16" .   The rail width on the I beam is not large enough to get 1/2" bolts in, but I think 7/16 would do it.   

Any opinions if 3/8" is too small to hold the load, did I get a couple of duds ?   Would 7/16 be enough   to hold the frame (not the crankcase) of a 6/1

 So, the listeroid is staying, but I'm thinking I need a more conventional genset my better half can manage if I'm away and she wants to dry her hair or something.   I'm looking at the 3000W or 4500w, 3600 RPM Subaru/Robin gensets with a Hatz diesel as the prime mover. (  Hatz  1B30 & Hatz 1B40 )  Any red flags on these critters ? (air cooled, electric start, ~80db) can't find out if they are CS or glow plug for cold weather ?

So, I have a yard full of small engine this and that, and the diesel tractor, and the listeroid.   I use mobile 1 in my street vehicles, and know that the additive package in diesel oil is not good for cat convertors, but what about using diesel oil, in all the small engines and just stock one flavor of juice?