Block heater fires are not that uncommon, we have had probably half a dozen threads on them over at the Powerstroke forum in the past year. The PSD heater is 1,000 watts, which makes for more current than on the Benz heaters.
Also 7.3 Superduty trucks (99-03) are in such demand that resale value is higher than Blue Book value most eveywhere, and they are easy to sell on top of it, no reason to torch one.

Add to that, if someone wants to get rid of one just park it on the street for a few nights, it'll disappear.

I'd say it's a pretty big stretch to say it was arson.

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Brian
87 300Dturbo 180K #14 head still running R-12 SOLD 12/2017
02 F350 Powerstroke 180K
05 Chevy Express 1 ton w/Royal Utility box 120K
08 Infiniti FX-35 40K
15 Golf Sportwagen TDI 35K
10 Sprinter 3500 chassis with a Class A Winnebago on it. 56K

My theory as a trade electrician is what I call "strand reduction". When a cord is improperly removed by pulling on the cord instead of the cap repeatedly (like what happens when you drive off with it plugged in) you begin to break or pull wire strands out where they are connected to the blades on the plug cap. Eventually when enough strands are no longer in contact with the blade you have a reduced area for current to flow (just like if you were using a tiny extension cord), which generates the heat which will melt the plug cap and eventually start burning, catching all the plastic around it, like the grill for example.

A very loose plug connection can build heat the same way when using a high amp draw device, so make sure those extension cords are good quality and tight fitting.

It is not the exposed copper on a worn cord that starts a fire so much as a loss of contact during current flow.

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Brian
87 300Dturbo 180K #14 head still running R-12 SOLD 12/2017
02 F350 Powerstroke 180K
05 Chevy Express 1 ton w/Royal Utility box 120K
08 Infiniti FX-35 40K
15 Golf Sportwagen TDI 35K
10 Sprinter 3500 chassis with a Class A Winnebago on it. 56K

x2

They're great trucks.

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

What happens when they're parked "on the street," as opposed to a driveway?
Read the guy's previous posts on the dieselstop. The pic and fuel line splicing problems he's posted scream POS/ill-cared for truck. Next, notice the studio-quality of the photo, (all @ 4:00 a.m. - yeah......riiiiight) as well as how the truck is outfitted/jacked-up to wear the chassis/suspension parts with oversized tires screams dogged out. Insurance would pay more (likely A LOT MORE) than that old POS truck would fetch, just as insurance pays astronomically more for old MB diesels than casual sales/trading them in.

My 7.3 hasn't burnt my Ford down in 8 years of use. If it did, I wouldn't have a studio set for pics. Blaming the block heater offhandedly may be bogus, regardless what the guy posted.

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'06 E320 CDI
'17 Corvette Stingray Vert

Reading that thread, your theory seems a big leap to me. People are offering him 1500 bucks for the burned up truck to rebuild it, plus, he discussed a wrapped up possibly damaged block heater cord

What you are calling a studio set looks like a flash picture from a pretty standard camera at night. I think you are jumping to a pretty out there conclusion.

If you read any of the collected threads from dozens of posted on these forums, a cursory glance will show you they are mostly about problems with the vehicle. If I apply the same logic you are applying, I could call most of the cars discussed on this forum POS vehicles, and worth burning for an insurance payout.

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