The Gods Of Machinery And Entropy have apparently decided that this is the perfect time for my truck to yield to their capricious whims. I don’t believe it’s the truck they’re after. It’s hours of my life they want, and they very carefully selected just the right hours to maximize my displeasure with the whole affair. The money I’m spending was earned by dealing with my least favored current client and the unnecessary emergencies he creates, and the repair is going to eat a few hundred bucks out of my wallet and a long, full day out of my life. The rotten bastards. They were waiting for this. I know they were.
The failure is one of those that doesn’t disable the vehicle. Instead, it would just leave someone who doesn’t know any better thinking that it’s normal enough for older vehicles to demand a quart of oil every thousand miles and so dutifully pouring it in at about that rate. That someone who doesn’t know any better, though, would learn a very expensive lesson about cascading failures. This particular failure that can be fixed with just a relatively inexpensive gasket set when caught early can destroy the catalytic converter and at least one cylinder head if not addressed early. Left to go even longer it would eventually disable the engine.
The inexplicable part of it is that I’ve succumbed to superstition despite having argued against this particular stupid-stition for years. Some folks with just enough knowledge to be dangerous have given rise to the myth that this specific failure is due to the different thermal expansion rates of dissimilar metals, between which is a gasket — the idiot theory is that the different rates of expansion place stress upon that gasket which is clamped between them and that stress eventually breaks it. It just ain’t so. What’s really happening is that the bolts that hold those dissimilar metals and the gasket all together are just about as long as the holes into which they’re threaded, and though the bolts are all pretty damn close to equal in length there’s some greater deviation in the depths of the holes. Where the bolts bottom in the holes they fail to provide sufficient clamping force to prevent the gasket from moving in response to the pressure differential across it, creating a tearing force between the points where the gasket cannot move and where it does move. The fix, the only fix necessary, is to install slightly shorter bolts when replacing that gasket. I know this. I sat down and did the math to disprove the dissimilar expansion rate bullshit. (Fortunately it’s pretty simple math that doesn’t get beyond my limited ability.)
But because the myth exists there are enterprising souls about who manufacture and sell an aluminum piece to replace the steel piece that does not in fact cause any problem at all if the bolts are not bottomed in their holes. And I just bought one of them despite knowing that I do not need it.
The Gods Of Machinery And Entropy are surely laughing their intangible asses off right now.
I suppose I could make up some bullshit about how the thick aluminum replacement piece, being much more rigid than the steel it replaces, will more evenly distribute that wonderful clamping force and so presumably will increase the lifetime of the gasket. I actually like that idea — being a lazy bastard I’ll put in 150% of the money and effort this time if it’ll save me from doing it a second time. But I’ve no reason to suspect that just using shorter bolts alone wouldn’t leave me with a gasket very likely to outlive the rest of the engine so I’m kinda back in the realm of supposition, if not superstition. Maybe I could say that if I ever indulge the fantasy of installing a supercharger I won’t have to install the new piece then, which fits my lazy bastard way of being just fine. But I know that doubling the horsepower would just expose the next weak link, then the next one, then the next one, so I’m pretty unlikely to spend several thousand dollars just so I can be silly in between spending more money upgrading weak links. Never mind that I’ve already got the most expensive piece of it, the transmission, in place. I know I am given to occasional fits of irrational self indulgence so it made sense to just do it.
Hmmm… That’s it. I know I’m given to occasional fits of irrational self indulgence and might one day get around to supercharging the thing, so I just autopiloted the decision because it actually makes a certain kind of sense. The pilot just napped through the flight until the autopilot shut off and had to ask, “Hey, which airport are we landing at?”.
And now the Gods Of Machinery And Entropy are begging me to stop because their intangible ribs hurt from laughing so hard. They haven’t seen anything this funny since George W tried to ride a Segway.