Good Customer Story For a Change!

[NCO]

Thought I'd post this one to remind everyone, myself included, that sometimes among the bloodthirsty mindless Walkers (reference to favorite show on AMC) there's a few good ones.

I'm actually lucky where I work in that our clientele is a pretty nice bunch of folks. We get the occasional jerk but I rarely have to deal with them personally and when I do encounter them, I just go get the boss and let him take care of things.

Last month a regular customer dropped off his 03 Malibu for a coolant leak. It has the 3.1L engine and those engines are notorious for intake manifold gasket leaks. That's where this one was leaking from, sure enough. This is probably a 3rd or 4th car for the gent, so he wasn't in a hurry.

He also wasn't in a hurry to get the leak fixed before he brought it in. When I removed the valve covers and upper and lower intakes, it looked like the Sludge Fairy had eaten a buffet of spoiled Ethiopian cuisine and taken a massive dump all over the place. In the end I billed him for about 7 hours (at $85/hour) for the repair and clean-up plus re-threading stripped bolt holes thanks to GM's love affair with cheap crappy aluminum. Plus the 3 oil changes I did back to back before releasing the car, just to make sure.

I ran into him yesterday on my way to lunch at a fine Southern cooking establishment around the corner that I frequent. I was standing off to the side and when he asked I told him I was waiting for Mrs. Patsy to serve up some of her most excellent fried tilapia and collard greens. I got my fresh hot tilapia and collards, with a side of cornbread of course, and he walked up behind me in line and paid for my lunch.



Moral of the story is this, the good ones are out there.

[Shalom]

Ugh. Thank you Dex-Cool.

Thank you also to the idiots at GM who decided that a plastic gasket was appropriate for a hi-temp application like this.

[Racket_Man]

Ugh. Thank you Dex-Cool.

Thank you also to the idiots at GM who decided that a plastic gasket was appropriate for a hi-temp application like this.

Yeah I will 2d that one only it cost me $2000 (for both lower intake manifold gaskets). IT seemed that era of GM cars had LOTS of builtin problems and repairs waiting to happen.

[EricKei]

RM - I do believe the relevant term is "Planned Obsolescence" ~_~

[iradney]

Moved to praising

[Chromatix]

Devil's advocate on head gaskets and coolant problems:

Head gaskets tend to warp and start leaking when the block overheats. At that point, you will start finding coolant in the oil, and vice versa, and excess oil in the cylinders. Coolant usually turns into sludge in the oil spaces, and oil in the cylinders will be noticeable as blue smoke in the exhaust.

Overheating tends to happen when the coolant circuit is compromised. This has several common causes - from a blocked radiator (tends to occur gradually, can be detected by comparing temperatures of different parts of the radiator), through a failed pump (many are belt driven, and the belt can break), to simply low water level (which can impede circulation since the pump has to work against a head).

The coolant itself is generally half water and half antifreeze. You can top up the system using just water in an emergency - it is the water that absorbs and carries heat, and the mixture has some tolerance for different proportions in any case. The most common antifreeze for coolant is ethylene glycol plus some anti-corrosion additives - for windscreen washing fluid it is more likely to be methanol. (Both of these are toxic if ingested.)

Dexcool is indeed ethylene glycol plus some specific and unusual anti-corrosion elements - it is dyed a different colour to identify these minor components. It is intended to require replacement less often than standard antifreeze types. Cars designed for Dexcool can use standard antifreeze, but then require the antifreeze replaced just as often as other cars.

Since the coolant circuit is a closed system, the main causes of low water levels there are leaks (which can be found by examining the ground before and after parking) and venting (pressure vents are fitted to prevent steam from bursting the pipes). One fault with some GM engines appears to be that the pressure vents were faulty, and could get stuck in the open position, effectively causing a small leak.

The combination of this small leak with plastic (nylon/silicone) gaskets on several parts of the coolant circuit, and an anti-corrosion component in the antifreeze which was known to weaken plastics, had the entirely predictable outcome of early gasket failure.

Apparently Honda and Toyota use a long-life antifreeze very similar to Dexcool, but *without* the component that attacks plastics. One might assume that they also use a different type of pressure vent that doesn't fail open so often.