Thursday, November 15, 2012

Unexpected Blessings

Occasionally, the celestial practical jokes department fails to get the memo that I am working on a VW and I squeeze some successes out before they notice...and lower the boom on me. Yesterday, I took the day off and, among several things, spent some quality time with old Ferdinand.

Again, I was impressed at what complete condition the old buzzard is in, despite his wounds and neglect. That engine, while I doubt it has ever been cleaned, is certainly the most complete Type4 I've ever seen that hasn't been completely refurbed. My very limited goals for Ferdinand were simple: Test the Fuel Pressure Regulator, and put fresh gasoline through the fuel ring, hopefully cooking off much of the goop in the line.

To pull the regulator out, I clamped off the fuel return, got the hose off of the regulator and found that the regulator itself has a retaining nut that holds it in place against the engine tin, with the outlet on the forward facing side, pointing toward the fuel tank return. A 14mm open end wrench helped me take that off, and then I moved up top and discovered what a joy it was to work on that engine from the TOP, via the top engine hatch. I pulled the FPR off of the fuel ring, hooked it up with the fuel pump and hoses to recycle to the 1 gallon jerrycan and gave the pump some power.

Fuel came pouring out of the outlet just like it says in the workshop manual. Hooray. I rejoice because the FPR isn't gummed up, and when vacuum is applied (by me, and some clean hose) to the vacuum port, the diaphram in the FPR opens up and lets the fuel flow faster, just as designed.

Why would I be so surprised by these successes? Because I think the celestial practical jokes department is out to get me? No. Because the most common warning among all of the experts in aircooled engine-mongery  will offer is: expect the FPR to be a deader. From fuel gum, varnish, and failure to take the 5th.

Sidebar:


And this is when it hits me, that a barn find of this vintage might have been the easiest animal I could have purchased. This bus received its last fill up around February of 1998. At that time, it would have had MTBE in the fuel as the oxygenated ingredient to reduce knocking. Since then MTBE has been removed from USDM fuel in the mid-2000s and replaced with ethanol at percentages up to 10%. There has been a huge uptick in classic cars gagging on the new gas mix. The VW engine was never designed to run on the E10 goop, and the hotter mix makes the exhaust valves glow white-hot. But worst of all, the dang gas stratifies in the tank. You'd think for all of the extra alcohol in the fuel, that the contents wouldn't stratify, but it does.

So the water goes to the bottom and rusts out your fuel tank, the alcohol floats on top of that, and the gasoline (which is the least dense) floats on the top. And when this unholy brew is pumped into the fuel ring, the alcohol gets left behind forming into a gummy mess, because one of the things that is happened is that the ethanol is eating away at the insides of the fuel hoses which were not chemically engineered to take alcohol.

Result: clogged injectors, varnish galore, ruined FPR, and seven years bad karma. Or something. But bad juju for your fuel system. And there has been a lot of noise online about dealing with engines that burn the Bus to the ground because the fuel is literally eating the hose away under 28psi of pressure in the fuel ring. When you blow a hose, you spray gas all over a hot engine with a sparkler on top of it (the distributor) going ZAP! 8000x per minute at freeway speed. FWOOSH! Cooked Bus.

But the load of fuel in old Ferd' is 1998 vintage. It may smell like a petroleum cat-house at low tide, but it doesn't have any ethanol in it for which I need to light a candle (but not near the gas tank!) and say thanks. I only have to deal with the run of the mill-vintage varnish, which is pretty easily put back into solution with a liberal helping of carb cleaner, gum out, or other patent nostrums. And once it is off moving parts, we're in a lot better shape for keeping it that way, not by avoiding E10 gas (impossible) but by keeping fuel stabilizer in the tank regularly, and don't let the old boy sit.

But there is still that unholy brew in the tank to be drained. And a replacement tank that needs to be prepared to take its place. More on the procedure for that hamster dance next time.

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