Join Date: Apr 2006
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rconn, the A4 was built from an industrial low-compression low-rpm engine that was designed to pretty much run reliably "forever" with routine maintenance.
Gasoline is supposed to explode. Most fuels are supposed to explode. The only danger is when you are sloppy with the fuel and it explodes OUTside of the engine.
So you check things over once in a while. Replace fuel hoses every 5 years or so with new alcohol-resistant ones because "real" gasoline is hard to find these days. Make sure everything is clean and tight. And because it has a carburetor and carbs need to be overhauled every 5 years or so also (because of varnish and clogging as well as adjustment) you also overhaul the carb if it hasn't been.
And yes, install a blower designed for use on boats and get real religious about running the blower for 5 minutes before you ever ever start the engine.
The fumes and explosions aren't a real issue, but every year there are thousands of accidents on the highway because people can't bother to put air in their tires, so they overheat and blowout. For THOSE people, an A4 would be a problem.
Moyer Marine is The Ultimate Source for things A4. If the carb has been overhauled and the ignition gets routine care, it should run forever. Of course old spark ignition systems means points, coil, condensor, etc. also are expected to be replaced from time to time, so even if your engine runs perfectly, you might want to get a set of ignition spares and pack them away so they will be on hand when and if you need them.
Diesels don't have these problems, no. But they have their own problems, like a stinky exhaust and problems with fuel contamination and growth. Ask any diesel owner if they've ever heard of someone having a fuel problem, air in the fuel, a diesel stink...Sure, it is harder to make diesel blow up but that's not impossible either. "Fuel air bombs" aka "hypobaric weapons" use diesel fuel because it can explode very very nicely.
Make friends with your A4, it really is a simple system and with routine care will work very nicely.