That’s Jacked: How to lift with care and avoid the smoky burnout no one wants
Michael Kelly writes: I recently bought a 1974 Lotus Europa. When it comes time to work on it, what are safe points to pick it up using a Rotary two-post asymmetrical lift?
Jacking up any vintage car is something to be done carefully. Many cars originally had tire-changing jack points inset in the sides of the rocker panels. Whether using the original jack or a lift, it’s always safer to lift from the front and rear subframes. Lifting the car from them can be disastrous if they’re rusty.
How best to lift a fiberglass-bodied car like the Lotus has its own challenges. It’s difficult to reach the steel lift points with the arms of a lift, but it’s easy with a jack and stands. You can slide a long-reach low-rise floor jack under the Europa’s “front box” (the extension to the frame that holds the front suspension) and then put jack stands under the ends of the box. Similarly, you can jack up the rear of the car by putting a floor jack under the transaxle. Note that the factory manual says to support the car on jack pads placed in the corners of the fiberglass floor directly behind the front wheels and in front of the rears, as the fiberglass is stiffer in those corners (do NOT lift the car in the middle of the fiberglass floor!). Initially I was queasy about raising mine on a mid-rise lift that way, but I do it and have had no issues.
Dan Buck writes: I have a 1998 BMW 740iL with 198,000 miles on it and no significant engine work except replacement of the rear crankcase vent valve in an effort to stop a smoking problem that has me stumped. The car was running fine with no error codes and then one day began blowing white smoke out the tailpipe. This diminished after the car ran for a few minutes, then almost quit completely. Then, while driving at around 35 mph, a huge cloud of thick smoke poured out the back for about 10 seconds, then stopped. The car ran fine. For several days, it did this. After a handful of these incidents, the car started to run rough and the check engine light came on. My mechanic took the car for the weekend and experienced the same scenario. His solution was to replace the rear crankcase vent valve and swap the BMW synthetic oil with a thicker conventional oil. It didn’t work. He now suggests that the valve seals should be replaced. I’m suspicious of this because the smoking started all at once rather than gradually. What is going on?
The sudden smoking you describe is textbook for the oil separator valve (OSV), so I would suspect that first. Like a positive crankcase ventilation (PCV) valve, the OSV sends fumes from the crankcase to be burned in the engine, but it also separates moisture from the oil. There’s a diaphragm and three hoses. Things can fail in different ways: The hoses can crack, resulting in vacuum leaks and lean running conditions, and a torn diaphragm will let oil get past it and into the intake manifold, which sounds like what’s happening. As the system fails, moisture and oil mix, creating something that looks like yellow snot that can freeze in cold weather, send oil where it’s not supposed to be (like into the valve cover or cylinders), and cause major damage. I recommend you replace the OSV and every hose leading to it, clean out any yellow snot and oil from related passages (including the intake manifold), use correct weight oil, drive the car a few hundred miles, and see what it does.
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Rob Siegel has been writing the column The Hack Mechanic™ for BMW CCA Roundel magazine for 34 years and is the author of five automotive books. His new book, Resurrecting Bertha: Buying back our wedding car after 26 years in storage, is available on Amazon, as are his other books, like Ran When Parked. You can order personally inscribed copies here.
