The project started innocently enough. One of the CV boots on the Porsche 911T was torn and had sent grease all over the heat exchanger and everything else. Like many ailments to the early 911, a keen sense of smell is critical to early detection. With the pre-war VW heating system in these cars, you tend to develop a sense of what your engine smells like under normal circumstances. This is useful because by the time you actually see the flames shooting through the grill on the rear decklid, it is often too late. I detected burning grease and shut things down. Satisfied that it was the boot, I nursed the car home.
Someday, I hope to hear a satisfactory explanation for this design, which is common to so many different vehicles from this era and well beyond. A complex and expensive flexible joint which has high speed rotating parts, which is under the car exposed to dirt rocks, etc, and which must remain lubricated, is protected by a $6 (probably 50 cents back then) rubber boot fastened by metal or hard plastic hose clamps. Anyone?……anyone?…..Bueller?…
The next day, I ordered some boots. A CV boot for an early Porsche 911 costs about $6, and I had ordered 4 just to be safe, and to get to the $20 free shipping limit. $6 and a few hours should have me back on the road. The next weekend I launched my assault. I got the rear of the car up on jackstands, and spent a good while cleaning up the mess. I had boots, tools, a can of grease to repack the axle, and I was all set. Except, I wasn’t. While cleaning up I discover that the driver’s side heat exchanger has several holes and the outer housing is basically detached from the exhaust header. This would explain the rattling sound heard on occasion. Although work continues on the cv joints, thoughts have already shifted to heat exchangers.
I do want to maintain heat in this car, so headers are eliminated. The next day, I search the forums, Ebay, and Pelican. I find a pair of heat exchangers in good shape from a fellow owner about 130 miles away. I decide that the budget will not withstand new SSI units, to I drive a few hours and come back fairly pleased with the parts, and fairly displeased with the magnitude of the unplanned expenditure. I also remember that I have a pair of heater control valves form the prior year’s Hershey swap meet. Better tackle them now as well.
During the following week, I remove the heat exchangers, and notice that one of the oil tubes is leaking. Well, with the heat exchangers out, now is the time to address them, and since we are tackling oil leaks, I need a pair of valve cover gaskets as well. So I order the items to arrive before the weekend. That weekend I dig in again. I quickly discover that a couple of the heater control valve nuts are rusty and seized. I leave them soaking overnight in penetrant. Of course, these two nuts are in the most inaccessible locations, so the next day it takes heat and a couple hours of contortionist positioning to finally get them off. I celebrate like I won the lottery.
During the next week, I finally get things back together. $800 and almost 3 weeks later, the $6 cv boot with 2 hours of labor is successfully replaced. Saturday afternoon I go for a drive. The glorious aroma of hot metal and a little paint seeps into the cabin when I open the heater control valve. Having your engine smell just right as you fly down a country road…..priceless.