Monday, June 12, 2017

Exxon Valdez Redux

There are basically two things to do with an old Porsche 911 like mine; maybe three, if you are of a certain mindset. They are: drive it, or fix it. The third would be to hoist it up onto a pedestal and show it exclusively, if it is rare for some reason, but this option is of no interest to me - mostly I want to drive it. A Porsche that is only a pedestal show car is one that equates to a collection of funky shoes, or an assortment of antique bowling balls, or other chachkas on people's shelves that they occasionally drag out into the light. Once a 911 reaches 'display-only' status, it then has become a flexible euphemism for a car, and woe is it.

There are other ways to experience woe, though. In my previous post below I pointed out that my car was running badly, because the fuel injection was confused for some baffling reason. That has been resolved and the car runs quite well, if not 100% perfectly. It will get there eventually.

Never mind that, now something on top of the engine is spraying oil, and I do not mean that a minor seepage is present. Splattering all over is what I mean. Grrr. Naturally this escaping oil is way at the back of the engine compartment, where no normal human can reach. The engine must come out. I just put the damn engine back into the car. Grrr.  I'm going through about one litre of oil per 160 kms (or about 1 qt per 100 miles). The problem looks like bad oil cooler seals.

Also see my post: "The Triangle of Death"

Seepage in this area is common, but it was dry here when the car last ran . . .
Keeping the car neat and tidy, and doing things to it to improve it in any way can be fun, and I do this. My car was built in 1973, although it is a '74 model. So, it's over half-way through its 44th year now. Parts wear out, parts break; you fix it and this is to be expected and is normal at such an age. However, this oil episode is not actually fun since it interrupts the driving of the car too much.

And, too much complaining, sorry. I should add that the car's valves have never been quieter, due to a good, engine-out-of-the-car adjustment. Along with the replacement of a rocker arm and other bits that needed retirement. Now all you really hear is the modest hissing of the cam chains, but if you wrinkle your brow you can notice a faint ticking telling you (me) that the valves are not too tight, either. 

Usually leakage in the "Triangle of Death" doesn't spray up onto the cooling shroud.
I'll write more as more happens. At this moment, the engine will come out of the car in a few days. While the oil leakage is being addressed, the oil thermostat will also be  tested to see if it is functioning properly. That job is easy once the thermostat is removed - you plop it into hot water along with an accurate thermometer to see when it opens and closes. The engine has been running hotter than I want it to do, and the thermostat might be at fault.

Update:  The engine did not actually overheat, but heated in an erratic way. Upon testing, the internal oil thermostat does appear to be at fault, and it is being replaced with a known good unit, or it will be rebuilt. See also my remarks in the comments below.

New oil seals got put on the oil cooler, and everything else back there. 

However, it's an old car, so there is no part at all on it that is totally above suspicion. Each drive is an adventure . . .  Nevertheless, all air-cooled cars are advancing in value. Maybe I should consider passing this car on and getting a new toy.

Like certain others below, this post does not reach a conclusion that satisfies me, or you probably, but rather some puzzles are left unsolved. It's the name of the game when keeping a classic car going, but it still solidly remains fun to drive.


Anonymous said...

Hi, excellent post, What year is your porsche? what is the exactly issue? engine overheating? Thanks for sharing.. Car finder

J911 said...

Thanks for the comment and questions. Basically there were two issues, one was oil leakage - which has been resolved; the crankcase breather hose was the culprit - and the second was temperature. It turned out that the internal oil thermostat was behaving erratically. It was too slow to respond to temperature changes. This might have been caused by a 'varnish' build-up that caused the sliding parts to be sticky. Or, something else. Anyway, at the moment the thermostat will be replaced with a known good unit, or rebuilt, whichever is most efficient. The engine did not overheat; it was just not heating normally. The car is a '74, but the engine is a rebuilt '75 with the usual upgrades.