Q – My 1976 912E has a number of issues and I think I need professional help.   I enjoy working on the car, it has over 300,000 miles on it and I enjoy driving it just as much as my newer Carrera.   Here’s the deal.   The sunroof will not shut all the way.   I have replaced the cables, cleaned the tracks, lubricated the motor, adjusted it until I am blue in the face, and still it won’t close.   That’s the first issue.

The next problem is my oil temperature.   When the engine is fully warmed up, I can’t drive it too far without the oil temp getting to ¾ up on the gauge and I am worried about burning the engine up.   The engine is a “crate motor” purchased from the left coast and I had it installed a couple years ago at a local shop.   It has no thermostat so I do not think that could be the problem.   I have checked and set the timing, set fuel mix and I am out of ideas.

The next issue is a lack of power.   I have had another 912E and it ran much better than this one.   Having checked everything that I know how, I need help.   Brad

A – As a professional, I may be offer you the help you need for the car, but you may need another kind of professional help for the passion that you feel for this particular model and the fact that you enjoy working on it. I sympathize. I too have been criticized for my taste in cars and my fascination with fixing them.   So call us both crazy.

For problem one, the one part you do not mention is the transmission, not the one that drives the car, the one that engages the sunroof cables to the sunroof motor.   That little bugger has an internal clutch and when it fails, the sunroof will not close all the way.   It takes a greater amount of torque to close the roof compared to opening it.   Try this.   Can you shut the roof using the tool that the factory provides? If so, and this is going to hurt, a new transmission is about $500.00 and you might need one.   If you or anyone can tell me how dismantle and repair one, I would really like to know, otherwise Porsche is the only way to go.

On problem two, oil temp is controlled by the thermostat mechanism and oil cooler working together.   When your thermostat was removed, did they also remove the directional flaps?   If so, you should pay that shop a visit and ask them to kindly reinstall them for you.   Years ago, when I was young and ignorant, I believed that thermostats were unnecessary and added complexity for no value.   Now, with a better grasp of the engineering involved, I never suggest that a thermostat system be eliminated. Not only will the oil cooler not receive the air flow it needs, the engine will take forever to warm up, This causes excess wear, bogging on acceleration and poor fuel economy.

For problem three, short of having a dyno where you can measure fuel mixture under loaded conditions, I strongly suggest that you install a wide band OXS sensor to monitor fuel mixture.   Your engine may be getting lean at highway speeds which can spell disaster to your valves and rings.   For a proper diagnosis of this issue, you really do need professional help!   More on this topic next month.   MC

CategoryMasterCylinder, MC912

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