914-6 runs HOT - solved? Options

[767driver]

Hi guys,

Lurked here for a number of years and have finally landed a 914-6. It's a 1970 with it's numbers-matching case running a (stock?) 66mm crank and 86mm pistons for a displacement of 2.3L. It runs Solex cams and 40 Webers. It's only got about 600 miles since rebuild. So the engine is somewhat upgraded but nothing too wild.

When I drove it the 45 mostly-highway miles to my house I noticed it was getting a bit warm. The weather was about 60 degrees. The indicator on the factory oil temp gauge was reading about 3/4. The next day I took the car for a nice "getting acquainted" kind of run on mixed highway and country roads. After 25 minutes on the highway at 80 mph and about 3500 rpms it was getting really warm...almost touching the hashed red part of the hot end of the scale. I immediately went over to a buddy's shop and shot an IR thermometer at the rear of the oil cooler. Got temps of 220 or so at top of cooler and 250-260 at bottom. The cooler still has a Stoddard Porsche decal on it. I checked and the cooler is the $1335 German-made part. Oil quantity ok.

Now I know this is not enough motor to overload the factory oil cooling assuming everything is working correctly. I took the thermostat out of the car and performed the pot-of-hot-water-with-thermometer-trick and verified it opens and closes as it should. I guess the in-dash gauge could be wrong, but the IR thermometer seemed to confirm the high reading. All the tins appear to be in place. I have read the cylinder baffles can be installed upside down causing issues. And that the cylinders themselves can be installed upside down. I guess that new-ish oil cooler might be defective...that's an engine drop...right? Ignition timing, cam timing, fuel mixture need to be checked. And none of the cabin heating air tubes are on the car. The 2 supply ducts off either side of the engine cooling fan duct are capped. Is the fact that no fan air is going through the heat exchangers causing the one under the oil cooler to run hot enough to cause the high oil temps? ANSWER: YES

So...what have I forgotten or overlooked here. I had 2 VERY knowledgeable Porschephiles tell me that barring an oil cooler issue it is almost surely a hot bearing (youch!) making that kind of heat.

Any thoughts or ideas are appreciated.

1970 914-6
VIN 9140432125
Engine 6405400

[porbmw]

There are far more knowledgeable persons than I who have already weighed in on this.

However, there may be one other means of helping to lower engine heat...by increasing air flow...by using the two air deflectors that later models of 914s were supplied with...If I recall correctly, in around 73/74...affixed to the underside, one on each side of the underbody, just in front of the engine

[porschetub]

There are far more knowledgeable persons than I who have already weighed in on this.

However, there may be one other means of helping to lower engine heat...by increasing air flow...by using the two air deflectors that later models of 914s were supplied with...If I recall correctly, in around 73/74...affixed to the underside, one on each side of the underbody, just in front of the engine

Yea good point,I believe they really made a difference.
Not sure in this cause perhaps things are a little deeper (IMG:style_emoticons/default/sad.gif) .