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ljibis ljibis is offline
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Join Date: May 2007
Posts: 26
Originally posted by randytrish

When I was having CIS problems I advanced the timing from 5ATDC to 8. This helped with hot starting. I reset the timing back to 5 to see if that had any affect on the oil temp and it hasn't. The car seemed to run and start better at 8 degrees. I don't know what you mean by the mechanical timing.
The mechanical timing refers to the relationship between the crank/layshaft and the cams. It basically determines at what point in the cycle the cams open the intake and exhaust valves. It is set when the engine is being built up by rotating the engine and using a dial gauge. Has your car ever been rebuilt at all, or do you know a time that the heads would have been removed?

On the 930 I mentioned previously, the mechanical timing was mis-set during a top-end rebuild. The valves were opening at slightly the wrong time leading to poor starting and running and really high oil temperatures, none of which were easy to compensate for with changes to the ignition and fueling. After spending days looking into other causes, it was determined that there had to be something off mechanically, which there was.

I'm not saying that this is your issue at all - there's no way for anyone here to say much for sure - but if your engine was apart at some point it would be one area to look into. Everything has to be set right for these engines to perform correctly.

Originally posted by randytrish

In doing searches and who knows how many posts the internal thermostat kept popping up. I am not looking forward to doing an engine drop to get to this thing.
Can it be replaced without an engine drop?
I don't think so, but I don't know for certain. Hopefully someone else will chime in on that.

If you can't get it without a drop, you could test it (per the method from my first post) and see if it's working. Then if you need to look into the mechanical timing the engine will already be out of the car.

Or you could just drive it...something worse might happen, but it may be just fine. As was stated before, it's still not at the "damn hot" stage (240-250). That said, I'd agree that it's running on the hot side. Good luck.
1977 Porsche 911S
Guards Red/Cork, no sunroof, no flares!
Old 06-21-2007, 02:42 PM
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