lrsm2

Hoping i can get some ideas here. Recently purchased a 1975 911 sportomatic. Runs very hot, even after installing a front cooler. Oil pressure drops low as well. Cars mileage is relatively low (mid 70's) runs xlnt, no noises or other issues.One mechanic suggested engine cooler could be blocked from crumbling engine sound deadener pad, no real signs of debris with ALT out. Any ideas?
also, is it possible to replace windshield trim piece without removing windshield?

Peter Zimmermann

Isrm: How hot is "hot?" Does your new front cooler get hot to the touch? If yes, when oil starts to flow through it what does your dash temp gauge read? You might have a bad gauge...

Your "low pressure at idle" should not be a matter of concern, many 2.7 engines have the same issue.

Pete

john70t

Get to the source, and, qualify.....
Buy a Raytec remote lazer-thermometer(forgot the official name) and start up the engine from cold checking each cylinder head and exhaust manifold runner as it warms up. Equal=good.

The 75-77 2.7L supposedly had long-term heat problems because the thermactors(early version of cat) tended to keep heat in the engine compartment. These can independanty overheat from too many loose HC molecule vapors (misfire, too lean, way too rich). Again equal=good as long as the total is in spec.

Oil pressure senders are notorious for going inaccurate. My 70T registered 0psi at cold idle until I changed it. Then it showed 20psi. Be on the safe side though.

john70t

Suggestion: If you believe the oil cooler is clogged(and a big temp drop between the hoses shows up with the car sitting still and no airflow) then at the next oil change blow it out in reverse flow with 20(more?)lbs of air untill it flows good. Cheaper than buying new.

pjc

Isrm; keep the oil level as high as possible, remember the torque converter uses the engine oil. Don't run the car for long periods in high gear at low revs - these cars don't like it - factory recommendation is that if the temperature rises change down to produce higher revs. In the UK heat is not so much of a problem and we don't have the smog kit either - one change you can make is to change the 5 blade to a 11 blade fan - another is to modify the tinware, see Dempsey's book on rebuilding 911 engines. The book is written around the 2.7 engine and is helpful in this area. When hot, pressure is typically around 50 lb at 4,500 to 5,000 rpm - at idle the gauge may well appear to be bouncing on the stop but this again is prety typical. If all this fails it could be your oil system is not performing correctly - is the valve opening to allow oil to front cooler, when hot feel the flow and return pipes; have to assume the car's serviced regularly with correct filter etc.

PJC