Mark Maras

@jalexquijano A spark tester is an excellent idea and cheap too.

There's something that ZedHead mentioned a while back as a possibility and that's a bad oil ring in #4. We've covered most, if not all, of the easy things. How does one check to see if an oil ring is bad without pulling a piston? The only thing I can think of is a borescope?

So, not enough miles driven to determine oil usage?

What about oil usage? Miles per quart or how often do you top it up?

The numbers look OK. Lets try heading down another path momentarily. Something I don't remember discussing in the past is oil usage. How many miles do you drive before it needs a quart of oil and are there any oil leaks?

I don't like to compression test a hot engine because I don't like to remove spark plugs from a hot engine. However if the plugs come out easily it's better to test the engine when it's warm.

Remove the coil wire, remove the spark plug wires and spark plugs, get comfortable in the seat and turn the engine over (wide open throttle) with the starter until you see oil pressure on the gauge. It shouldn't take long. Then proceed with the test.

That should work just fine. Good luck and I said earlier, build some oil pressure with the starter, plugs out, first.

But first recheck the compression with the throttle wide open.

The only thing I can add is I remove the plugs and turn the engine over until I see oil pressure, then test. When I didn't start with oil pressure #1 would read low the first time and higher on the second test. Good luck.

To each his own, I guess. It reminds me of the Excalibur from the sixties.

Gas pedal? The best one for heel and toeing.

Do you know if he held the throttle wide open during the tests?

@jalexquijano This info may add another piece to the puzzle.

I'd like to see the results from another compression test. I'm beginning to think it may be a bad oil ring as suggested by Zed Head.

Keep the stereo, get rid of the car.

in the Portland area we have an ON Point Credit Union ad on tv that has a beautiful blue 280. It only shows the hood and windshield but it's unmistakable.

Is the black crud on #4 dry or oily and does it smell like fuel when you remove it?

@jalexquijano. I remember discussing changing the valve seals several times. Did they ever get replaced?

Kinda reminds me of the E Type hearse in the movie Harold and Maude.

But, as I recall, the compression was good on all cylinders. Correct me if I'm wrong @jalexquijano.

I understand the logic in having the fan clutch heat actuated BUT I think it would have been an improvement to have the fan clutch only actuated when the vehicle slowed below 10 mph.. As Zed Head stated "The fan only matters at low (or no) vehicle speed.

I actually had two old Chevys back in the day. A 39 long bed pick-up and a 49 deluxe coupe. As I recall the 49 had a push button starter and the 39 had a starter pedal that you stepped on to mimic a starter solenoid.

Our daughter just got a new Nissan. She showed me all the bells and whistles it had which included "push button start". The look on her face, when I told her my 49 Chevy had push button start was priceless.

As I understand it, 14.7:1 is the ideal ratio but everything I've seen and heard says a gas engine runs much stronger and COOLER with the mixture somewhere in the 12.5:1 to 13.2:1 area.