Been trying to get my friend's car running for the last month. He removes parts then I come over and look at them to see whatever there is to see. His engine was running really crappy on his way home from out of town and he barely made it home.
Starting off, we replaced the distributors cap and rotor.
With the age of the engine the most obvious thing was that his timing chain had jumped a tooth.
I checked that scenario out with the best methods that I could come up with and decided that was not the problem. I had him remove one of the rocker arm covers so we can see if there was anything obviously wrong. There was. The rocker arm should contact the top of the valve and one of them didn't. The gap between the rocker arm and the valve was .096". That's fairly close to 3/32 of an inch.
Just a week and a half beforehand on a kick, I bought a boroscope. It was close to 50 bucks and has a 16 ft cable so you can stick the camera down inside things like walls or vents or inside the engine.
What perfect timing to have one of these in hand. The camera image shows up via Wi-Fi on your cell phone. Anyway peering down inside one of the oil return holes in the head you can see the lifter valley and I could see the cam lobes. Here's what I saw
In the first two images you can see the bright shiny bare metal look of two of the cam lobes. In the third image you can see a cam lobe that is shiny on the edges but has a carbon varnish to the center of the lobe. That lobe is how they should look in an old engine.
The shiny lobes barely open the valve because they are totally worn out.
I readjusted all of the rocker arms and he put the covers back on.
The engine purred to life and the idle was relatively good considering the cam and lifters are trash. Gently raising the RPMs, the engine has soft backfires. That's because the exhaust valve doesn't open far enough to let the exhaust gases out.
This is literally been a month-long journey checking in probing his engine when I've had the opportunity.
His dad bought this car new in 1980 and he inherited it. It's been garaged it's entire life and the paint is good the pinstripes still look like new. No rust on the body panels. The frame inside the engine bay and even on the underside is clean as a whistle.
I could see the despair in his eyes as he finally had to admit this car has finally died. Yesterday was his birthday and he turned 83. Not so good news for a birthday or Thanksgiving gift. Darn.