U20 upper timing chain

[70MTRoadster]

As some of you may recall I posted recently that I had received a free 1969 2000 engine and 5 speed. Guy pulled it for an SR swap and gave it to me thinking the engine was frozen....too my glee, it was not. It sat for 35 plus years and the rings were frozen. Pulled the head, pulled the pistons and rods, cleaned them up and installed new Hastings rings from Dean. Honed the cylinders, reassembled, broke in at 2500 rpm for 20 minutes and 155 lbs. in all holes!

My question is this engine has 67,000 verified miles on it and the Evil L has about 1/16" grooves in it. I shimmed the tensioner as per the way it is done and now have just a barely audible ticking at start up with 65 lbs. oil pressure at idle; how much life do you guys think is left in this upper chain? I really don't want to tear her down any further, just throw her in my 1600 and drive her. I only get to drive maybe 500 miles a year up here in Bozeman, Montana anyways. Before my stroked 1600 roadster I owned 2 each 2000's and have longed for the thrill of the U20 at full song for many years.

Scott
70 2 litre stroker
68 510 wagon
72 510 4 door "gramma automatic"
72 510 4 door VG30/5sp. street racer

[Gregs672000]

Are you able to post a pic or two?

[Gregs672000]

I'm sure the best advice would be to replace the chains. However, I've never had one break; I've always understood that it was the L that broke off due to being cut, which I GUESS says something about the abuse the chain can take (?). But many others like JT could probably comment a lot more on what the chains tended to do. But something sure does happen... my original valve cover had been welded up when I got the car 34 years ago, and I've seen a cover on ebay that was welded too.

However, given what you've got into this motor (not much!) and the few miles (500) you plan to drive, I fully believe you could drive it and enjoy it for 6 YEARS before it's next oil change (based on miles of course, not time) and I'm pretty sure it would survive to at least ONE ... that's a long time, and I would be very very surprised to hear it blows up due to a timing chain breaking in those 6 years/3000 miles. What does the rest of the head and cam look like?

[70MTRoadster]

Cam looks excellent. I measured the head and cylinders and everything is standard, unmolested. I'll try and post a pic or maybe a video but bet they are too big for here.

IMG_0793.JPG

[70MTRoadster]

I make it a habit of writing the date and mileage on the oil filter. Last time the Stroker had its oil changed was back in 2014! I did the math and was shocked to find out I have only driven an average of 388 miles per year since. Winters, no driving at night due to deer on the road, and short spring/summers plus being involved in other things, sports not conducive to taking the roadster out contributed. Gotta get out more!!!

[SLOroadster]

Replacing the chains is the best option. However, I think you could cut the L off (place a rag below it, with a magnet to catch the metal filings) shim the tensioner and be fine. You don't even need to cut fully through the L, just cut it enough to be able to flex it back and forth and it will break off along the cut.

Will

[JT68]

If it has 67k on it, the chains are well past their prime. They are certainly a wearing item and there is no reasonable way to know when they will fail and come apart. Unless you actually disassemble the chain, visual inspection won't tell you much.

The L is a completely separate failure mode.

J