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TR2/3/3A Checking if Timing Chain is Installed Correctly

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DornTRoriginal

DornTRoriginal

Jedi Hopeful
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I am going back through the engine rebuild I did 4 to 5 years ago, at the time I was a bit uncertain about the timing chain installation. I followed the service manual and I used a degree wheel plus I used a picture of the old assembly but the bottom line is I am not at all certain if I got the chain correctly installed. I am pretty sure I am close but not feeling real confident. I am thinking now would be a good time to re check and make sure the timing chain is installed correctly or not. My thought is I am at a point where it is less complicated to take things apart rather than find out its wrong when I am trying to start the engine and everything in the engine bay is completely installed.

My question is, is it possible to check if the timing is correct without removing the front cowl and Radiator to get access to see if the timing gears and the alignment to the punch marks and Keyway is correct? If there is a way it would be a big time saver. Thanks for the help! This problem is keeping me awake at night!

Engine Bay 01.26.2018.jpgEngine Bay 2 01.26.2018.jpgI need Help.jpg
 
I think you should be able to get a rough idea by removing the valve cover; set the #1 piston at TDC on the firing stroke then look at the valves on the opposing cylinder (not sure which one that is on a TR3) there should be one that is at TDC with both valves partly open; if they're evenly open then it's timed correctly. This assumes that you have a stock cam that is symmetrical and that the valve lash is set correctly.
 
That's the basic idea; assuming you have a stock (or symmetrical) camshaft. You can get a more accurate idea by first setting the valve lash on #4 (which is the opposing cylinder) to .040 (exact number not important but must be equal) and then measuring the lash with #1 turned to TDC compression. If the lash is equal (or just slightly larger on the intake), the valve timing is correct.
 
It's actually in one of the books, not my invention. TR4 workshop manual, maybe. And I forgot to mention, when turning #1 to TDC compression, it is important to only turn the crankshaft forward, stopping right on the mark. If you go past the mark, you have to back up by 1/4 turn or so (or go forward two full turns) to come up on the mark again. If you turn backwards to get to the mark, the slack in the timing chain will screw up your timing measurement.
 
Thank you! Lash means valve clearance measurement?
 
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