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TR2/3/3A Dynamic timing value

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J

John_Progess

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I am trying to start my rebuilt 60 TR 3A engine for the first time. I have it statically timed at 4 deg. before TDC. My book says the vacuum advance should be 8 deg. BTDC and max advance should be 15 deg. BTDC. I should then check the timing at about 1000 rpm at about 12 deg. BTDC and the max timing at about 3400 rpm should be about 27 deg. BTDC. Is my thinking correct? Thanks and have a good day!
 
You might mention what distributor you have (5 digit number, begins with a '4') and have a look at it on here:

https://www.starchak.ca/tech/pdfs/lucas.pdf

If the weights move freely in the distributor then static timing may be close enough to get it running well and final tweaks can be done based on how it runs on the road.

I always go back and check the total advance at high RPM just to be sure nothing is amiss.

All the books and charts are (in my opinion) just a starting point as engine condition, fuel, altitude and other factors will effect what is best for your engine.
 
If everything was done correct at TDC and the rotor pointed at number 1 push rod tube and your are not 180 off, then leave the distributor loose put a little starter fluid in and push the distributor away from the engine toward the fender just a little at a time and see if the engine will at least pop off. These engines are also very cold blooded and need some choke. If your choke is undone, I take and manually pull the choke arms down and put a ÂĽ inch U shaped piece of sheet metal bent like a horse shoe or something and put that between the adjusting nut and the jet to hold the choke out. It should at least pop, if not check the basics.
 
OK! Got the engine running right off the bat. Sounds good, idles good but a little high at 1000 rpm and the idle adjuster screws are not touching the stops so I may have to adjust the throttle discs to let the shafts close more. I set the timing to about 12 deg BTDC at 1000 rpm. The temperature was steady at 185 deg. and the oil pressure was 60 lbs. The distributor is a DM2 and the number I think is a 40488A. The weights move freely. It is always a happy day when the engine first starts after a complete rebuild telling you that you probably did everything right! Now to put the body on the frame and get started attaching the sheet metal. Thanks and have a good day!
 
I'm with you on the thrill of getting it started. In my case I had done some nifty things to the engine so I had do considerable tweaking to get it too run. Also found that the advance suction tube was not installed properly by yr's truly so that has given me a fit (story to be told in another thread, sigh). I finally got that fixed so I will be giving it another run in test soon so we'll see what happens.
Anyhow, all that to say congratulations.

Cheers, Dick
 
Fantastic, it does feel good. Sometimes I think I put myself through the rebuild just for that moment. Anyways, it was suggested to me to run the engine @ 1500 to 2000 rpm for 20 minutes to let the moving parts set into each other. I just went through it; you could check out that thread with the way back machine on the forum. I would guess you might be advanced in the trimming and that is why your idle is high. These engines usually do not have much adjustment on underside of the idle. With the screws just touching and no vacuum leaks and even with the correct trimming you will be at probably 600 rpm or not running at all and a new engine is usually tight and will not idle down very good.
 
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