View Full Version : TR2/3/3A TR3 Timing Chain

12-21-2008, 07:50 PM
Initially I had planned to go ahead and replace the timing chain, sprockets, and tensioner on the 59 TR3 while I had the front end apart, figuring I'd rather spend an extra $100 now rather than have to take everything apart in the future. However, reading though the various threads here leads me to believe the quality of the replacement parts is not all that great, and I might be better off with the stock parts if they're in decent condition. Is that still the general concensus?


A visual inspection of the sprockets seems to show them to be in good shape, to my eye at least. They aren't "sharktoothed" or hooked. I added several thumbnails to my TR3 page -- www.woundedduc.net/TR3 (https://www.woundedduc.net/TR3) -- that you can click on to see much larger, more detailed photos.

The manual details measuring the chain by placing a straightedge between the timing gears and measuring the "deflection", noting it should be less than .4". What exactly are they measuring? Are they talking deflection as in pushing and pulling the chain fore and aft (towards the engine block and away from it)?

Thanks in advance.

12-21-2008, 09:15 PM

I'm doing the same, at least for the sprockets. No reason I can see to change them. The chain & tensioner though are getting replaced. Not positive, but I believe the deflection is what you see taken up by the tensioner, it would be the measured sag from the straight edge.


Don Elliott
12-21-2008, 09:53 PM
In 1990 I replaced the timing chain (I can't say if it needed to be changed) with 80,250 miles on it from new. This new timing chain has now been driven a little more than another 100,000 miles in 18 years. My sprockets and cam + can bearings are all the original ones from 1958.

But I had to change the timing tensioner about every 40,000 miles. So change that now and about 40,000 miles from now, change it again and have a look at your sprockets and chain again at that time.