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Timing Cam and crankshaft

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Skip & Lynne

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How do I set the cam and crankshaft for top dead center. The new timing chain has no bright links and I seem to remember something about a specific number of links going on each side of the cam and crank gears but I don`t remember what they were or where the crank and cam gears were set. How do I set this up can anyone help. thanks Skip
 
Skip,
I personally would never rely on counting links or aligning marks to accurately set cam timing. Too many places for something to go wrong with parts variations & too hard to correct after the car is together.

Use the positive stop dead center location method. it will also tell you if the original damper timing marks are correct or how far off they are.

Degreeing in the cam is the only sure way to get it right the first time. True, it takes extra time & equipment, such as a degree wheel & a dial travel indicator, & maybe some new experiences, but it is certain. Look up camshaft installation, timing & degreeing on the internet & check it out. I can find some "how too's" if you need. If you find that the timing is not correct within a couple of degrees there are various remedies such as offset keys available.
D
 
Thanks Dave but I don`t think any of that will work. I have 2 degree wheels and dial indicators so setting the crank at TDC is no problem. The cam gear on the A/H 3000 engines is keyed to the cam and held with a single nut and lockplate so there is no way to use offset timing bushings. The A/H shop manual describes the bright link on the timing chain to be set with the timing marks on the cam and crank gears but there is no mark anywhere to line up the cam gear with and the diagram in the shop manual is vague at best. If I can find out how many chain links are supposed to be on the short side of the chain then I can set #1 piston at TDC and set the cam from that. The timing chain has a long and a short side with the long side going over the chain tensioner. I will give Vons Austin Healey a call in the morning, Scott who works there is pretty sharp on these things. Thanks Skip
 
Timing changes are made with offset keys, not bushings. The part in the cam slot is in a different location than the part in the gear slot. I guess that only racers who are after the last bit of performance actually care about a few degrees of cam timing error. The really serious guys use adjustable cam sprockets. Still wouldn't hurt to find out where it is. Check here to count the links;
https://www.team.net/html_arc/healeys/200112/msg00467.html
D
 
I talked with several people today and this is how they all say it`s done. With #1 piston at TDC ( I used a magnetic dial indicator) the timing mark on the crank gear is pointing straight down. Then take a felt tip marker and mark one link of the timing chain, count 13 links and mark another link so that there are 13 links between the marked links on one side and 16 links on the other side. Then one marked link goes on the crank gear mark and with the 13 links on the right side of the engine ( from the front view) the other marked link goes on the cam gear which should be pointing straight up. This means the cam and crank marks are 180 degrees apart one straight up and one straight down. This is almost backwards from any other engine I have ever built but hey go figure. Skip
 
S & L, I think it is a little simpler to indicate that there are 15 links dot-to-dot and it works OK-Fwiw---Keoke
 
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