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| Joined: | 05-01-2005 |
| Location: | Minneapolis, Minnesota USA |
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Are both timing marks (110 & 115) on each pulley? As in, does the current 115 EX exhaust pulley also have a second, unused timing dot next to a 110 mark? If yes, then note that on the current front face of the exhaust pulley, there is a 115 EX, and a 110 'IN'. You can NOT time the exhaust cam by an 'IN' timing mark !! You'll bend valves.
Instead, follow the tooth the 110 IN timing mark is on to the back side of the pulley. There, on the back side of the same tooth, you will find the 110 EX timing mark you need. So changing the cam timing (for either cam) involves first removing the pulley, flipping it over front-to-back, and re-installing the pulley (torque the bolt to 25 lbs-ft). Then align the 110 EX mark on the exhaust pulley with the 110 IN mark on the intake pulley.
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All the above started in the middle of the procedure just to highlight what you need to accomplish. The correct first steps would be...
Set the crank to TDC with the cam pulley timing dots aligned on the imaginary centerline between the cams (ie, #1 at TDC).
Remove the timng belt. Not 'completely', but slide if off of the two cam pulleys and let if flop down out of the way.
Turn the crank back 90 degrees. Don't get too OCD precise about it, just an 'eyeball' 90 degrees. That puts all the pistons halfway down their bores, and well out of the way of the valves. With that done, you can now spin both cams willy-nilly as you work on them, and no valves will collide with anything.
When you're done 'flipping', align the "forward facing" cam timing marks "ON" the imaginary centerline between the two cams... 110 IN on the intake pulley with 110 EX on the exhaust pulley. If the timing marks align with one another, but are not on the imaginary centerline, then the cams are "NOT" correctly timed. Once you have the pulleys correctly timed...
Turn the crank back to TDC and align the auxiliary pulley, then re-install and tension the timing belt. Torque the tensioner retaining Nyloc nut to 25-30 lbs-ft.
The correct tension for the oem BLACK timing belt is 95 on a Burroughs BT-33-86J, or BT-33-73F tension gauge... or OTC 6673 tension gauge (same gauge carrying a corporate syster's brand). If you use an inexpensive (you get what you pay for) Krikit KR1, then set the tension to 52 on the KR1's "Pounds" scale.
If you install the Gates Racing Blue trapezoidal tooth belt (T104RB), then the tension should be 82-84 Burroughs, or 34-35 Krikit KR1. The Krikit's scale doesn't go that low, so you'll need to use the 'sharp points' of a caliper to scratch new marks below the end of the existing "Pounds" scale.
A proper Borroughs gauge is a worthwhile/ recommended investment if you're going to do your own mechanical work on your Jensen-Healey.
Regards,
Tim Engel