After making timing adjustments I marked the cam wheels for future reference. Note above-Intake @ 108 and Exhaust@ 107 and arrows showing which way the "cam" was turned. Notice the black line on the wheel of the intake side. This was in line with the notch on the nut before adjusting and now it is moved CW slightly. I made these marks as examples of what's taking place with the position of the parts involved before and after cam timing adjustments.
This pic above shows the position of the cam lobes when the piston is at TDC on the compression stroke. This is the cam position used for checking the belt tension.
Since I don't have the mechanical tensioning tool (I guess it's no longer in production) I decided to try my own "harmonic tensioning" system. Above- Korg tuner.
The manual states to "tune" the belts to 110Hz or an "A".....well, after a lot of trial and error I was able to get both belts tensioned to 110Hz. I then checked their tension the "old" way by twisting the belt between the rollers to see if it twisted 45 degrees and the "between the cam wheels" push test to get about 4mm flex! Both these tests proved that the tuning method worked out. Would I take the time to "harmonic" tension them next time?....maybe, we'll see. Note: I included the chart with the notes and Hz above to show the tight reading of 140Hz that should be used when checking cam timing.
The tuner and a rubber coated rod that I tried to use to tap the belts, but I found that just flicking them with my finger worked best. Another note: make sure it's really quite in the shop or you'll never get a true reading. AND have the tuner's mic postioned down near the layshaft pulley where the shop manual shows the Matheis tester being used.
After making timing adjustments I marked the cam wheels for future reference. Note above-Intake @ 108 and Exhaust@ 107 and arrows showing which way the "cam" was turned. Notice the black line on the wheel of the intake side. This was in line with the notch on the nut before adjusting and now it is moved CW slightly. I made these marks as examples of what's taking place with the position of the parts involved before and after cam timing adjustments.
This pic above shows the position of the cam lobes when the piston is at TDC on the compression stroke. This is the cam position used for checking the belt tension.
Since I don't have the mechanical tensioning tool (I guess it's no longer in production) I decided to try my own "harmonic tensioning" system. Above- Korg tuner.
The manual states to "tune" the belts to 110Hz or an "A".....well, after a lot of trial and error I was able to get both belts tensioned to 110Hz. I then checked their tension the "old" way by twisting the belt between the rollers to see if it twisted 45 degrees and the "between the cam wheels" push test to get about 4mm flex! Both these tests proved that the tuning method worked out. Would I take the time to "harmonic" tension them next time?....maybe, we'll see. Note: I included the chart with the notes and Hz above to show the tight reading of 140Hz that should be used when checking cam timing.
The tuner and a rubber coated rod that I tried to use to tap the belts, but I found that just flicking them with my finger worked best. Another note: make sure it's really quite in the shop or you'll never get a true reading. AND have the tuner's mic postioned down near the layshaft pulley where the shop manual shows the Matheis tester being used.
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