Timing Question

[Sunken Ship]

With the engine running I connect the +12v wire from the shunt and the timing does not change at all based on ear and the location of the mark on the harmonic balancer. I set timing to the only notch on the timing chain cover w/shunt connected to +12v. Motor bump starts, but pops when I rev it sharply. Changed the ICM.

Any ideas? 1999 4.3GL-PWTR

Thanks

 

[Dave-R]

In the Volvo Must have technical section , there is a timing procedure. After you install the shunt it puts the engine in the base timing mode. I don't have an advance timing light, so I have to make a mark 8 deg BTDC. This is about 5/8" to the left of your timing mark on the harmonic balancer. After you tighten the distributor, check the timing again. If it's good, pull the shunt. Read and print the procedure, it works. Dave-R

 

[Sunken Ship]

Reading the late Don's post he said it "may" reduce RPMs - referencing the moment +12v is applied to the shunt.

If I match the notch on the timing chain cover and the notch on the harmonic balancer then I am at TDC or 0 degrees, which is what I am trying to achieve with 12v+ applied. My procedure is:

1. Start and warm-up engine;
2. connect +12v to shunt while engine is running;
3. turn distributor until the two notches (timing chain cover and harmonic balancer) align; then
4. tighten distributor bolt.