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1989 Mercruiser 3.0L Retrofit EST Timing?

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cwork

New member
I realize there are other timing forum posts out there but none of them answer my question clearly so here goes. I have a 1989 Mercruiser 3.0L (0C528921) that I upgraded from the original breaker point system to the Delco Remy Voyager EST. Question I have is what does the new timing get set to? The specs on the flame arrestor cover indicates 6 degrees BTDC. Do I adjust back to the 6 degrees BTDC in base timing mode or normal idle (not in base timing mode) at 750 rpm. Or is there a new set point all together?

I have scoured the Internet for hours to no avail. Any help would be appreciated. Thanks!
 
Thanks for this Bt Doctor. So it appears that I need to use the initial timing connector (base timing mode) to adjust the distributor to provide 0 degrees BTDC. Would it make a difference that my engine is pre-1990? I have read somewhere that it can make a difference as the engines were made differently. Also, can I use a standard timing light to check to make sure the timing is 24 degrees at 4,000 rpm? My timing indicator at the balancer doesn’t read up this high. Is there any way to extend it or is eyeballing it good enough?

Thanks again.
 
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cwork said:
I realize there are other timing forum posts out there but none of them answer my question clearly so here goes. I have a 1989 Mercruiser 3.0L (0C528921) that I upgraded from the original breaker point system to the Delco Remy Voyager EST. Question I have is what does the new timing get set to? The specs on the flame arrestor cover indicates 6 degrees BTDC. Do I adjust back to the 6 degrees BTDC in base timing mode or normal idle (not in base timing mode) at 750 rpm. Or is there a new set point all together?

I have scoured the Internet for hours to no avail. Any help would be appreciated. Thanks!
Click to expand...
You are switching ignition systems only, and have not changed any internal engine components, correct?
If so, your engine will be happy with the same ignition advance curve that it saw previously.
(this means the progressive and the total advance per engine RPM)

cwork said:
Thanks for this Bt Doctor. So it appears that I need to use the initial timing connector (base timing mode) to adjust the distributor to provide 0 degrees BTDC. Would it make a difference that my engine is pre-1990? I have read somewhere that it can make a difference as the engines were made differently. Also, can I use a standard timing light to check to make sure the timing is 24 degrees at 4,000 rpm? My timing indicator at the balancer doesn’t read up this high. Is there any way to extend it or is eyeballing it good enough?
Never eye ball ignition advance! It is far too critical to roll the dice on.
Find the diameter of the harmonic balancer, and apply the correct timing decal for that diameter, and strobe against it.
Click to expand...

Again, unless you've made internal changes that would require an altered ignition advance, I would set things up so that the engine sees the same ignition advance that it was happy with previously.

Keep in mind that BASE or Initial advance is BASE or Initial advance all day long.
We fire up on BASE and we idle on BASE, and that's it.

Much more importantly will be the progressive advance and the total advance and at what RPM each is occurring.
There is no substitute for that!


.
 
You can use a "timing tape" with your 'classic' timing light...

personally, I don't waste time with the 'timing plugs' on the EST distributors - I just set them up for full advance and typically live with the resulting initial timing...
 
makomark said:
You can use a "timing tape" with your 'classic' timing light...

personally, I don't waste time with the 'timing plugs' on the EST distributors - I just set them up for full advance and typically live with the resulting initial timing...
Click to expand...

Smart move! I agree.
 
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