weird timing symptoms
#1
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Mercruiser 3.0 serial: D706324 EST Ignition (all new parts) Carb rebuilt. Starts on half a turn usually. Idles smooth, runs quietly.
My issue is that I am short about 800 rpm. I get on plane ok. I am propped correctly. I am also missing about 10mph on top end. I set the timing according to the proper method. It is right now at 0 Degrees BTDC (I think manual says I need 1 Degree BTDC). When I am on the jumper with switch bypassed, it doesn't sound any different than when it is on regular mode. Plus, when the jumper is removed, the timing still sits at 0 Degrees. It does advance to about 12 degrees when I am at about 2500 RPM. When at WOT I can't see the mark as I don't have an advance timing light.
I do believe that something is not right. The ignition EST module is brand new.
Ideas anyone?
My issue is that I am short about 800 rpm. I get on plane ok. I am propped correctly. I am also missing about 10mph on top end. I set the timing according to the proper method. It is right now at 0 Degrees BTDC (I think manual says I need 1 Degree BTDC). When I am on the jumper with switch bypassed, it doesn't sound any different than when it is on regular mode. Plus, when the jumper is removed, the timing still sits at 0 Degrees. It does advance to about 12 degrees when I am at about 2500 RPM. When at WOT I can't see the mark as I don't have an advance timing light.
I do believe that something is not right. The ignition EST module is brand new.
Ideas anyone?
#2
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From: On A Dirt Floor
What is the total supposed to be ?
Why was carb rebuilt and ign module replaced ?
I too rebuilt a carb and replaced module on a 3.0 the other year.so i remember some things..but it was a Volvo Penta so has the luxury of having a Holley 2bbl.
Why was carb rebuilt and ign module replaced ?
I too rebuilt a carb and replaced module on a 3.0 the other year.so i remember some things..but it was a Volvo Penta so has the luxury of having a Holley 2bbl.
#3
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The carb was rebuilt because the boat sat for 7 years before it was given to me. I changed all ignition components too because I could not confirm what worked and what didn't plus age. The distributor is the same but the pickup coil and rotor and cap is all new. The carb is good now as it starts and idles and performs otherwise perfectly. The jets are all clean and working perfectly and tested with a manual pump to ensure flow. The problem solely rides with the timing at this point. It just isn't doing what the book says it should do. Could it be yet another failed EST module? This is the third one. Original, then new one didn't even give me ignition and then this third new one is acting weird I think.
#4
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Okay thanks. I set things to total,,,don't give a damn to initial and i don;t have to set things at idle to make the EST go into base timing mode and etc.
I rev engine until the advance stops advancing and rev it a little higher to make sure,,,and then set total to that rpm,
I do have in my notes what AcDelco Module I installed in that EST distributor if you need that to compare ?
I rev engine until the advance stops advancing and rev it a little higher to make sure,,,and then set total to that rpm,
I do have in my notes what AcDelco Module I installed in that EST distributor if you need that to compare ?
#5
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Okay thanks. I set things to total,,,don't give a damn to initial and i don;t have to set things at idle to make the EST go into base timing mode and etc.
I rev engine until the advance stops advancing and rev it a little higher to make sure,,,and then set total to that rpm,
I do have in my notes what AcDelco Module I installed in that EST distributor is you need that to compare ?
I rev engine until the advance stops advancing and rev it a little higher to make sure,,,and then set total to that rpm,
I do have in my notes what AcDelco Module I installed in that EST distributor is you need that to compare ?
I can't set to total anyway because I don't have an advance timing light. Please let me know the module number? I got the last two from the local auto parts dealer who sells West Marine parts so it should be correct in both cases. I just think it's faulty is all I could see.
#6
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From: On A Dirt Floor
Found it. Got it thru Amazon as I get most of my ACDelco parts thru there. I buy tons of AcDelco parts. 
This one:
ACDelco D1965A GM Original Equipment Ignition Control Module
by ACDelco
Link: http://a.co/fGn9aJv
BTW: Do you know how to apply and what heat transfer paste to use with modules ?

This one:
ACDelco D1965A GM Original Equipment Ignition Control Module
by ACDelco
Link: http://a.co/fGn9aJv
BTW: Do you know how to apply and what heat transfer paste to use with modules ?
#8
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this is exactly what I got. The paste I used was in the box. I like to use the same paste that I use on CPU's. It is designed to be the best heat transfer.


