Well done.....not a Merc tech but maybe I can clear some stuff up from the automotive side....lets start with Chrysler "Fuel synch" in this vintage....on a scan tool, you could see a "plus/minus" fuel synch, which was actually the synchronization of the hall effect sensor in the distributor compared to the crank sensor. The engine computer would use this for: 1. troubleshooting 2. ignition timing on startup and 3. fuel injection synchronization - important to port fuel injected engines. The computer would use this info to figure out the firing order, and which piston was coming up on compression stroke so it knew when to fire the ignition and the fuel injector(s). In this case, ignition and fuel control controlled by computer, but has to identify the complete firing order (keep in mind, ratio is 2 crank revolutions to 1 cam revolution). The mfg's have all used their own magic to accomplish cam/crank/ignition timing and fuel syncrhonization - all same but different (enter Merc Marine!!!). It doesn't matter WHAT system you are working on, they are all the same but different in how the synch process is programmed and used by the module or computer or module operating the mess. What is really important is that the signals all jive, AND the rotor lines up at the right place in the distributor cap at the right time!. In the video, 22.5 degrees timing if the gear put on backwards - true, if you do the math....one tooth at the crank works out to 1/2 tooth at the cam, which is 22.5 degrees of ignition timing/rotor displacement/fuel synch being out of time on a V8 engine.....enough math!!!! This is useful to determine if a timing chain has jumped.....go figure.....diagnostic tip for the day??? The "dimple" on the gear has been around for a long long time. Quite often, if you put the gear on backwards, the roll pin hole won't line up (most Fords, and you can break the gear trying to drive it through) but the reasoning in the video is bang on - so DO NOT drill the shaft or the gear to make it fit. Been there, reman distributor with gear on backwards just about burnt an old ford to the ground with superheated catalytic converters from the poor confused computer. Check your work, match mark your stuff and get the right replacement parts! The dimple should be on the same side as the tip of the ignition rotor. Moving to GM - used to be super simple with old HEI systems - moving to newer vintage, the advent of more accurate timing and fuel injection complicated all of it - the distributors shown in the video are a GM base, and bastardized somewhat to make it Merc. The principles are the same as above. Crank engine, establish crank position and cam position, fire spark and fuel at the correct time. The trigger plate or sensor plate or reluctor (NOT the ignition rotor) is used to synchronize the crank and camshaft for the calculation process. Used to call it "doors and windows". These are used on a digital pickup (the black piece that the reluctor passes through) and create a digital signal. The older versions (Gm Ford Chrysler) used a magnetic pickup which created an analog signal. That technology should be long gone. Back to digital - the sensor in the distributor can be either magnetic or optical, and is usually called a Hall Effect type sensor. The signal is changed as a "door" from the reluctor starts to pass through the sensor and changes again when a "window" is passing by. Lots of information on the web! Chrysler used the same dame thing, just called it Fuel synch!! Ford - yup, same - called TFI IV. SO, the important things are number one cylinder position, the cam position (distributor reluctor), the ignition rotor to distributor cap or plug tower position, static timing, base timing and the manufacturer's module and programming. The "square base" GM distributors were manufactured to STOP people from messing with ignition timing and messing up fuel synch by cranking the distributor around. We used to grind notches in the hold down bracket, but it was to remedy cam synch issues with a stretched timing chain - the computer looks after the ignition timing!!!! Moving to Merc, predominantly Ford or GM based, but they change enough of the guts to make it proprietary so you are forced to try and buy their parts. A lot of the changes they make are for marine safety to reduce risk of explosion. Holley carbs come to mind!! So be wise if trying to retro fit and look closely at a replacement part from something other than Marine applications. Hope some of this helps, and have a good day!
From your experience, with a properly running Thunderbolt ignition, is the EST distributor any better for power or performance? Is the timing advance curve different? I know the thunderbolt module is longer available or too expensive, but is the EST better other than that?
The coil is fired by the module, not the trigger. How do you know the coil is working? If there is 12vdc on the module and coil and the trigger occurs, coil will fire regardless of timing.
The thunderbolt pickup is triggered optically. So the rotating leading edge of the metal spinning toothed disk blocks the infrared light at the sensor.
So I replaced my starter last year on my boat and I went to start it but it won’t fire. No spark coming out of the Ignition coil. There’s power to the coil/key on so I thought it’ll be a bad coil, went to replace it and still nothing! I’m not sure if the distributor sensor is the problem. Any suggestions?
@@moccasinmarine thanks! I’ll look into it. Before I replaced the starter I put a new fuel pump in it and she fired up. I thought the no/spark issue had to do something with the starter so I put the old one back in and it did absolutely nothing… so It’s just been sitting for a year 🤦🏽♂️
My other question is, does the neutral safety switch have to do with anything related to the coil causing no spark? Because I had to take apart the shifting mechanisms off the manifold riser so I had enough space to take the starter bolts off, “I didn’t mess with any of the shifting adjustments though” I’m not sure if that’ll be the issue either
Hola buenas yo tengo el mismo sistema e un mercruiser 7.4 v 8 i no hay manera de ponerlo a punto para que arranque ya que me da un error de que esta la chispa fuera de tiempo.como lo puedo llevar a el punto exacto gracias
@@moccasinmarine si lo tengo igual que vídeo he cambiado la bobina tapa de delco i rotor pero nada intento arrancar i a veces petardea i me suelta humo por el carburador
I’m having to translate to English but the problem you are describing is your distributor is 180 degrees out of time. You need to put the engine on Top Dead Center on cylinder 1 on the compression stroke, not the exhaust. The symptoms you are describing is when the distributor is 180° out of time.
You will probably have to buy an entire old boat to get that size engine. They weren’t used in cars or trucks so that leaves boats. They draw premium prices on Facebook marketplace but you could try Craigslist.
Well done.....not a Merc tech but maybe I can clear some stuff up from the automotive side....lets start with Chrysler "Fuel synch" in this vintage....on a scan tool, you could see a "plus/minus" fuel synch, which was actually the synchronization of the hall effect sensor in the distributor compared to the crank sensor. The engine computer would use this for: 1. troubleshooting 2. ignition timing on startup and 3. fuel injection synchronization - important to port fuel injected engines. The computer would use this info to figure out the firing order, and which piston was coming up on compression stroke so it knew when to fire the ignition and the fuel injector(s). In this case, ignition and fuel control controlled by computer, but has to identify the complete firing order (keep in mind, ratio is 2 crank revolutions to 1 cam revolution). The mfg's have all used their own magic to accomplish cam/crank/ignition timing and fuel syncrhonization - all same but different (enter Merc Marine!!!). It doesn't matter WHAT system you are working on, they are all the same but different in how the synch process is programmed and used by the module or computer or module operating the mess. What is really important is that the signals all jive, AND the rotor lines up at the right place in the distributor cap at the right time!. In the video, 22.5 degrees timing if the gear put on backwards - true, if you do the math....one tooth at the crank works out to 1/2 tooth at the cam, which is 22.5 degrees of ignition timing/rotor displacement/fuel synch being out of time on a V8 engine.....enough math!!!! This is useful to determine if a timing chain has jumped.....go figure.....diagnostic tip for the day???
The "dimple" on the gear has been around for a long long time. Quite often, if you put the gear on backwards, the roll pin hole won't line up (most Fords, and you can break the gear trying to drive it through) but the reasoning in the video is bang on - so DO NOT drill the shaft or the gear to make it fit. Been there, reman distributor with gear on backwards just about burnt an old ford to the ground with superheated catalytic converters from the poor confused computer. Check your work, match mark your stuff and get the right replacement parts! The dimple should be on the same side as the tip of the ignition rotor.
Moving to GM - used to be super simple with old HEI systems - moving to newer vintage, the advent of more accurate timing and fuel injection complicated all of it - the distributors shown in the video are a GM base, and bastardized somewhat to make it Merc. The principles are the same as above. Crank engine, establish crank position and cam position, fire spark and fuel at the correct time. The trigger plate or sensor plate or reluctor (NOT the ignition rotor) is used to synchronize the crank and camshaft for the calculation process. Used to call it "doors and windows". These are used on a digital pickup (the black piece that the reluctor passes through) and create a digital signal. The older versions (Gm Ford Chrysler) used a magnetic pickup which created an analog signal. That technology should be long gone. Back to digital - the sensor in the distributor can be either magnetic or optical, and is usually called a Hall Effect type sensor. The signal is changed as a "door" from the reluctor starts to pass through the sensor and changes again when a "window" is passing by. Lots of information on the web! Chrysler used the same dame thing, just called it Fuel synch!! Ford - yup, same - called TFI IV. SO, the important things are number one cylinder position, the cam position (distributor reluctor), the ignition rotor to distributor cap or plug tower position, static timing, base timing and the manufacturer's module and programming. The "square base" GM distributors were manufactured to STOP people from messing with ignition timing and messing up fuel synch by cranking the distributor around. We used to grind notches in the hold down bracket, but it was to remedy cam synch issues with a stretched timing chain - the computer looks after the ignition timing!!!!
Moving to Merc, predominantly Ford or GM based, but they change enough of the guts to make it proprietary so you are forced to try and buy their parts. A lot of the changes they make are for marine safety to reduce risk of explosion. Holley carbs come to mind!! So be wise if trying to retro fit and look closely at a replacement part from something other than Marine applications.
Hope some of this helps, and have a good day!
Thanks for the collaborating post. You might like this video also.
th-cam.com/video/MYiAo-gAT1Q/w-d-xo.html
From your experience, with a properly running Thunderbolt ignition, is the EST distributor any better for power or performance? Is the timing advance curve different? I know the thunderbolt module is longer available or too expensive, but is the EST better other than that?
This is a good question and I’ll research and do a video on the timing curve comparisons. But right now I don’t have an answer for this question.
Can the timing make it to not trigger the coil at all?, my coil is working but doesnt get the trigger signal.
The coil is fired by the module, not the trigger. How do you know the coil is working? If there is 12vdc on the module and coil and the trigger occurs, coil will fire regardless of timing.
My distributor only has 2 wires coming from it. Is that normal? 1998 baylinercapri 1850ls 4.3l mercruiser with thunderbolt
Yes it’s normal on some boats
What do you mean by "The trigger is actually the leading edge of the metal tab"?
The thunderbolt pickup is triggered optically. So the rotating leading edge of the metal spinning toothed disk blocks the infrared light at the sensor.
@@moccasinmarine Ok, thank you:)
So I replaced my starter last year on my boat and I went to start it but it won’t fire. No spark coming out of the Ignition coil. There’s power to the coil/key on so I thought it’ll be a bad coil, went to replace it and still nothing! I’m not sure if the distributor sensor is the problem. Any suggestions?
My bet is on the Thunderbolt ignition module. It tends to go bad for no reason.
@@moccasinmarine thanks! I’ll look into it. Before I replaced the starter I put a new fuel pump in it and she fired up. I thought the no/spark issue had to do something with the starter so I put the old one back in and it did absolutely nothing… so It’s just been sitting for a year 🤦🏽♂️
My other question is, does the neutral safety switch have to do with anything related to the coil causing no spark? Because I had to take apart the shifting mechanisms off the manifold riser so I had enough space to take the starter bolts off, “I didn’t mess with any of the shifting adjustments though” I’m not sure if that’ll be the issue either
@@moccasinmarine Any ideas where the module is located on the 97 5.7?
Neutral safety switches only prevent it from starting. Has nothing to do with a running engine.
Hola buenas yo tengo el mismo sistema e un mercruiser 7.4 v 8 i no hay manera de ponerlo a punto para que arranque ya que me da un error de que esta la chispa fuera de tiempo.como lo puedo llevar a el punto exacto gracias
Testing
th-cam.com/video/5v2LQVcUD_c/w-d-xo.html
Watch this video and make sure engine is on TDC on #1 on the compression stroke.
@@moccasinmarine si lo tengo igual que vídeo he cambiado la bobina tapa de delco i rotor pero nada intento arrancar i a veces petardea i me suelta humo por el carburador
I’m having to translate to English but the problem you are describing is your distributor is 180 degrees out of time. You need to put the engine on Top Dead Center on cylinder 1 on the compression stroke, not the exhaust. The symptoms you are describing is when the distributor is 180° out of time.
@@moccasinmarine ya lo tengo pero ahora creo que tengo las bujías ahogadas de gasolina mañana cambio las bujías i te cuento
Any idea where I can find a 3.0 block?
You will probably have to buy an entire old boat to get that size engine. They weren’t used in cars or trucks so that leaves boats. They draw premium prices on Facebook marketplace but you could try Craigslist.
My thunderbolt plug is different