Don't rule out the possibility of pre-ignition due to a hot spot in one of the cylinders. The hot spot could be either carbon buildup or possibly a plug with too long a reach or electrode bent wrong.
Hey I’m kinda new to the channel and the reed videos are pretty awesome. If I can give you some input, while watching the video I find myself trying to figure out what your working on or doing. What I mean is, I’d love just a little more detail at the start to understand what your working on. Year, motor, and whatever. You do give info , just tend to leave out a few details that would help a average joe like myself better understand. Thanks again and keep up the channel it’s awesome
Sean, as you begin to learn Mercury outboards, you will discover that all through the 1980”s and most of the 90’s there is huge overlap and similarities so whatever outboard he’s working on, will almost certainly be useful for you to learn from unless you have Optimax or newer.
My 135 hp 1998 Mercury gets hot too, not at idling or below 1500 rpm but as soon as I accelerate above 2,000 or 3,000 rpm. Temperature alarm starts sounding and temperature gauge reads 3/4 in less than a minute if I accelerate into planning speeds at 5,000 rpm. I see that when you were trying to start the engine the flywheel stopped all of a sudden, which is very difficult considering the inertial forces of all 6 cylinders spinning including your lightweight flywheel. A very strong force is necessary to quit the circular movement so suddenly. An out of tine spark at 90° is a huge force able to stop the circular movement. Seems like a clear symptom of an out of time firing. I have a standard heavy flywheel and my engine also stops suddenly when gasoline first arrive while attempting starting the engine, but at third try engine starts normally same as yours. I have spares four ignition modules and two high speed advance spark timing a d idling stabilizer low speed spark advance modules from two other 135hp 1987 engines. I read somewhere that we need to read the resistance to ground from all six ignition coils after removing the ground connection from each coil to ground, They should read very high mega ohms resistance as I understood. Can you g in be us your megohms? It seems to me that we need the electronic diagrams from all three electronic devices, or replace all of them with new o.m. replacements, including the inner and outer switch boxes that are the devices that give the impulse of a discharged capacitor through some Tyrystior (just guessing). I refuse to send my engine to the garbage.
Very interesting what you said during one minute between 14:45 and 15:45. You get a spark at the right time but also another spark 90 degrees before the right time, since the flywheel is rotating clockwise. The extra spark is probably what causes the out ofvtime pop that you hear, what causes the overheating cylinder when gasoline tlwas forced to be burnt inside the cylinder instead of at the exhaust manifold, and what caused the engine to stop rotating suddenly sometimes when you attempted to start the engine also. Everything makes sense, if we understand that gasoline must be burnt at the exhaust manifold but never insude a cylinder! The explanation of how an engine works is false. Piston is not being pushed down from the gases after each ignition. Those gases are being formed after the gasoline is burnt at the exhaust manifold. What causes the piston to be pushed at the right time is something else, an instant pop that does not increase the temperature, not the gases from burnt gasoline that do increase the temperatureof the exhaust manifold outside the cylinder.
I love your videos. I'm giving an older Rander a second chance that has a 200hp V6. I know nothing about the unit other than it has around 132 psi in every hole and fires right up (as long as the kill switch is hooked up). It does "spit" water out of the tell when on the muffs. Have you ever seen that? New impeller.
could you explain the testing process you did to find the bad coil? im having a similar issue. while timing the engine on #3. i see #1 #3 and #5 flashing when only #3 should be firing. i havent installed my new CDI SBs yet. i dont want to destroy them if my coils have a problem like yours
Check your flywheel trigger magnets too, hairline crack or chip. Don’t rule the flywheel out. Been bit by this before. Another check that may or may not help it check for double spark on the other cylinder in the batch… the trigger has 3 coils, one per two cyl. If the flywheel is an issue it should affect both cylinders…. “In theory”
Thanks. I did a pole check on the mains magnets and they seemed fine. That hub group for the trigger is tricky to check by hand with another magnet. I can't be sure if it's good or not. If you have any ideas to pass on I'd appreciate it. No chips or visible cracks though but the hub mags are double stacked with a jacket so I'd never know if the bottom set were cracked.
At 13:13 we see that engine suddenly stops moving when you were trying to start the engine. This fact alone should be enough reason to suspect of an out of time spark which causes a strong instant brake.
Have you checked exhaust manifold water conduction holes? They should be cleaned every once in a while because water may carry deposits or salt that will stick there.
A TYPICAL WATER BLOCKAGE AREA IS AT THE TOP OF THE BLOCK JUST UNDERNEATH THE LARGE PLUG WHICH CLOSES OFF THE LONG CORED PASSAGEWAY COMING UP FROM THE BOTTOM OF THE BLOCK. SO PULL THAT PLUG AND LOOK FOR DEBRII THERE WHICH IS CLOSING OFF THE PASSAGEWAY INTO THE EXHAUST COVER. GOOD LUCK!
brother I am trying to find you on scream and fly, says your name is the same, can't find you, need a little more info, what was causing the double fire? I think I am having the same issue on my 92 2.5L
I never did make another video after I isolated the issue. I put up a thread on Scream&Fly with all updates though. The problem was the coil on cylinder 4. It was taking the switchboxes out immediately. Took a CDI tech helping over the phone to figure it out. The coil measured normal connected and even fired on time but....also fired again out of time. Supposedly the bad coil was back feeding voltage and taking out a blocking diode in the switchbox is what the second fire was caused from. Makes sense now. Seemed like I went through switchboxes more often than friends over the years. This set of coils has been with all of them that failed. Problem finally came to a head though. I put a full set of new coils on along with yet another set of SBs. Problem solved!
@@SmalltownBassinSo... Does or does not your engine over heats anymore after replacing coils and switch boxes? Were they new switch boxes or second hand? At first I thought that a bad coil cannot be the problem because a coil is simply a number of turns on the primary and a bunch of turns of wire on the secondary, winded around a number of iron sheets. One side of the coil goes to ground and the other side goes to the switch box on the primary and the high voltage on the secondary goes to the spark plug. This transformer either works or not works, but I wouldn't imagine that e bad coil could blow switch boxes. It must be that the secondary high voltage winding was sending high voltage to the switch box blowing the diode of the new switch box.
@@SmalltownBassin will do. Love your videos by the way. Extremely informative watching all the things you read about, getting done in real life. I too learned about double firing from scream and fly. Dangerous thing that could be. Could in a worse case leave you stranded on the lake. Totally looking forward to seeing your next video in the overheating saga now you know you have a double firing switch box.
One more thing you might want to look into… one of the big dogs on S&F said that the genuine Sierra Marine switch boxes are made in Germany and are very good (and expensive too of course). The ones you have look like the yellow potting material is too light, like the color of pee. Same shade as the $50 Chinese boxes on Amazon. When I google pics of sierra boxes, their potting material is much darker shade. Just food for thought. Maybe dig a little deeper and make sure your double firing boxes are real sierra and not counterfeit.
Thanks man! And yeah they are genuine. Had a set come bad out of the box and called them, they sent these. Genuine PRUFEX made in Germany is cast into the black plastic. Since that last video and about 6 more sets of SBs I've swapped coils, trigger, stator, ignition switch, flywheels and 2 more sets of SBs and right this very second, it's firing on all 6. Just finished the SB install about 30 minutes ago lol and right this second, it's not double firing.
@@SmalltownBassin wow! What an adventure! Goes to show even the good stuff can be bad sometimes. Looking forward to the video with it NOT overheating ;)
I heard that extra pop, owning these since ‘62 has been a journey!! Great vid
Don't rule out the possibility of pre-ignition due to a hot spot in one of the cylinders. The hot spot could be either carbon buildup or possibly a plug with too long a reach or electrode bent wrong.
Everything I’ve read said there are no bench test for switch boxes. Great video and I saw the bite from the spark plug wire.
Hey I’m kinda new to the channel and the reed videos are pretty awesome. If I can give you some input, while watching the video I find myself trying to figure out what your working on or doing. What I mean is, I’d love just a little more detail at the start to understand what your working on. Year, motor, and whatever. You do give info , just tend to leave out a few details that would help a average joe like myself better understand. Thanks again and keep up the channel it’s awesome
Thanks for watching! And well put man. I'll keep that in mind. I appreciate that.
Sean, as you begin to learn Mercury outboards, you will discover that all through the 1980”s and most of the 90’s there is huge overlap and similarities so whatever outboard he’s working on, will almost certainly be useful for you to learn from unless you have Optimax or newer.
My 135 hp 1998 Mercury gets hot too, not at idling or below 1500 rpm but as soon as I accelerate above 2,000 or 3,000 rpm. Temperature alarm starts sounding and temperature gauge reads 3/4 in less than a minute if I accelerate into planning speeds at 5,000 rpm.
I see that when you were trying to start the engine the flywheel stopped all of a sudden, which is very difficult considering the inertial forces of all 6 cylinders spinning including your lightweight flywheel. A very strong force is necessary to quit the circular movement so suddenly. An out of tine spark at 90° is a huge force able to stop the circular movement. Seems like a clear symptom of an out of time firing.
I have a standard heavy flywheel and my engine also stops suddenly when gasoline first arrive while attempting starting the engine, but at third try engine starts normally same as yours.
I have spares four ignition modules and two high speed advance spark timing a d idling stabilizer low speed spark advance modules from two other 135hp 1987 engines. I read somewhere that we need to read the resistance to ground from all six ignition coils after removing the ground connection from each coil to ground, They should read very high mega ohms resistance as I understood. Can you g in be us your megohms?
It seems to me that we need the electronic diagrams from all three electronic devices, or replace all of them with new o.m. replacements, including the inner and outer switch boxes that are the devices that give the impulse of a discharged capacitor through some Tyrystior (just guessing).
I refuse to send my engine to the garbage.
Very interesting what you said during one minute between 14:45 and 15:45.
You get a spark at the right time but also another spark 90 degrees before the right time, since the flywheel is rotating clockwise.
The extra spark is probably what causes the out ofvtime pop that you hear, what causes the overheating cylinder when gasoline tlwas forced to be burnt inside the cylinder instead of at the exhaust manifold, and what caused the engine to stop rotating suddenly sometimes when you attempted to start the engine also.
Everything makes sense, if we understand that gasoline must be burnt at the exhaust manifold but never insude a cylinder!
The explanation of how an engine works is false.
Piston is not being pushed down from the gases after each ignition.
Those gases are being formed after the gasoline is burnt at the exhaust manifold.
What causes the piston to be pushed at the right time is something else, an instant pop that does not increase the temperature, not the gases from burnt gasoline that do increase the temperatureof the exhaust manifold outside the cylinder.
Adam in this video I can hear the difference in the sound of motor because of the flywheel,
I cleaned up my steel red wheel to try when the new electronics come in. The switchboxes were already toast when we tried yours.
I love your videos. I'm giving an older Rander a second chance that has a 200hp V6. I know nothing about the unit other than it has around 132 psi in every hole and fires right up (as long as the kill switch is hooked up). It does "spit" water out of the tell when on the muffs. Have you ever seen that? New impeller.
Thanks for watching! Is it overheating?
could you explain the testing process you did to find the bad coil? im having a similar issue. while timing the engine on #3. i see #1 #3 and #5 flashing when only #3 should be firing. i havent installed my new CDI SBs yet. i dont want to destroy them if my coils have a problem like yours
Check your flywheel trigger magnets too, hairline crack or chip. Don’t rule the flywheel out. Been bit by this before. Another check that may or may not help it check for double spark on the other cylinder in the batch… the trigger has 3 coils, one per two cyl. If the flywheel is an issue it should affect both cylinders…. “In theory”
Thanks. I did a pole check on the mains magnets and they seemed fine. That hub group for the trigger is tricky to check by hand with another magnet. I can't be sure if it's good or not. If you have any ideas to pass on I'd appreciate it. No chips or visible cracks though but the hub mags are double stacked with a jacket so I'd never know if the bottom set were cracked.
@@SmalltownBassin pm’d on Facebook!!
At 13:13 we see that engine suddenly stops moving when you were trying to start the engine.
This fact alone should be enough reason to suspect of an out of time spark which causes a strong instant brake.
The electronics may test good when the motor is cold but when the motor is up to operating temperature could test bad.
Have you checked exhaust manifold water conduction holes? They should be cleaned every once in a while because water may carry deposits or salt that will stick there.
A TYPICAL WATER BLOCKAGE AREA IS AT THE TOP OF THE BLOCK JUST UNDERNEATH THE LARGE PLUG WHICH CLOSES OFF THE LONG CORED PASSAGEWAY COMING UP FROM THE BOTTOM OF THE BLOCK. SO PULL THAT PLUG AND LOOK FOR DEBRII THERE WHICH IS CLOSING OFF THE PASSAGEWAY INTO THE EXHAUST COVER. GOOD LUCK!
Que hermoso trabajo !! Cuantas RPM esta dando ese motor ?
Have you rotated Stator I think it may needs to be rotated, I believe the white coils need to be to the back
brother I am trying to find you on scream and fly, says your name is the same, can't find you, need a little more info, what was causing the double fire? I think I am having the same issue on my 92 2.5L
I just replied with my phone number. Give me call.
That is crazy, never thought it could be that 🤔
I need that on my tracker.😮
Wish you could of change camera angles so we can see what you are doing.
Detonation?
Change the fly wheel to stock check that
What about lean mixtures, too much air or low amounts of gasoline makes engines get too hot.
YOu could switch the switch boxes from one bank to the other and see if the 'double fire' or lean condition moves cylinders.
I never did make another video after I isolated the issue. I put up a thread on Scream&Fly with all updates though. The problem was the coil on cylinder 4. It was taking the switchboxes out immediately. Took a CDI tech helping over the phone to figure it out. The coil measured normal connected and even fired on time but....also fired again out of time. Supposedly the bad coil was back feeding voltage and taking out a blocking diode in the switchbox is what the second fire was caused from. Makes sense now. Seemed like I went through switchboxes more often than friends over the years. This set of coils has been with all of them that failed. Problem finally came to a head though. I put a full set of new coils on along with yet another set of SBs. Problem solved!
@@SmalltownBassin how did you check the coil?
@@SmalltownBassinSo... Does or does not your engine over heats anymore after replacing coils and switch boxes?
Were they new switch boxes or second hand?
At first I thought that a bad coil cannot be the problem because a coil is simply a number of turns on the primary and a bunch of turns of wire on the secondary, winded around a number of iron sheets. One side of the coil goes to ground and the other side goes to the switch box on the primary and the high voltage on the secondary goes to the spark plug. This transformer either works or not works, but I wouldn't imagine that e bad coil could blow switch boxes.
It must be that the secondary high voltage winding was sending high voltage to the switch box blowing the diode of the new switch box.
Is the slinger seal on to of the pump, it's hard to tell
Yes. Tried everything though. With and without it but found the bad coil causing the problems.
What is your "name" on scream and fly? I'm there too :)
Same "smalltownbassin". Hit me up man!
@@SmalltownBassin will do. Love your videos by the way. Extremely informative watching all the things you read about, getting done in real life. I too learned about double firing from scream and fly. Dangerous thing that could be. Could in a worse case leave you stranded on the lake. Totally looking forward to seeing your next video in the overheating saga now you know you have a double firing switch box.
One more thing you might want to look into… one of the big dogs on S&F said that the genuine Sierra Marine switch boxes are made in Germany and are very good (and expensive too of course). The ones you have look like the yellow potting material is too light, like the color of pee. Same shade as the $50 Chinese boxes on Amazon. When I google pics of sierra boxes, their potting material is much darker shade. Just food for thought. Maybe dig a little deeper and make sure your double firing boxes are real sierra and not counterfeit.
Thanks man! And yeah they are genuine. Had a set come bad out of the box and called them, they sent these. Genuine PRUFEX made in Germany is cast into the black plastic. Since that last video and about 6 more sets of SBs I've swapped coils, trigger, stator, ignition switch, flywheels and 2 more sets of SBs and right this very second, it's firing on all 6. Just finished the SB install about 30 minutes ago lol and right this second, it's not double firing.
@@SmalltownBassin wow! What an adventure! Goes to show even the good stuff can be bad sometimes. Looking forward to the video with it NOT overheating ;)
🤟🤟🤟🤟
Check your poppet valve
👍🏽
That is more than likely what cooked and broke your reed a while back