Caps can develop small interior cracks that change with temperature. They attract microscopic carbon deposits that cause all kinds od nearly impossible to detect misfire conditions. If you suspect the cap(s) ditch them. If they are real old ditch them for sure IMO.
I have heard a faulty tach can cause no spark. @Alswagg might be able to validate if that is true or not.
i'm certainly not Al, but yes... it depends on the tach... some swap polarity even though the harness attaches the same, and a grounded dizzy doesnt spark where it's supposed to spark..
I would think the tach would be an all or nothing kind of fault? I am no technician, but I think the problem is due to a failing (not failed) part, as the engine has ran at idle. The coil wire makes sense to me as that could cause all my engines symptoms, but I would think it would stay running longer? Not sure on that one. Perhaps the coil itself, but again I would think it would cause a no start condition all the time, I am not sure if the crank position sensor would cause my issues, I have never had that problem, but if Al read the post and suggested I check it out, I am sure gonna do that. Like I said above, I pulled a plug, semi-grounded it to the block and cranked the engine over (about 10-15 seconds of cranking), there was no "regular" spark, but I did get one bright spark. I know the wires haven't been changed in the last 4 or 5 years, original coil and original cap and rotor (2005 boat), I am considering buying all of it since they are old enough to be replaced anyway. I have thrown a ton of money at this engine and I dont' have a solution yet, so that aspect is stopping me from blindly throwing more money at it.
Update: tried to start motor without changing anything first, wouldn't start at all. Swapped the coil wire from good engine to bad, started right up. Will get a new set of wires on it tommorrow and put boat in water tomorrow to test further. Thanks for all your help!!! Truly grateful.
i had two families on a boat once... took them to dinner on the waterfront... went without a hiccup the entire time... had to outrun a storm on the way back to home... it was right on our tale... let everyone get in their vehicles at the launch, and told them I'd scoop the boat, and to have a drink ready for me when I got there- I should have been less than five minutes behind them... tied the boat up and fetched the truck, backed trailer down the ramp.. walked back to pier where boat was tied, and noticed approaching it that it wasn't running.. would NOT fire back up...
i had to toss a line from post to post, and pull the boat the fifty or so yards to the ramp, and hand crank it up- while the wind was howling and lightning flashing almost daylight...
i had spark at the coil, which is where i started.. moved along from there.. i couldn't figure it out initially... went through motions elsewhere just to come back to spark- but this time pulled the center off the dizzy tower... I didn't even have to check to see if it sparked... it was obvious... the filament was totally rotten... it looked fine from the outside, but the ring stayed on the tower and the wire pulled right off... what was filament was a rotten mushy mess... problem solved...
Sounds miserable! Great story though! I do not have high hopes because I thought the last three fixes were going to be "the one". I have positive signs, it started! But will wait for the water test before I get happy this time!
Thanks for all the help!
Al,
I will be very careful replacing those! Thanks for the tip!
I posted a pic on here of breaking that tab on the distributor. $$$. Be very careful. I use a hand driver with the torx bit. Too easy to over torque and crack with even a 1/4" ratchet.
Remove the IAC filter in the throttle body. I had a problem last summer with shift stall. This filter can get very dirty via carbon/oil stuff. It will cause increased noise removed, but if it fixes it, replace or clean with brake cleaner.
It sounds like you changed the boat mounted water separator, but did you change engine mounted filter to the Gen 2 fuel system? If it's a Gen 3, it will be a cartridge filter (black handle with 3 fasteners).
Did not get the chance to put boat in the water last night, couldn't find anywhere that had the correct ignition wires, ordered them instead. Believe it or not, iboats had the best prices! We are going out of town for the long weekend anyway, the new wires will be on my porch when I get back.
Question: Just for giggles I put the old coil wire back in it's proper place, the engine started right up!!! Does manipulating the wire, removing it and putting it back on, somehow make the connection TEMPORARILY usable again? The only thing I could guess was moving the wire around somehow fixed it, but only a matter of time before it doesn't work again. Is this hypothesis valid? Do coil wires play games with your head like that?
^ bingo... which is why I said the symptoms were consistent with a bad wire...
and the reason I shared that tale above.... the boat didn't miss a beat until it was idling while I retrieved the trailer... it died and that was it.... now, chances are I could have tried later and connectivity, however feeble, could have been restored and using maybe a strand or two of the filament, but a jostle this way or that? POOF GONE.... only to work again at another random time...
think of it as a loose wire connection in a electronic device... which is precisely what it is... intermittent connectivity... it isn't shorting, it just isn't well seated.
Well, the saga continues. Changed coil wire out with brand new one and it still won't start. This is getting ridiculous, so I ordered a new coil and new crankshaft position sensor. If one of those don't fix it, I will give up and take it to a professional, where I won't see it till August.
Keep your eye on the horizon. You're going to find out what the issue is and then smack yourself on the forehead, when it becomes clear. All this will be history, and you will be happy having a working boat again.
Ok, so the saga continues...it's June for crying out loud. Still haven't been on the boat, wife is threatening all kinds of things. Got the new coil yesterday, went over to install today and found the bolts I picked up don't fit, but it was driving me nuts so I plugged in the coil (three connections) and fired the engine. It started up first thing, but it surged on idle between 800-1400RPMs. It did this for about two or three minutes then died and would not restart. Anyone know if a faulty Crankshaft Sensor Position Sensor can cause my symptoms? I have a brand new one to put on, but it's a real b$%@ to get to. I am ordering a code puller from this website: http://www.mefiburn.com/sc/cart.asp || Does anyone have experience with these? I can't afford the good one...$800!
Can you hang a video of this off YouTube and link it for us?
Does it cough at all when you turn it after it dies?
A ckps usually gives indication of issues by skipping/misfiring at higher tpms, then at a wider range, then kapooy, it's over and isn't heard from again.
When thos happens again, pull a boot off a plug... put a new spark plug in the boot and place it on your intake manifold where the threads touch the block.. turn the key in on position.. grab a pair of insulated handle pliers, and bridge the posts on your slave solenoid. Watch to see if the plug sparks.
We just replaced the ckps the other day. Still wouldn't start up. For any VP guru's out there, both engines have always beeped twice nice and loud when the key is first turned on, after some research I found out this is a "self-check" of sorts, internal diagnostic thing. My good engine (starboard side) still does that, it beeps twice when the key is first turned on. The port engine only beeps once and it is a weak sounding beep. The list of replaced parts:
New throttle body, IAC and TPS New fuel pump (checks out okay) fuel pressure regulator (removed screen, replaced with clip as per the VP bulletin) New coil New spark plugs New spark plug wires
New cooling system. All new heat exchanger and hoses, but come to think of it, it hasn't ran right since installed.
New aftermarket starter....could any of the connections on the starter be causing this problem? Starboard engine has new starter as well, it doesn't have any issues.
Thoroughly cleaned the flame arrestor as it was gunked up
Engine occasionally (random times) will run at "surge" idle (800-1400rpm) for a minute or two, then it dies and won't restart.
The last time I pulled a plug and checked for spark, I had one nice bright spark in about 50 or 60 revolutions. But this could have been due to a poor ground on the side of the engine. I intend to pick up one of those "in-line" spark testers, it leaves the plug installed and flashes when the signal is going through the line. Plugs should all be good, they are new AC Delco. I have diagnostic tool on the way, should allow me to see the codes the ECM is spitting out.
i wager you've got a cracked cap... hairline... brand new or not... or, you're like my recent discovery of grounding somewhere with an internally damaged plug wire...
the filament in those things are graphite spray covered... they are a lot more fragile than you'd think... a stretch, a sharp bend... a hot spot... they're toast...
if'n I was you, I'd swap caps just for good measure... they aren't that expensive... then, I'd pull a wire off the tower one by one until that engine fires and runs (albeit a cylinder shy)... and that will tell you which wire is spraying your spark under the cap...
you should be able to not only see a strong spark, you should be able to HEAR it.. POP... not (crackle)....
I never really considered the cap. I guess I could switch out the one on the good motor over to the bad motor and see if that cures it. As for the rest, I am not sure I understand? You are saying the connections inside the cap are bad? This is an MPI model. So in short, swap caps, see if she runs and if so, start pulling plug wires one by one to find out.....what? If the cap itself is the issue, wouldn't swapping it for a good fix it? Or is there another issue inside the distributor that I am missing? I really wish I had a good old distributor with points and a condenser inside and a carb! Would make things simpler for sure.
caps develop cracks due to heat and such... they allow moisture in, or allow grounding at improper places. they can do this for seemingly no good reason.
It wouldn't run nor likely even cough if your timing chain is broken, as the valve train wouldn't actuate... but if you've jumped valve timing by skipping a tooth or two, it could also be an issue.... but I doubt it.. even on a sloppy chain, there is a tensioner in there and the taught side of the chain will remain taught no matter the slop on the other with that tensioner involved.
take out plug #1... facing engine, right side front plug... put your finger over the hole loosely... bump engine with starter until you feel air no longer compressing against your finger.. turn it ever so slightly until you feel it pull your finger toward it, then use a pry bar between bolts on your crank pulley to reverse the rotation ever so slightly back to where it was before it started sucking... this is top dead center (TDC), or close enough to it for government work... if your harmonic balancer is marked, it should also indicate TDC...
pull your dizzy cap, and observe... the rotor button 'should' be pointing pretty much directly at cylinder one. carefully install the cap, making sure it's seated and sealed- no gorilla strength required- actually strictly forbidden.
the tower on the cap that is directly over the rotor button is now your #1 plug wire.... take your longest (new) plug wire and run it to that cylinder, while making sure it's routing is safe (under linkage, under manifolds, not stretched, no sharp bends)...
the firing order is 1 (the one you just did) and going clockwise around the dizzy, next is 8, then 4, then 3, then 6, then 5. then 7, then two... two has to be a long wire, and be mindful of the wires that cross over to the opposite side of the dizzy as they'll have to be longer too... it's best to lay the wires out first so you can judged the length you'll need... it's also best to have two sets of new wires, and use the longer ones from both sets...
do these one by one... it's a good time to swap plugs, too, if it's been a while... opinions differ, but good ol' copper is what I rec...
I wager your issue will be resolved at the end of this activity... I bet you're spraying spark... I wager that as soon as your spark finds ground outside the wire or under that cap (usually higher RPM or under load) it doesn't let it go, and your ignition timing is out the window- you may as well be 90 or 180 out at that point...
Thanks! I will be checking that Friday night. I have been meaning to check for arcing at night. The plugs and wires are all brand new, AC delco on the plugs and OEM from VP for the wires.
Comments
i had to toss a line from post to post, and pull the boat the fifty or so yards to the ramp, and hand crank it up- while the wind was howling and lightning flashing almost daylight...
i had spark at the coil, which is where i started.. moved along from there.. i couldn't figure it out initially... went through motions elsewhere just to come back to spark- but this time pulled the center off the dizzy tower... I didn't even have to check to see if it sparked... it was obvious... the filament was totally rotten... it looked fine from the outside, but the ring stayed on the tower and the wire pulled right off... what was filament was a rotten mushy mess... problem solved...
Sounds miserable! Great story though! I do not have high hopes because I thought the last three fixes were going to be "the one". I have positive signs, it started! But will wait for the water test before I get happy this time!
Thanks for all the help!
Al,
I will be very careful replacing those! Thanks for the tip!
Patrick
PC BYC, Holland, MI
http://rinkerboats.vanillaforums.com/discussion/4468/350-mag-mpi-distributor#latest
PC BYC, Holland, MI
Wow! This forum is invaluable, thanks guys!
Remove the IAC filter in the throttle body. I had a problem last summer with shift stall. This filter can get very dirty via carbon/oil stuff. It will cause increased noise removed, but if it fixes it, replace or clean with brake cleaner.
It sounds like you changed the boat mounted water separator, but did you change engine mounted filter to the Gen 2 fuel system? If it's a Gen 3, it will be a cartridge filter (black handle with 3 fasteners).
Question: Just for giggles I put the old coil wire back in it's proper place, the engine started right up!!! Does manipulating the wire, removing it and putting it back on, somehow make the connection TEMPORARILY usable again? The only thing I could guess was moving the wire around somehow fixed it, but only a matter of time before it doesn't work again. Is this hypothesis valid? Do coil wires play games with your head like that?
and the reason I shared that tale above.... the boat didn't miss a beat until it was idling while I retrieved the trailer... it died and that was it.... now, chances are I could have tried later and connectivity, however feeble, could have been restored and using maybe a strand or two of the filament, but a jostle this way or that? POOF GONE.... only to work again at another random time...
think of it as a loose wire connection in a electronic device... which is precisely what it is... intermittent connectivity... it isn't shorting, it just isn't well seated.
PC BYC, Holland, MI
Boat Name: King Kong
"Boat + Water = Fun"
Does it cough at all when you turn it after it dies?
A ckps usually gives indication of issues by skipping/misfiring at higher tpms, then at a wider range, then kapooy, it's over and isn't heard from again.
When thos happens again, pull a boot off a plug... put a new spark plug in the boot and place it on your intake manifold where the threads touch the block.. turn the key in on position.. grab a pair of insulated handle pliers, and bridge the posts on your slave solenoid. Watch to see if the plug sparks.
New throttle body, IAC and TPS
New fuel pump (checks out okay)
fuel pressure regulator (removed screen, replaced with clip as per the VP bulletin)
New coil
New spark plugs
New spark plug wires
New cooling system. All new heat exchanger and hoses, but come to think of it, it hasn't ran right since installed.
New aftermarket starter....could any of the connections on the starter be causing this problem? Starboard engine has new starter as well, it doesn't have any issues.
Thoroughly cleaned the flame arrestor as it was gunked up
Engine occasionally (random times) will run at "surge" idle (800-1400rpm) for a minute or two, then it dies and won't restart.
The last time I pulled a plug and checked for spark, I had one nice bright spark in about 50 or 60 revolutions. But this could have been due to a poor ground on the side of the engine. I intend to pick up one of those "in-line" spark testers, it leaves the plug installed and flashes when the signal is going through the line. Plugs should all be good, they are new AC Delco. I have diagnostic tool on the way, should allow me to see the codes the ECM is spitting out.
i wager you've got a cracked cap... hairline... brand new or not... or, you're like my recent discovery of grounding somewhere with an internally damaged plug wire...
the filament in those things are graphite spray covered... they are a lot more fragile than you'd think... a stretch, a sharp bend... a hot spot... they're toast...
if'n I was you, I'd swap caps just for good measure... they aren't that expensive... then, I'd pull a wire off the tower one by one until that engine fires and runs (albeit a cylinder shy)... and that will tell you which wire is spraying your spark under the cap...
you should be able to not only see a strong spark, you should be able to HEAR it.. POP... not (crackle)....
It wouldn't run nor likely even cough if your timing chain is broken, as the valve train wouldn't actuate... but if you've jumped valve timing by skipping a tooth or two, it could also be an issue.... but I doubt it.. even on a sloppy chain, there is a tensioner in there and the taught side of the chain will remain taught no matter the slop on the other with that tensioner involved.
take out plug #1... facing engine, right side front plug... put your finger over the hole loosely... bump engine with starter until you feel air no longer compressing against your finger.. turn it ever so slightly until you feel it pull your finger toward it, then use a pry bar between bolts on your crank pulley to reverse the rotation ever so slightly back to where it was before it started sucking... this is top dead center (TDC), or close enough to it for government work... if your harmonic balancer is marked, it should also indicate TDC...
pull your dizzy cap, and observe... the rotor button 'should' be pointing pretty much directly at cylinder one. carefully install the cap, making sure it's seated and sealed- no gorilla strength required- actually strictly forbidden.
the tower on the cap that is directly over the rotor button is now your #1 plug wire.... take your longest (new) plug wire and run it to that cylinder, while making sure it's routing is safe (under linkage, under manifolds, not stretched, no sharp bends)...
the firing order is 1 (the one you just did) and going clockwise around the dizzy, next is 8, then 4, then 3, then 6, then 5. then 7, then two... two has to be a long wire, and be mindful of the wires that cross over to the opposite side of the dizzy as they'll have to be longer too... it's best to lay the wires out first so you can judged the length you'll need... it's also best to have two sets of new wires, and use the longer ones from both sets...
do these one by one... it's a good time to swap plugs, too, if it's been a while... opinions differ, but good ol' copper is what I rec...
I wager your issue will be resolved at the end of this activity... I bet you're spraying spark... I wager that as soon as your spark finds ground outside the wire or under that cap (usually higher RPM or under load) it doesn't let it go, and your ignition timing is out the window- you may as well be 90 or 180 out at that point...