4.3 omc cobra no start

[Xlanci]

Hey guys new to this forum but was wondering if anyone could help me out with this tricky issue so basically I bought this boat at the dudes house it started but when I brought it home no start automatically went to the ignition system after trying to start it for so long and not getting any backfires or major shaking but it has spark so I checked compression and it had that as well then checked fuel it had plenty of that even swapped tanks to make sure nothing was in it then I also replaced the ignition coil and condenser as well as the spark plugs I’ve tried retapping everything still no luck I’m running out of ideas to try hopefully some can help me with this thanks for y’all’s tkne

 

[alldodge]

Where are you checking for spark?
If checking at the coil wire, see if the rotor is turning

 

[Bondo]

Ayuh,..... Welcome Aboard,..... Are the sparkplug tips wet, or dry,..??
What carb,..?? 2bbl, or 4bbl,..??
If the distributor has points,..?? Change 'em, or atleast fule 'em,.....

 

[Xlanci]

Where are you checking for spark?
If checking at the coil wire, see if the rotor is turning

I first checked with spark plug inline tester perfect spark then tried old fashion way just grounding the plug and it was a weaker looking spark but was sparking from wires and from main coil as well as the rotor i know is moving cause I was checking the rotation

 

[alldodge]

Edit: wet is no good

 

[Xlanci]

Ayuh,..... Welcome Aboard,..... Are the sparkplug tips wet, or dry,..??
What carb,..?? 2bbl, or 4bbl,..??
If the distributor has points,..?? Change 'em, or atleast fule 'em,...

Thank you happy to be apart of the community and the plugs are wet and it’s a 2barrel carb it does have points I couldn’t locate a new one locally so I sanded off any corrosion and used my feller gauge to re gap it

 

[Xlanci]

Edit: wet is no good

I tried useing starting fluid while cranking it and manually adjusting the fuel intake and no pop or misfiring at all as if the coil is disconnected but it’s not

 

[alldodge]

If the carb is flooding then it will have a hard time starting. But normally there is at least a backfire.

Stick a white or light color rag in the throat of the carb and then pump the throttle. Pull the rag back out and smell it, see if it smells like gas. It also should not discolor the rag

Trying to find out that maybe its mostly water

If its water the wet on the plugs would also look like its beading. If is gas it would coat it even

 

[Xlanci]

I thought the same thing so I unplugged the fuel completely the manually dripped fuel down the carb and nothing

 

[alldodge]

Air, fuel and spark = bang
Something is not there, maybe bad wires or something else

 

[Scott Danforth]

use a dwell meter to properly set points. feeler gauges only get you close

 

[Xlanci]

use a dwell meter to properly set points. feeler gauges only get you close

I went and tried to get one but the auto parts store said they never heard of it lol but eaither way whether it’s correct or not it should still make some noice or pop or any sign of ignition right? That’s where I’m really stuck it doesn’t make sense for it to just do nothing but crank

 

[Xlanci]

Air, fuel and spark = bang
Something is not there, maybe bad wires or something else

Yeah i know that’s why I’m so stumped and I swapped out some for sure good wires with those and still nothing

 

[Scott Danforth]

I went and tried to get one but the auto parts store said they never heard of it lol but eaither way whether it’s correct or not it should still make some noice or pop or any sign of ignition right? That’s where I’m really stuck it doesn’t make sense for it to just do nothing but crank

if your dwell isnt right, it wont do a thing. verifying dwell is the only way to verify your points are working correctly and you are getting proper saturation of the coil. the use of the meter will also tell you the condition of your condenser (capacitor)

Autozone, Advanced auto, pep boys and o-rileys are not auto parts stores. they are a glorified walmart autocenter. you need to vet your parts store. walk in and ask for valve cover gaskets for an SBC. if the person behind the counter asks "perimeter or center?" they are worthy of buying parts from because they know just a little about mechanical things. if skippy behind the counter asks "year, make model?" walk out because he wont know anything and his computer terminal screen is useless. Go to Napa. they may not have a dwell meter in stock, however most know what one is and tell you when it will arrive.

 

[Lou C]

I have the same engine, owned it about 20 years now and it’s always been a reliable starter as long as the ignition is maintained. The Prestolite distributor is very simple to work on. You need a tach/dwell meter and a timing light to get this working reliably. The dwell must be at least close to right and points not burned. Get an Actron engine analyzer and learn Stone Age auto tech 101, Kettering Ignition Fundamentals. Then just check the points every season and replace when they start getting burned. A bad condenser can also cause a burning points issue.

 

[Lou C]

I went and tried to get one but the auto parts store said they never heard of it lol but eaither way whether it’s correct or not it should still make some noice or pop or any sign of ignition right? That’s where I’m really stuck it doesn’t make sense for it to just do nothing but crank

They are just parts pushers with no knowledge!
Dwell must be correct for the primary & secondary ignition system to develop the 25,000 bolts to fire the plugs.

 

[alldodge]

Not arguing with anyone that dwell is the best way, its not needed to get it to start. Doesn't need to be exact to get the motor to run. Something is missing

 

[Xlanci]

Not arguing with anyone that dwell is the best way, its not needed to get it to start. Doesn't need to be exact to get the motor to run. Something is missing

That’s what I kinda figured so do you know what I might be missing here

 

[alldodge]

Nothing shows up.
Your getting spark on all cylinders at the plugs and its white or blue.
Compression is good (130 or more)
Motor is turning over fast enough (at least 300 rpm)
Starting fluid does not help with fuel turned off

 

[Xlanci]

Nothing shows up.
Your getting spark on all cylinders at the plugs and its white or blue.
Compression is good (130 or more)
Motor is turning over fast enough (at least 300 rpm)
Starting fluid does not help with fuel turned off

I am getting spark through a
lol cylinders and when I test it with a inline tester it’s blue but when I do the old fashion way it’s a weaker spark like orangeish abd yes the compression is 135 all around imma try hooking up my jump box for some extra juice and use gas down the carb instead of starting fluid abd see what happens