engine wont start (mercruser 5.7L
08-31-2008, 02:00 AM
#11
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I have checked the spark only on one plug!
Although I have checked, and cleaned Distributor Cap and Rotor,
the engine has very little run hours, mostly just sitting on the salt water or marina spat.
Then I was told that the gas must be old so I puled out ~ 20 gallons and put a fresh in, and it still wont start
09-01-2008, 06:06 PM
#15
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I understand you have spark, however:
BT may be correct. Try what he says then if nothing still:
1) replace plugs. They can get oil soaked from the fogging you did for the winter. Cleaning won't cure this. New plugs and gap to .035"-.040"
1a) if cap/rotor is electrically eroded, cleaning will not repair them.
2) If still no start check voltage to coil. Should be battery voltage.
3) Do you have a fuel shut off valve ? Did your fuel pump schit the bed ? Carb may still have fuel in bowls (not for long though) and tease you.
3a) Make sure choke is not stuck closed. As mentioned above, putting throttle to WOT should fully open choke. Of course, if engine fires bring throttle right back down. No need to blow up engine on trailer.
4) Do a compression test.
5) Check for nests/animals/insects (ie:blockage) in your fuel vent and exhaust pipes. Damn critters !
6) Check your fuel. Smell with nose and if it does not burn your nose and has almost no aroma, it's weak and won't light.
Had you done anyh other boat (not justg engine) work after winterization ?
BT may be correct. Try what he says then if nothing still:
1) replace plugs. They can get oil soaked from the fogging you did for the winter. Cleaning won't cure this. New plugs and gap to .035"-.040"
1a) if cap/rotor is electrically eroded, cleaning will not repair them.
2) If still no start check voltage to coil. Should be battery voltage.
3) Do you have a fuel shut off valve ? Did your fuel pump schit the bed ? Carb may still have fuel in bowls (not for long though) and tease you.
3a) Make sure choke is not stuck closed. As mentioned above, putting throttle to WOT should fully open choke. Of course, if engine fires bring throttle right back down. No need to blow up engine on trailer.
4) Do a compression test.
5) Check for nests/animals/insects (ie:blockage) in your fuel vent and exhaust pipes. Damn critters !
6) Check your fuel. Smell with nose and if it does not burn your nose and has almost no aroma, it's weak and won't light.
Had you done anyh other boat (not justg engine) work after winterization ?
Last edited by SB; 09-01-2008 at 06:11 PM.
09-02-2008, 02:25 AM
#16
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I understand you have spark, however:
BT may be correct. Try what he says then if nothing still:
1) replace plugs. They can get oil soaked from the fogging you did for the winter. Cleaning won't cure this. New plugs and gap to .035"-.040"
1a) if cap/rotor is electrically eroded, cleaning will not repair them.
2) If still no start check voltage to coil. Should be battery voltage.
3) Do you have a fuel shut off valve ? Did your fuel pump schit the bed ? Carb may still have fuel in bowls (not for long though) and tease you.
3a) Make sure choke is not stuck closed. As mentioned above, putting throttle to WOT should fully open choke. Of course, if engine fires bring throttle right back down. No need to blow up engine on trailer.
4) Do a compression test.
5) Check for nests/animals/insects (ie:blockage) in your fuel vent and exhaust pipes. Damn critters !
6) Check your fuel. Smell with nose and if it does not burn your nose and has almost no aroma, it's weak and won't light.
Had you done anyh other boat (not justg engine) work after winterization ?
BT may be correct. Try what he says then if nothing still:
1) replace plugs. They can get oil soaked from the fogging you did for the winter. Cleaning won't cure this. New plugs and gap to .035"-.040"
1a) if cap/rotor is electrically eroded, cleaning will not repair them.
2) If still no start check voltage to coil. Should be battery voltage.
3) Do you have a fuel shut off valve ? Did your fuel pump schit the bed ? Carb may still have fuel in bowls (not for long though) and tease you.
3a) Make sure choke is not stuck closed. As mentioned above, putting throttle to WOT should fully open choke. Of course, if engine fires bring throttle right back down. No need to blow up engine on trailer.
4) Do a compression test.
5) Check for nests/animals/insects (ie:blockage) in your fuel vent and exhaust pipes. Damn critters !
6) Check your fuel. Smell with nose and if it does not burn your nose and has almost no aroma, it's weak and won't light.
Had you done anyh other boat (not justg engine) work after winterization ?
I have replaced all gauges just like ther were before.
I have replaced Shift Cable, all bellows and gaskets.
I have replaced gas in the tank, and fuel filter/water separator
I have cleaned up the carburetor and replaced ignition coil with spark plugs.
I have checked solenoid, and kill break is working,
It is still not starting!!!
I have ordered the Distribution Cup with router, and spark plugs wires set.
I just can not see the timing to be changed, HOW???
I have replaced the water hoses but not the belts!
If I will screw something up with wiring then there will be no spark!
Oh!
THERE IS THE SPARK, BUT I THING IT IS NOT TOO STRONG!
The spark on the spark plug looks fine, but on the special tester where the minimum spark length should be around 3/16" - it is not present!
It shows up on on the gap distance around 1/32"
So, I am going obsess!
I have 40 years of mechanical back grand in different fields, but this is still amazing to me!!!
There is a gas and the spark, and the timing is untouched , so what a heck is it???
Krzychu
PS
I did not check jet for clogged vents!
Last edited by Krzychu; 09-02-2008 at 02:31 AM. Reason: more ifo.
09-02-2008, 10:14 AM
#17
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You know if I had a dollar for everytime a guy could not get his engine to start, and I jumped in and did what I said above and whala, fires right up.... well, I'd have at least 10 dollars 
Did you try this yet?
BT
Did you try this yet?BT
09-02-2008, 10:28 AM
#18
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If you have HEI ignition and it won't jump 3/16 I would think that is a problem. Maybe you left the key on too long at some point and burned up your coil. At this point you can bring it to a shop, try a new non resister coil or PUNT.
09-02-2008, 01:00 PM
#19
Gold Member
Yes
I have replaced all gauges just like ther were before.
I have replaced Shift Cable, all bellows and gaskets.
I have replaced gas in the tank, and fuel filter/water separator
I have cleaned up the carburetor and replaced ignition coil with spark plugs.
I have checked solenoid, and kill break is working,
It is still not starting!!!
I have ordered the Distribution Cup with router, and spark plugs wires set.
I just can not see the timing to be changed, HOW???
I have replaced the water hoses but not the belts!
If I will screw something up with wiring then there will be no spark!
Oh!
THERE IS THE SPARK, BUT I THING IT IS NOT TOO STRONG!
The spark on the spark plug looks fine, but on the special tester where the minimum spark length should be around 3/16" - it is not present!
It shows up on on the gap distance around 1/32"
So, I am going obsess!
I have 40 years of mechanical back grand in different fields, but this is still amazing to me!!!
There is a gas and the spark, and the timing is untouched , so what a heck is it???
Krzychu
PS
I did not check jet for clogged vents!
I have replaced all gauges just like ther were before.
I have replaced Shift Cable, all bellows and gaskets.
I have replaced gas in the tank, and fuel filter/water separator
I have cleaned up the carburetor and replaced ignition coil with spark plugs.
I have checked solenoid, and kill break is working,
It is still not starting!!!
I have ordered the Distribution Cup with router, and spark plugs wires set.
I just can not see the timing to be changed, HOW???
I have replaced the water hoses but not the belts!
If I will screw something up with wiring then there will be no spark!
Oh!
THERE IS THE SPARK, BUT I THING IT IS NOT TOO STRONG!
The spark on the spark plug looks fine, but on the special tester where the minimum spark length should be around 3/16" - it is not present!
It shows up on on the gap distance around 1/32"
So, I am going obsess!
I have 40 years of mechanical back grand in different fields, but this is still amazing to me!!!
There is a gas and the spark, and the timing is untouched , so what a heck is it???
Krzychu
PS
I did not check jet for clogged vents!
The only thing I can think of, is timing. By reviewing your responses, it seems like that is the only thing you have ASSUMED to be good. I've learned to never assume anything!
You never know. I had a ford 390 once that ran perfect until is was shut off one day, the next day it would not start. Turns out the roll-pin that holds the gear on the dist. shaft sheared, and the timing was off by 40 degrees. Never hurts to check.\
Nick
09-02-2008, 01:29 PM
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I one time flooded an engine so bad it washed all the oil off the rings and created low compression, too low to start. I had to go through each spark plug hole and squirt 10w30 on top of the piston to get the compression back up before it would start.
Do you smell fuel in your motor oil?
Do you smell fuel in your motor oil?
