3.0L Turning Over But Not Cranking

[dmetall]

I have recently become a proud owner of a 1993 Stingray 556zp. It has a mercruiser I/O 3.0L GM 4 cyl. I have been around boats for a while but never really worked on one. I got the boat because it sank and have been working on it for a couple of weeks. All of the posts have helped get this far but i think it is time to ask a question. Here is a list of what has been done:

-New starter
-New alternator
-New battery and terminals
-Rewired fuse box
-New ignition
-Changed engine oil and trim oil
-New spark plugs and wires
-Cleaned all connections
-Rebuilt carb
-Cleaned gas tank and installed fuel filter

The problem is that when I turn on the ignition the motor turns but never cranks. There is smoke coming from the exhaust so I feel like there is spark but as I am new to engine mechanics (of this size used too work on dirtbikes) I really do not know where to go from here. Oh yeah I do have the clip in for the kill switch. Please any recomendations would be appreciated.
Thank you

 

[dubs283]

Re: 3.0L Turning Over But Not Cranking

turns over and cranking mean the same thing, the starter turns over the engine but it does not fire/run. this is what you mean?

when you say new ignition, do you mean new switch at the helm or new cap, rotor, points/condenser (if conventional), ignition module (if electronic)

when dealing with a boat that sank, you are on the right track with the electical stuff. it ALL needs to be replaced

verify that you do have spark by using a spark tester at the coil wire, if you do, it could be the timing is off or there is still a fuel issue

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

That is what I meant sorry. I also just meant that it is a new ignition switch. I am gonna go pick up a spark tester. Thank you for your answer.

 

[dtime]

Re: 3.0L Turning Over But Not Cranking

try a small amount of mystry oil in the cylenders they the rings may be stuck also test the compression. you could also try sprayin cab cleaner in to manifold while cranking( not staring fluid)

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

I did put mystery oil into the cylinders and let it sit for a couple of days before i did anything. The engine is carburated so where would i spray the carb cleaner?

 

[dtime]

Re: 3.0L Turning Over But Not Cranking

in to the carb while cranking turn the ign on an use a hand button remote start to turn over the engine

 

[dtime]

Re: 3.0L Turning Over But Not Cranking

be sure to stay away from starting fluid as it can break the rings. carb cleaner is nomore than very high octtang gas

 

[dubs283]

Re: 3.0L Turning Over But Not Cranking

you're still gonna need to replace the coil, cap, rotor, points (if equipped)/all the stuff under the dist cap because it did get damaged/contaminated when the boat sank

 

[DrEvil]

Re: 3.0L Turning Over But Not Cranking

in to the carb while cranking turn the ign on an use a hand button remote start to turn over the engine

Ummmm.... Bad Idea. That is an easy way to blow yourself up or blow your motor up.

Start by checking the obvious.. See if you have spark, then move to fuel... Check to see if the plugs are wet (If so clean/replace them) If they are wet then you are most likely getting fuel. If you are getting spark but no fuel... You can spray a small amount of carb cleaner in the top of the carb to see if she fires. You can also pour a small amount of fuel as well. I would never suggest a steady spray while you are cranking it over.

So it is really that simple... spark or fuel. Check the cap and rotor to make sure they are in good shape, and make sure the plugs are good too.

 

[Bilgamesh]

Re: 3.0L Turning Over But Not Cranking

If you're getting spark and fuel...

Is the choke working on the carb?

Check your firing order to make sure you didn't misplace a couple wires.

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

What is the best way to check to make sure the choke is working?

 

[Bilgamesh]

Re: 3.0L Turning Over But Not Cranking

When you turn on your key, and move the throttle all the way forward, your choke plate on the top of the carb should close, and slowly open as the engine warms up.

It just occurred to me to ask, what is your starting procedure. I know when I was new, I did not know how to start the engine properly. I could crank for days and not get it started. Should be something like this:

http://forums.iboats.com/showthread.php?t=339529&highlight=starting+procedure

Also, can we assume you are running on muffs?

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

yes i am running on muffs! I did not know to pump the throttle a couple of time before starting. I will try that once the new rotor and cap are installed. I just ordered them today. Thank you

 

[Don S]

Re: 3.0L Turning Over But Not Cranking

Try pumping the throttle a couple of times BEFORE you change the cap and rotor. Don't change a bunch of things then try it. You never will know what actually cured the problem.
Chances are, without pumping the throttle a time or two, or what ever it takes, it will be hard to start. That's the way carbs are.
Most young guys have no clue about carbs, because cars haven't had them forever.

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

yeah i dont really kno much about carbs except for a little i gained from working on my dirtbike. thank you

 

[dtime]

Re: 3.0L Turning Over But Not Cranking

Ummmm.... Bad Idea. That is an easy way to blow yourself up or blow your motor up.

Start by checking the obvious.. See if you have spark, then move to fuel... Check to see if the plugs are wet (If so clean/replace them) If they are wet then you are most likely getting fuel. If you are getting spark but no fuel... You can spray a small amount of carb cleaner in the top of the carb to see if she fires. You can also pour a small amount of fuel as well. I would never suggest a steady spray while you are cranking it over.

So it is really that simple... spark or fuel. Check the cap and rotor to make sure they are in good shape, and make sure the plugs are good too.

please explain how puting fuel in the carb and down to the cindlers is a bad idea. if we have no feul we will not have any combustion. maybe im the idiot here but i thought that is what we were tring to achive

 

[alex3012red]

Re: 3.0L Turning Over But Not Cranking

had the same problem on a 4.3 (sank, replaced most electrical cleaned gas tank and carb) wouldn't start I had to change the fuel pump and re-ring engine I didn't have enough compression on cyl. good luck

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

Hey guys i know it has been a while since an update but i am still having the same problem with no starting. I got in a car accident and am just starting to work on the motor again. I just put in a new ignition coil and still not getting the motor to start. With this motor is the intake manifold and the exhaust manifold the same piece? There seems to be a lot of rust in the exhaust mani. would that be something i would need to check.

 

[T-Bone Coug]

Re: 3.0L Turning Over But Not Cranking

Are you getting spark, and are you getting fuel? You have yet to answer either question. Until you do, you are just throwing parts at it.

 

[dmetall]

Re: 3.0L Turning Over But Not Cranking

Sorry I am getting fuel and spark. I am not trying to just through parts at it the boat was pretty old and underwater so i figured that at least i would need to replace the electrical stuff.