My first experience with hydrolock

[Bt Doctur]

Put a socket and ratchet on the crankshaft bolt and see if you can spin the engine manually..... That will let you know if you have an issue with the motor being locked up...

NEVER EVER DO THAT

 

[R055]

NEVER EVER DO THAT

Excuse the noon question but why can't you turn the engine manually? Or is that only if hydro locked?

 

[Fun Times]

Excuse the noon question but why can't you turn the engine manually? Or is that only if hydro locked?

While some may have been able to successfully turn the front crankshaft bolt without breaking/snapping the front crankshaft bolt in half in the past, it is a very dangerous process step to do as the probability of snapping the bolt is very high especially if the engine isn't truly turning over with the engine starter.... Though you really shouldn't, If or when doing so, Extreme Caution has to be used with how much hand torque you can apply to a normal working engine with the spark plugs removed... The bolt would need to be turned with thoughtfulness care and no forcing can be involved. Very easy slow steps as the engine tries to turn and you need to stop when the engine stops on it's very own with each turn cycle you try to go through is about the best way to try and explain it over the internet. It's a feel thing for sure to try and that is still a no guarantee at all that you still won't snap the bolt even on a known good turning engine as the bolt is already at the point of feeling like it's going to snap as soon as you start turning it.
If the bolt breaks, you may end up having to remove the crankshaft from the engine block.
The majority of us here that posts often on iboats does not recommend turning the bolt and it's just easier/quicker to say don't do it kind of like mentioned by Bt Doctur.

You might want to try adding some marvel mystery oil in each of the cylinders first be fore turning anything more.

Good luck.

 

[BugsyK]

There is a slave solenoid on top the motor. It has four wires on it, you want to jump across the two large terminals on top. Once lumped the starter should engage and crank the motor.

So I can just jump across those 2 terminals with a screwdriver. Does that bypass the ignition as well or will I need to turn the ignition on?

 

[alldodge]

Yes, jump with a screw driver will cause the motor to turn over IF the starter is not bad.

The key switch does not need to be turned to ON for this to happen, but the key does need to be turned to ON if you want the motor to start and run. The key turns power on to the ignition system. Without the key the start should crack but there will be no spark

 

[BugsyK]

Same thing a click when the screwdriver touches both terminals.

 

[alldodge]

Same thing a click when the screwdriver touches both terminals.

If you don't have a bad connection on your starter then you have a bad starter. Suggest pull it off and have it tested at the local auto store. Only issue is they can connect it and cause it to spin but cannot load test it

 

[BugsyK]

Ok, thanks. I was really hoping it was the slave solenoid. I've replaced the starter on this boat before and its do-able but kinda sucks.

 

[alldodge]

You can start with the battery cables.
You can also jump the starter with a screw driver between the small post closet to the motor and the large top terminal

 

[BugsyK]

No Title

Well, this would be the problem. The housing broke off the starter and was laying against the flywheel. Now, I'm not sure how to wire the new starter up. The old starter has a black cable coming out of the starter and attaching to a terminal on the solenoid. The new one doesn't have the cable coming out of the starter. Photo's attached.

 

[BugsyK]

OK never mind that question. After a closer look I see that cable coming out of the other side and much smaller on the new solenoid. The new starter is in and wired up. Should I put some marvel mystery oil in the spark plug holes before I attempt to turn it over?

 

[alldodge]

Should I put some marvel mystery oil in the spark plug holes before I attempt to turn it over?

Won't hurt, but could use any oil or just spin it with the plugs out

 

[Fun Times]

Spin it with the plugs out

+1, For the first engine spin/turnover since not really knowing exactly why the engine locked up, broke your starter housing, had water on the spark plugs, possibly already having internal engine damage, It would be best to have the spark plugs removed to see if the engine will spin at all and let you hear how it seems to sound during cranking...

Yes any oil will do and honestly should be added due to unknown damage inside the cylinder walls, etc.. Marvel mystery oil is usually considered a good go to oil for situations like this.

 

[BugsyK]

Thanks for all the input. The motor spins freely without any crazy noises with no spark plugs in. I'll put some oil in the cylinders tomorrow and put the plugs back in and see if it fires. If it starts I'll change the oil and do the suggested fog procedure. Anything else?

 

[BugsyK]

Hmmm... put oil in the cylinder heads, plugs back in and try to crank just clicks. Take plugs back out, turn key just clicks. Battery appears to be fully charged. So, to recap: Took plugs out motor spins. Put oil in plug holes, put plugs back in, starter clicks. Took plugs out again, starter still clicks. New Mercruiser starter, battery fully charged.

 

[alldodge]

Did you clean the battery cables both sides and both ends?
If yes, then see if you can jump the starter across the larger terminals of the slave solenoid, or at the starter between the small terminal closet to the motor and the larger terminal with the battery cable attached at the top

 

[Fun Times]

At this point it sort of sounds like either your starter and/or starter solenoid went bad...Again..., The mercruiser slave solenoid on top of the engine is bad or the engine has internally seized up do to the hydrolocking event along with possible continued cranking over the engine with the found water on the plugs/in the cylinders.

As a bypass test, try jumping the Yellow with Red striped wire with a good 12 volt wire both at the starter and slave solenoids to see if the starter will spin at all.

In case it's an electrical problem, Here's a guide of the starting circuit,
http://www.justanswer.com/boat/7s0n5...agnum-mpi.html.

 

[BugsyK]

No Title

Cables are clean, I did try to jump the slave solenoid on top of the motor with a screwdriver and it clicked but louder than with the ignition. I think I can try and jump the solenoid on the starter I just want to make sure i'm doing the right thing. Heres a photo of the starter. I guess the purple wire doesnt connect to anything.

 

[BugsyK]

No Title

for refernce purposes this is the motor and here's the battery.

 

[Fun Times]

In the first photo in post 38, I can see the purple wire to the ignition coil is not connected. It needs to go to the + side of the coil. Also be sure there are 2 gray wires at the - side of the coil and the nut is tight.

The photo of the battery, mostly on the ground/black cable end connector I can see some corrosion buildup. Remove the cables and clean the connectors with a wire brush or steel wool. But do both battery cables then follow the black cable to the rear of the engine and ensure it's clean too.

The purple with yellow wire is part of the power system for the ignition system for things such as the fuel pump while the engine is cranking over... It needs to be connected to the/a smaller starter terminal.

Here is a diagram of how your starter should look connected, http://forums.iboats.com/filedata/fe...8&d=1422407474
The purple wire connects to the lighted colored goldish threads just beside the black cover disk that's on the white 90 amp fuse.