My boat recently spent 3 months (yes, no typo.....3 months) up on blocks in a boatyard. What a cluster----!! Anyway, when the boat was returned to the water, it would not start, as if the batteries were low/dead. They weren't. The mechanic says that it's either the starter (almost brand new) or the solenoid. My question is, is it possible that the long stay out of water caused corrosion to either cylinders, starter or solenoid that prevented the engine from turning over? Oh, yeah..the engine is a 1987 GM30F.
Yanmar Engine problems.
- Thread starter AllenF
- Start date
Were you present when the boat was put in the water? Use the compression lever and try turning engine by hand. If the engine does not turn it would seem that the most likely possibility is a hydraulic lock caused by long and repetitive cranking while the engine failed to start. With the exhaust port below the waterline if an engine is cranked for too long it can suck up water through the exhaust system. The problem is that water does not compress very much and such a condition will likely break piston rods and pistons. If the engine turns freely then it is likely an electrical malfunction. After making sure batteries are fully charged check to see if the solenoid is making a clicking noise. If it is but the starter is not turning check all the electrical connections for corrosion. Was the starter recently replaced? If it is an aftermarket unit it could possibly have failed and should be bench tested. If the solenoid does not click then it could be suffering from a voltage drop in the wiring or the solenoid has failed. I would cross the solenoid terminals with a screw driver to see if that activates the solenoid and starter. If it does and the engine turns then your problem is in the wiring from cockpit control panel to solenoid. In diagnosing the problem the first step should be see if the engine is turning freely. Eliminate right away or confirm the possibility of a hydraulic lock. The most common occurrence should be a drop in voltage in the starting circuit and there are ways to fix it from rewiring the starter button to adding an auxiliary solenoid. Good luck.
Benny pretty much covered things to try.
In answer to one of your questions, boats in the frozen north are routinely out of the water for 4 to 6 months with (generally) no ill effects.
In answer to one of your questions, boats in the frozen north are routinely out of the water for 4 to 6 months with (generally) no ill effects.
Diagnose the problem first.
does the engin turn at all when you hit the starter?
if no then the engine is "stuck" or the starter is not engaging.
if no turning at all do you see a voltage drop in the batteries when you engage the starter?
a voltage drop would indicate a stuck engine and the starter is OK
no voltage drop indicates the starter is not engaging
if the engine turns at all the starter is engaging and either does not have enough juice or is trying to turn a stuck engine (ie too much load for the starter but it is ok).
we could go on and on but lets try and isolate the system that is not working first.
does the engin turn at all when you hit the starter?
if no then the engine is "stuck" or the starter is not engaging.
if no turning at all do you see a voltage drop in the batteries when you engage the starter?
a voltage drop would indicate a stuck engine and the starter is OK
no voltage drop indicates the starter is not engaging
if the engine turns at all the starter is engaging and either does not have enough juice or is trying to turn a stuck engine (ie too much load for the starter but it is ok).
we could go on and on but lets try and isolate the system that is not working first.
Once hydro locked my 3GM30F by releasing the engine stop pull on the very last 1/2 rotation of engine and then it acted as if I had a dead or low battery. Learned a very important lesson on making sure the engine has completely stopped prior to releasing the stop pull.
Try releasing all 3 decompression levers, 1 for each cylinder and hand cranking 1st, hopefully it will turn a complete revolution without much effort, then try with starter. If it is hydro locked it could clear out the cylinders and allow to start. This should at least rule out if the engine is locked up.
Even though not on a load at least you know the starter is working and the solenoid is engaging.
Jeff
sv LegaSea
2003 Hunter 356
Try releasing all 3 decompression levers, 1 for each cylinder and hand cranking 1st, hopefully it will turn a complete revolution without much effort, then try with starter. If it is hydro locked it could clear out the cylinders and allow to start. This should at least rule out if the engine is locked up.
Even though not on a load at least you know the starter is working and the solenoid is engaging.
Jeff
sv LegaSea
2003 Hunter 356
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All good advice. An easy way to see if you have voltage drop: turn on a cabin light and hit the starter. If the lights were bright as in 'fully charged batteries', and there's great loss of light when you hit the starter it's probably a stuck engine or starter. Turn on several cabin lights and if the first one gets dimmer as the others are turned on, it could possibly mean weak batteries or poor connections. This doesn't tell you much but is a simple way to at least get you started in the right direction.
You could always bypass the solenoid and see if it spins. I've done this on boats and cars. It proves out the engine and starter in an instant. Just put handles from an old fashioned pair of pliers one on each big bolt of the solenoid. Don't be startled, it will spark. Be careful to not ground out the system by touching anything else with the pliers.
I've also used this technique to get home when electrical things go bad.
Ken
I've also used this technique to get home when electrical things go bad.
Ken
when using jeff356's method of hand cranking a 4 stroke engine to clear it you have to hand crank 2 compleate rotations not just 1. 4 stroke, each stroke is 180 dgrees = 720= 2 rotations not 1 to make sure every cyl has been through an exhaust stroke.
and.. to continue to beat the horse, Yanmars are notorious for getting corrosion in the 4 connectors between the power and the start solenoid. Lots of posts here over the years.. A good Yanmar mechanic would jump "hot" on starter (big wire direct from battery or battery switch) to the small "coil" connection..(after pulling the de-compression levers) IF that doesn't spin it, then starter or solenoid or batteries or battery connections..
My first thought is a loose connection. I like the "turn on lights" thing - it would tell you a lot. I wouldn't jump to hydro-lock right away - electrical problems are far more common. But since the GM series HAS a hand-crank and decompression levers, USE them and see if the engine rotates properly.
I'd put a voltmeter on the starter bolt (where the BIG red wire terminates) and ground. You should see full battery voltage (over 12 V). Then try to crank. You should see maybe 8 V. If it stays close to 12V the solenoid isn't working. If it drops way below 8V either:
- Battery is poor: if the lights in the cabin dim a lot too, it's the battery
- Poor connection: if the lights stay bright in the cabin (mine turned out to be the battery switch)
- Something is jammed: if the engine turns over by hand, it's the starter.
Hope this helps
druid
I'd put a voltmeter on the starter bolt (where the BIG red wire terminates) and ground. You should see full battery voltage (over 12 V). Then try to crank. You should see maybe 8 V. If it stays close to 12V the solenoid isn't working. If it drops way below 8V either:
- Battery is poor: if the lights in the cabin dim a lot too, it's the battery
- Poor connection: if the lights stay bright in the cabin (mine turned out to be the battery switch)
- Something is jammed: if the engine turns over by hand, it's the starter.
Hope this helps
druid
We are mostly all aware of the Hunter Malady, you turn the key switch to On, push the starter button and nothing happens. The failure is usually gradual as repetitive pushing of the button usually gets the engine cranking but it can happen of all of a sudden if compounded with a loose or corroded connection. The reason is a voltage drop in the old wiring. If you cross the terminals of the solenoid with a screw driver you will have bypassed the low current starting circuit and activated the high current starting circuit. ( a remote starter button could be connected to solenoid to avoid the sparking) If the starter turns the engine then you know your problem lies with the low current circuit which encompasses the key switch, the starter button. the solenoid and the wiring harness from control panel to solenoid.
if you turn your key and nothing happens at all and you are sure the batteries are up turn your key on and jump the posts on the solenoid if it just clicks hard but doesn't crank pull both starter and solenoid and have them tested if it does not spark at all with screwdriver check wireing and batteries
You should have 0 volts from the red post of the starter to ground before you try to crank, otherwise the starter would be trying to turn. Also the trick of looking at the cabin light brightness will only work if the boat doesn't have a dedicated start battery. Other than that you've got an intersting troubleshooting process.
Nope.
I'm talking about the post on the starter where you connect the Big Red Wire from the battery. The power from there goes through the solenoid to the starter - no solenoid, no starter.
druid