Turn key, push buttons, and nothing

[Old Swampy]

My Yanmar 2gm20 wouldn't start, and I found that, if I tried pushing on various parts of the starter button, I could get it to start. A new starter button got rid of my starting problem. Now my wife can start the engine.

[Taughtline]

If it's a corrosion issue of any kind, know that it doesn't just start/stop at a connection. It can contaminate an entire wire. I had some favorite 10g wire I used for several applications. Then discovered that the wires were corroded all through the cord. And this was fresh water environs. All electrical wires and connections are suspect. And fortunately, easy fixes.

[zboss]

The starter works. The problem is intermittent, so its hard to say when it'll work or not work. Next time it happens I'll first try to bypass the solenoid.

Do solenoids fail completely or do they die a slow death?

[warrior 90]

Originally Posted by rwidman

And a lot less expensive as well.

Really though, with the information given, it's impossible for anyone on a website to do anything more than guess what the problem is. And, reading between the lines of the original post, I would be surprised if he understood most of the troubleshooting suggestions posted here.

A person who understands an engine starting system and electricity and actually visits the boat would have this diagnosed in fifteen minutes or less. Randomly swapping out parts until the problem is solved could take hours and cost a lot of money.

Or much less

[warrior 90]

Originally Posted by zboss

The starter works. The problem is intermittent, so its hard to say when it'll work or not work. Next time it happens I'll first try to bypass the solenoid.

Do solenoids fail completely or do they die a slow death?

Sometimes You get a warning that You notice when You have to give contact several times befor the click

But usually they just die

[rwidman]

Originally Posted by zboss

Do solenoids fail completely or do they die a slow death?

Either way.

When troubleshooting an intermittent problem there are a few useful techniques:

Wiggle test - wiggle the parts or connections

Tap test - tap it with the handle of a screwdriver while attempting to operate it. For larger items, a small hammer is appropriate

Thermal test - heat gun or freeze spray as appropriate

[exMaggieDrum]

Lots of good ideas here but so scattered as to be difficult to use. First of all, don't start replacing things until you confirm that it is a problem. You'll have new widgets but will be very lucky to actually solve the issue. Second, this kind of thing can be VERY difficult to trace down and fix. You should start with the most likely suspects and if that doesn't sort it out, then go step by step through the whole system.

I am a very experienced marine electrical tech and have troubleshot and fixed hundreds of start "system" issues. Anything and everything can break so any statements to the contrary are just flat wrong.

The numero uno cause of starter problems are wiring connections, especially at the engine, but everywhere too. Check the big wires to the starter (positive and negative) including the negative to the engine block. Check the terminals/crimps themselves. Voltage checks will not tell you how good they are as a really poor connection/path will register good voltage. No voltage means no connectivity at all. Check connections at the battery too, and at the battery switch(es). Loose connections can cause intermittent problems. I've fixed more loose connections/bad terminals than any other issue. Yet this is the easiest thing for the amateur to check. The terminals have to be crimped well and sometimes this is not obvious by just looking. Wiggle. I have had 2/0 wire pull out of starter terminals that were not properly crimped. Check the wiring at the battery too, and at the battery switch.

Then check the solenoid as mentioned several times above. If it clicks then it MAY be OK but at least it is trying. If no clicks you can try jumping around the solenoid to see if the starter works but you best know what you are doing or you can screw the whole works up. I am hoping this is a diesel and not gas because you will make sparks.

If the starter is getting a good juice and the solenoid is working, then it might actually be the starter itself which could have a couple of bad spots on the commutator OR the brushes may be bad. We had a starter that would work some of the time and not others. I went through the entire system and isolated the problem to the starter. Took it to the local dirt-floor mechanic (in Vanuatu) and the said the starter was fine and told me (basically that I was stupid). I took it back and it still didn't work. Well - it just depended on whether the starter rotor ended up after the last start whether it would start or not. You can try whacking it with a mallet to see if that causes it to start. But it could be a sticking or weak solenoid or the same problem I had. Take the starter to a good mechanic if needed.

You might have a "baby" solenoid that is between the key switch and the starter solenoid as well. Solenoids fail all the time. Keep spares if you have this set up. Solenoids don't need as much juice as the starter but they do have to have enough current to operate - not just voltage.

The wiring between the key switch and the start button to the engine needs to be checked too. You can use your Ohms meter to check a lot of this wiring after verifying you have voltage. Voltage is easier to check first. ALWAYS check the ground connections. You need good ground (DC negative) to everything - panel to engine to battery. You can test Ohms on the key switch as well. They routinely go bad. Same for the start button.

Of course, your start battery has to be good as well.

The engine alarm you should hear when you turn on the key switch turns off from an oil pressure switch (normally on). When the engine starts and builds oil pressure it should go off. If no alarm then you have a bad connection or bad oil pressure switch or bad key switch or bad alarm buzzer. The key switch powers the buzzer so long as the oil pressure switch remains on. The buzzer may be used for other things as well but that is the sorta/kinda starter related function.

Good luck. Again - go for the most likely issues first - loose connections, terminals, solenoids, switches. Then go through section by section to track down any other problems but I bet you get it fixed before that - BUT it may get down to that.

Please don't take me apart if I left out something. I did this off the top of my head and just trying to be helpful. It should point you in the right direction.

[zboss]

BTW - this is a westerbeke 46 - mitsubishi block.

I don't think its the starter itself or the solenoid. I had an extra brand new starter and solenoid and, since I had been having these problems for about 8 months, figured that I might as well pull the starter and starter solenoid out and put the new one in while the engine was pulled during our rear oil seal episode this past December. If it turned out that the problem was the starter or solenoid and I had not replaced it, it would have been very difficult to do so after-the-fact. The problem seems to have gotten progressively worse.

I kept the original starter/solenoid as a backup.

So, when this happens again, I'll bypass the solenoid first to see if its reasonable that the problem is likely from the wiring back. I looked up new switches and they don't cost much and are pretty accessible. The wiring on the back of the engine up to the panel is pretty inaccessible without taking half the boat apart. This is why I have been focused on the solenoid and starter, its relatively easy to get to.

When I get back to the boat these next few days I'll try some of the items listed in this thread and see what happens and report back.

- z

[Cadence]

Originally Posted by zboss

The starter works. The problem is intermittent, so its hard to say when it'll work or not work. Next time it happens I'll first try to bypass the solenoid.

Do solenoids fail completely or do they die a slow death?

They can die a slow death. You can usually hear them click. They are no more than a relay with bad contacts and are intermittent.

[leftbrainstuff]

Step 1) Work your way through the starting electrical circuit. Having someone check for voltage drop of each component while you put the starting system under load. This will usually highlight the problem and is a simple test.

Step 2) Sometimes the starter solenoid can exhibit issues which may be electrical or mechanical in origin. Removing the starter or solenoid and bench testing is simple.

As the issue is intermittent an electrical cause is a good first bet. If the issue has some correlation with temperature then a sticky solenoid may be a likely cause.

Just work through the basics to zero in on the root cause.

Sent from my SM-N900T using Cruisers Sailing Forum mobile app

[jimbunyard]

I'm going with first, a bad pushbutton switch, or second, a loose connection at the starter (since you just replaced it).

At any rate, rather than shooting around in the dark, why not start at the source? Next time it happens, make a little tool like the one shown in the first picture, and, with the ignition on, jump the two connections out as shown in the second picture.

Two things should happen, you should get a healthy spark, and the engine should start. If it does, replace the pushbutton. Nothing happens, problem is before pushbutton, probably ignition switch. Sparks but no start, problem is between pushbutton switch and starter motor, get out the test light or voltmeter, and with a friend operating the pushbutton with the ignition on, test every connection, from the pushbutton to the solenoid (in that order), by connecting the test light or meter from the test point to a good ground.

You should get a solid 12.1 - 12.5 volts, or a good bright light, at every connection, if you don't there is an issue at that junction.

[rwidman]

Rather than this:




Make one or two clipleads with two feet of wire and an alligator clip at each end. Useful for a lot of electrical troubleshooting. #12 stranded would be good.

You can buy them ready made at Radio Shack but they are crap.

[zboss]

I already have several wires with clip leads I used for other testing. I'll give it a shot this week.

[zboss]

ok - I believe I have determined it is NOT the start button. I attached my meter to the back of the button and watched the resistance after about a dozen pushes.

What I did hear is a bzzzz bzzzz bzzzz coming from the engine room that I don't recall hearing before.

The start battery I have is of unknown age but the voltage seems to be OK when I turn on the key (more than 12 but less than 13) but its hard to say exactly the voltage.


Maybe I need to test the battery.

[rwidman]

Originally Posted by zboss

ok - I believe I have determined it is NOT the start button. I attached my meter to the back of the button and watched the resistance after about a dozen pushes.

What I did hear is a bzzzz bzzzz bzzzz coming from the engine room that I don't recall hearing before.

The start battery I have is of unknown age but the voltage seems to be OK when I turn on the key (more than 12 but less than 13) but its hard to say exactly the voltage.


Maybe I need to test the battery.

Put your meter leads on the battery terminals and measure the voltage with no load and then when trying to start the engine.

A weak or dead battery is the most common cause of engines failing to start and is the first thing to check.