Yanmar 4LHA STZP Starter Motor Click - advice sought

[Seahope]

Hi all,

I am certainly experiencing the frustration of boating first hand. After a successful first trip out on our own imagine my disappointment when we arrived for our second trip out and the port engine no longer starts. I can hear an audible click and the voltage drops a little but no engine cranking. The starboard engine starts fine.

I have changed both batteries as they were the originals and must be at least 5 years old, so I charged them patiently and still hear just a click. Today I was eventually able to find and remove the + and - terminals to the port starter motor and cleaned them both up and reattached, but no still no joy.

I have a mechanic booked to look at this and a few other niggles but this is not for a few more weeks and I am frustrated that in this good weather spell we can't use our new boat. Any suggestions as to what I can try next? I have just dug out an old voltameter from my garage but I am not sure what I should be checking next.

Good luck to those of you able to enjoy Spring on your boats

 

[volvopaul]

Sounds like the solenoid has failed if your getting a click, unless its the relay below the starter motor that clicking but not energising the main solenoid on the starter.

An easy way to check out the starter and auxilary solenoid is to place you volt meter on the cable from the solenoid on the starter and check to see if you have voltage there, if so it may be the windings or brushes, though I doubt that .

That would be my first check if you got me out to the job, assuming you have fully charged batteries and all the simple bits checked out first.

Then if no voltage at that stage, check the other solenoid bolted to the engine to see if thats sending voltage to the main starter sol, all sounds a bit jumbled up but when your there its quite easy.

 

[Seahope]

Sounds like the solenoid has failed if your getting a click, unless its the relay below the starter motor that clicking but not energising the main solenoid on the starter.

An easy way to check out the starter and auxilary solenoid is to place you volt meter on the cable from the solenoid on the starter and check to see if you have voltage there, if so it may be the windings or brushes, though I doubt that .

That would be my first check if you got me out to the job, assuming you have fully charged batteries and all the simple bits checked out first.

Then if no voltage at that stage, check the other solenoid bolted to the engine to see if thats sending voltage to the main starter sol, all sounds a bit jumbled up but when your there its quite easy.

Thanks. I think the click was coming from below the engine so I looked at what turned out to be a relay on a pivot assembly. I had taken off the two main cables and noticed a small wire connected to the engine which seemed loose. As I was tightening this the engine suddenly started
I was glad no parts of my anatomy were near the belts

I somehow managed to bypass something, but I don't know what and am not keen to try that experiment again. I was far too close to the engine for comfort.

As the the small wires on the relay assembly seemed a little dirty I wanted to take them off, but that required me to take off the whole relay assembly as they were only about 5mm, which took much longer than I had expected as access to it was not good. One is a white wire which I am sure is connected to the starter switch and the other is a negative which is connected to the engine. I have reattached everything on the relay assembly to where I thought it was at the beginning. Now there is no click and the engine still doesn't start. There are 13.67 volts across the two small connections on the relay when the engine is attempted to be started and 13.69 volts across the two main cables on the switch constantly.

I have not managed to find the solenoid so I am clearly not cut out for a career as a mechanic I am seriously going to ache tomorrow!

 

[PaulGooch]

I'd say the relay you were poking about is shot. I'd also hazard a guess that when you were messing around with it you shorted the two large terminals together. Two tips that will stand you in good stead on your journey to becoming a fully skilled mechanic :

1) In an emergency, you can carefully short those two terminals together to get the engine started. You appear to have already grasped the concept of not introducing bodily parts into the area of the belts

2) If you don't want to carry out the aforementioned emergency engine starting operation whilst checking the relay, take the negative lead off of the engine battery and secure/insulate it out of the way.

 

[Seahope]

I'd say the relay you were poking about is shot. I'd also hazard a guess that when you were messing around with it you shorted the two large terminals together. Two tips that will stand you in good stead on your journey to becoming a fully skilled mechanic :

1) In an emergency, you can carefully short those two terminals together to get the engine started. You appear to have already grasped the concept of not introducing bodily parts into the area of the belts

2) If you don't want to carry out the aforementioned emergency engine starting operation whilst checking the relay, take the negative lead off of the engine battery and secure/insulate it out of the way.

I don't think I'll ever make a good mechanic

I definitely will take your advice about removing the negative leads off the batteries in future when messaging around with the engines.

Does anyone know where I can get hold of a new relay? A little Googling led nowhere. At least I don't need a new starter motor which is a bit of a relief as Yanmar ones seem eye wateringly expensive, just like diesel these days.

 

[Seahope]

I'd say the relay you were poking about is shot. I'd also hazard a guess that when you were messing around with it you shorted the two large terminals together. Two tips that will stand you in good stead on your journey to becoming a fully skilled mechanic :

1) In an emergency, you can carefully short those two terminals together to get the engine started. You appear to have already grasped the concept of not introducing bodily parts into the area of the belts

Well, attempting today to repeat the emergency start failed. Even when both leads were removed from the relay and directly connected together no action from the starter.

With the main cables removed from the relay I checked the resistance between the two main terminals on the relay whilst the engine start switch was depressed. I was expecting to see the resistance reading drop to zero and it didn't. I found a useful explanation to how relays and solenoids work here if anyone is interested: http://www.1728.com/project3.htm. I am sure that the solenoid is defunct.

The part number for the solenoid is: 2768101-A which still hasn't helped me find one. No manufacturer name obvious, just 'Made in Japan'. I have found a site which has a couple of similar solenoids but not with the right angle as the terminals are 90 degrees away (to the left) from the rubber covered engine mount holes.

The weather looks great for next weekend so I'm hoping some phoning around this week will result in a new part for me to try next weekend. I can now remove and replace this part in less than 15 minutes

If this is not the only problem, then my next plan of attack is to check the live lead from the solenoid to the starter motor in case it has melted or shorted somewhere beneath the engine. It really isn't easy to see where these wires go, so I shall attach a piece of string to enable me to pull the cable back if it is OK. I will have to wait until all the bruises have gone from my efforts yesterday. I am either too old or heavy (or both) to lie on batteries and water heaters without consequences

 

[Seahope]

Starter Relay Replaced - click back

Well, I have just changed the starter relay and the engine is back to making a click

 

[neale]

The joy of having 2 engines is that stuff can be swapped from one to the other, effectively giving you a spare everything without spending any money. Once the obvious stuff has been checked, I would be tempted to whip the starter motors off and swap em over, assuming they are reasonably easy to get too. My money would be on a starter or solenoid fault.

 

[Seahope]

The joy of having 2 engines is that stuff can be swapped from one to the other, effectively giving you a spare everything without spending any money. Once the obvious stuff has been checked, I would be tempted to whip the starter motors off and swap em over, assuming they are reasonably easy to get too. My money would be on a starter or solenoid fault.

Yes and a disadvantage is that there is very little space between the engines and the engines and the sides of the boat.

I looked today at the starter motors and solenoids on both engines. I was totally unable to remove the small solenoid connection as I can't see how to get it off with the solenoid connected as there seems no space/way to do this and I could only find one bolt for the starter motor so I decided not to try to remove it and I know there must be two with the second hidden behind parts of the engine.

Therefore, I've decided to be patient and wait for the professionals to fit me in to their busy schedules. It was very frustrating watching everyone else go out on such a lovely day though and being unable to myself.

Someone managed to install the engines in the boat so I hope it is possible to perform basic maintenance without having to first remove the engines.