Yanmar starting problem

[Cloven]

/forums/images/graemlins/confused.gif Engine - Yanmar 2GM20F circa 1996 but not put into service until 2004. Very lightly used, probably less than 200 hrs.

Problem is when starting, sometimes it starts first push of the button. Sometimes when the button is pushed the water/oil/charge lights dim but there is no response from the starter or solenoid and it takes another one or more (up to 5 or 6) pushes on the button before it starts. However, it has always started eventually. Once the starter engages, the engine starts immediately and once started never misses a beat. One last thing, it usually starts first time from cold but problem seems to be worse when engine has been run but then maybe cooling for an hour or two. (This may be a complete red-herring but it seems to be the case).

OK - had it looked at or considered by three different mechanics. First reckoned it was a "sticky" solenoid and stripped same at considerable cost. Seemed to help initially still same problem. Problem here is that I can't say for certain that this treatment helped. Second mechanic reckoned to leave it alone as it starts eventually. All well and good but recently I was in an F5 & big swell about to drop the main before entering a marina and it took 4 or 5 pushes before starting. Third mechanic reckons its an electrical problem and may be a poor contact somewhere along the system so there is a voltage drop when pushing the button.

I would appreciate the views of those forumites who know about these things.

Thanks in anticipation of any help.

 

[KenMcCulloch]

Dear Dave
I recently resolved similar problems with my 1GM10. The eventual discovery was that the battery isolator switch was failing. There is some evidence that the solenoid may be slightly sticking as well which compounds the problem and the diagnosis. I am not an engine expert but responding because the symptoms sound so very similar to my own recent experience. It was only when the battery isolator switch failed completely that I was able to sole the problem. Starts reliably every time now.

Good luck

 

[Richard10002]

[ QUOTE ]
Third mechanic reckons its an electrical problem and may be a poor contact somewhere along the system so there is a voltage drop when pushing the button.

[/ QUOTE ]

No expert, but sounds favourite to me - I'm wondering why he didnt trace the supply to find the poor contact/s?

presumably this is fairly simple for someone who knows what they're doing armed with a circuit tester thingy?

 

[savageseadog]

Suggest you put a meter between the engine block and the output from the solenoid. If it reads 12V when you press the starter and nothing happens then something is wrong with the starter, If you see a small voltage then something's wrong with the wiring.

 

[toastie]

I had remarkably similar symptoms and investigated the same suspects. Finally I discovered the starter motor was rusted up. I was amazed that it had turned at all. Replaced it - problem cured...
Good luck.

 

[oldharry]

I would be looking at the solenoid first, particularly if it is the 'pre-engaged' type which very often does not respond when it is starting to fail.

Battery switch contacts failing is also another culprit, as already suggested.

Intermittent bad contact on both live and return cables: Get a digital test meter (£5 - £10 from Halfords if you dont already have one). Testing is quite simple. Set the meter to its 20 volt or thereabouts range. Connect the probes between the battery + terminal and the solenoid connector. You should not get a reading much over .75 volts when the starter switch is operated. Try again with the probe to the starter motor + contact. (take care not to short anything) Now do the same from the Neg battery terminal to a clean metal part on the engine itself. Again anything much over .75 volts is suspect.

If you get a higher reading on any of these tests, then you have a bad connection somewhere, and must go round cleaning it all up.

If the meter remains at zero at the starter terminal when you hit the start button, but there is a reading at the solenoid batt + terminal, then the solenoid is faulty. There will always be a small voltage across the terminals.

Wonder why your electricians didn't do this simple 'voltage drop' test?

 

[CLP]

I had silimar problems with my 2GM20F up till 2 years ago. Several people had checked terminals, starter etc but no particular problem was found. My own suspician was that the batteries might be showing their age and just not retaining enough charge. I installed new batteries of which one is dedicated for the engine alone, and fitted an Adverc charging system. Since then the engine has fired up without any problems.

 

[Topcat47]

Check the starter button switch too. Contacts can get corroded very easily and that also leads to hit and miss starting. I cleaned the terminals on mine with wire wool and WD40. It made a difference.

 

[tyce]

[ QUOTE ]
Check the starter button switch too. Contacts can get corroded very easily and that also leads to hit and miss starting. I cleaned the terminals on mine with wire wool and WD40. It made a difference.

[/ QUOTE ]

wise words from topcat, had it happen on my last hunter and same problem reappeared on the boat i have now, five minutes with wd40 and job done.

let us know how you get on.

 

[awol]

I've got exactly the same problem and have never found the time or inclination to go searching for the cure. My solution is, if the button won't do it, stick a big screwdriver across the solenoid terminals - works every time!

 

[jfkal]

All my Yanmars had that (new and old). As yours, never failed to start at the end. A bit nerve wrecking but seems to be nothing serious. A seasoned engine mechanic told me not to bother "That's the way they are" .

 

[thalassa]

[ QUOTE ]
All my Yanmars had that (new and old)

[/ QUOTE ]

Count me in that club...Needs up to five pushes when hot..., always starts.

 

[Burnham_Bob]

i've got a 1gm 10 about five years old and a couple of times i've pressed the button and nothing happened..pressed it again and the starter motor kicked in......it doesn't worry me now..........but the first time it happened i could see the pound notes flashing before my eyes as i contemplated a repiar......

i think the solenoid sticks occasionally.....but press 2 or just holding the button down cures the problem