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I have a 1983 F25. I'm not sure if the engine was an original installation or was installed later, seems a little hackneyed to me but that's not the problem. It's a Yanmar 6 and I'm having two problems. First of all, when the key is on and the alarm is going off, I wait for about 20 seconds for the glow plug to do its' deal before hitting the start button. Intermittently, it sometimes starts on the first push of the button. Howevver, sometimes nothing happens other than the lights on the panel dimming. I turn the key off and on a couple times and eventually it starts. Does this sound like a starter or battery problem?

Secondly, I noticed last night that with the engine idling at ~ 10k RPM's, one of the lights on the panel was flashing, the symbol on the light panel is a small lightning bolt. I increased rpm's and it slowly went away. I dont' have a dial for the battery charging power, I'm not even sure if the alternator is charging at this point though the batteries seem to be just fine.

So, my question is, any idea on why the starter is not working the first time (other than maybe the glow plug hasn't warmed the engine enough)? Any idea why the light on the panel would flash?

For your problem #1, do you hear anything click when you push the button to engage the starter (when nothing happens)? If not, I suspect that the corrosion has formed on the connectors from the panel to the starter and enough voltage drop occurs to keep the started solenoid from engaging. I had the same problem on my Yanmar 3JH and it appears to be a common problem. I would clean up all of the connections and if that doesn't do it, install a smaller relay near the starter that provides power to the solenoid. I had to do the later and it works like a champ now.

I don't have a clue what the lightening bolt symbol means, but if you're really idling at 10K RPM, I suspect that it means that there's a guy in you engine room yelling "Captain, I think she's going to blow!"

-- Geoff

Sorry, I probably didn't state the idle speed correctly. It idles ~2500 rpm, but at that speed it is loud and pops a lot, I goose it to 10k to smooth it out and charge while I fiddle around on the boat. That's why I'm wondering if it isn't charging correctly.

I don't want to drag this down a rat hole and keep someone from really answering your question, but most diesels that I know of top out at around 3500 RPM and idle around ~700 RPM.

-- Geoff

Jeff is correct, 700-1000rpm idle and 3500 max rpm. I would first verify battery is fully charged and good. Turn on all lights and electronics to load the battery and measure the battery voltage. Should be at least 12.3 or more with all load running. If battery is good turn off load and watch battery voltage as you try to start. Should still stay above 12.0. If voltage drops I would take battery to a Pep Boys or West and have them check it. They can tell charge state and load capability, usually for free.

Once battery is good and charged if still not starting work thru all electrical connections, clean and tighten. Don't forget ground connections. I had a starting relay with a poor ground to engine that had same symptoms as you. If still no go confirm starting relay (if you have one), then starting Selonoid operations. Good luck

All good info, thanks. And of course, I was off by a digit on the RPM's but it's always good to be accurate.