Genset not starting, just buzzes

I have an older 8kw Onan MDKD. When I push the start button all I get is a buzzing sound on the control box end, below the control box, opposite the starter motor. Thought the noise was coming from the control solenoid but replacement did not solve the problem. Buzzing is from below the control box.

My second genset uses the same batteries and it starts fine. Smart Charger not indicating any problems.

In Bradenton but headed to Punta Gorda and will be anchoring a bit over the next 10 days, so need the genset.

Any thoughts? Or the name of a good gen tech in the SW Florida area?

Happy Holidays!

Possibly remove, clean and check cables and ends. Bad battery or wiring setup is my first guess.

Is the battery sitting at around 13+ volts? If yes, what is cranking voltage at starter?

MDKD has a rather bizarre control system. I have an ex-marine MDKD in my shop for shop/house hurricane backup and sometimes it won't start. Flip lid off the control box and while holding start, whack the solenoid in the box and off it goes. Sometimes also have to shove the shutdown solenoid. Also had wire screws get loose on control board, snugged them up and all was well. Still have to whack the solenoid sometimes. But once running it is rock solid, running for weeks on end.

First thing is put a volt meter on starter batt terminals and watch meter when you hit start. Could be as simple as a crappy connection. See what the volt drop is.

Also the fault breaker on the face of the control box can trip, but not pop out the button. Fixed a few of these by whacking the box next to the button with the handle of a screwdriver. Button then pops out, and can be re-set normally.

Seems like this post used the word "whack" quite a few times!! Well, what ever works!!!

Almost certainly a poor connection, probably a ground. Check and clean them. Perhaps try a jump box. Sometimes this works but it is not 100% .

A wooden mallet 'whack" on the starter often reveals a bad starter.

pete

Could be a stuck starter solenoid. Happened to my Onan at the beginning of last summer.

In my case it was hard to reach but I managed to loosen it by hand and added some WD40 to the piston.

Did the whacking. 13+v at the starter. When I jump the start solenoid it just clicks. No start motor turning. Next step looks like replace the starter. Kubota engine so replacement available. (unlike my other genset which has a Cummins which has parts that are almost always obsolete)

Are you checking volts at starter when the starter solenoid is energized? Key part of that.

We had a similar issue and replaced the glow plug which seemed to fix things. Could also be stuck solenoid which we also experienced. Generator is my biggest headache