7500 onan generator only clicks when starting

[StillRunning_60]

Been sick this summer so I never got to start my onan in about 3 months so went out yesterday to start it and only get clicks. I have check batteries and they are charged. Check 3 fuses under the rad cap so out of ideas. As Someone else had this problem.

[Tom Cherry]

32 minutes ago, StillRunning_60 said:

Been sick this summer so I never got to start my onan in about 3 months so went out yesterday to start it and only get clicks. I have check batteries and they are charged. Check 3 fuses under the rad cap so out of ideas. As Someone else had this problem.

FIRST...  Do this.  NEVER depend on the BATTERIES...   SHUT DOWN BOTH disconnects.  THEN hook up an Automotive Jumper Cable between the Positives of the HOUSE and Chassis.  THEN turn back on the switches.  Start the ENGINE.  You need to let it run for 5 minutes.  Probably overkill, but there is a relay that keeps the alternator from charging....  when it starts up....as the Air Intake Heaters sucks up current like Popeye swarfs down spinach.  Once the battery voltage is stabilized in the high 13.'s...

THEN PRIME THE GENNY.  Hold the switch in the OFF position and the light should light up.  Hold that for maybe 20 seconds.  WAIT a minute.  THEN repeat twice or three times more.

NOW....push the TOP of the Genny START switch.  See what happens.  You have PLENTY of power.

NO JOY....then the NEXT TEST.  And this is GOOD PM.  OK... engine off...

NOW....chase down the NEGATIVE behind the Battery Boxes.  PROBABLY TWO cables.  They are bolted (with a NUT on a welded stud) Loosen clean and then retighten.   DO BOTH.  

Next go under the MH to the Genny.  The terminals on the back bottom are SOFT COPPER or BRASS.  SO, you can't torque them like a steel stud.  Loosen each....clean and then tighten...but snugly...  one of our MOST experienced members....twisted his off.  AND WE ALL LEARN.

NOW.....look at the cables.  Chase the Ground to the Chassis Ground.  CLEAN.  AGAIN....this is a common problem and good PM.  Find the Positive.  WHERE it is connected....then clean and tighten.

OK....HIT IT AGAIN....with the Engine Running.  NO JOY...  

This is the LAST TEST.  Batteries OFF.  Pull the Jumper.  Batteries ON.  NOW, take both the Positive and Negative Jumpers and hook them to the Genny's terminals.  THEY will fit....just have to be a little creative.  THEN put the other end on your vehicle.  Start the engine.  Let it run for a few minutes.  NOW try the Genny SWITCH.  If it clicks then.....You have an issue.  

If NOT and it starts.....then you have a bad or high resistance connection.....upstream.  

THIS IS NOT some thereoretical BS.  This is tried and proven.....and I had to LEARN the hard way that a Bad Ground on the HOUSE (mine cranks there) was the CULPRIT.  I had to jump it off when it was hot as blazes and the CG power was below 100 VAC and my surge suppressor was LOCKING me out.

Trust me...  This will work...and the methodical logic of the test will tell you WHERE the issue is.

Let us KNOW.  Good Luck.