5.5 Onan, sounds like a machine gun when I hit the starter.

[tenn_vol_]

First thought it was low batters voltage.
Not to be my luck as it has 13.5 volts right at the ginny.
May be the starter/solenoid is locked up, or checking
other threads one guy said he rotated the engine at the
crank and the engine started.
An checking other threads, said the Onan has to be dropped
to access the starter.
Is the starter/solenoid all in one case, or is the solenoid
located off the starter.
Also how can I rotate the crank by hand or whatever else?

Thanks for any help.....tenn.vol.

[Oldfordman]

In my early years I worked in a gas station. Lost count of the number of people who would have cars towed in and tell me "Needs a new starter", "needs a new battery", etc.

I also lost count of the number of times I would merely remove the battery cables, scrape both the post and inside of clamp with my trusty pocket knife, re-attach, then hit the key ----Vrooom, engine started.

Got a call from my Mother one time. Her husband was in the hospital for surgery and she had their MH home parked at the hospital. She couldn't start the generator and lights went off when she tried.

Same thing. Battery cables were so corroded between inside of clamp and post it was amazing that the lights even worked.

Second most common issue from my early service station days? The ground cable, where attached to the engine, was loose as a goose. I began to wonder if anyone had ever heard of lock washers.

Anytime an electrical connection gets hot and then cools, like a ground cable attached to an engine block, or battery terminals that are subjected to several hundred amp currents for short periods of time, REGULAR maintenance is a must. Clean and tighten. Amazing how much more electricity batteries will hold too as any resistance at the connections will signal the charger that they are full, prematurely.


Lastly, a good test of battery and ground connections is to hold one lead of a multimeter to the center post of a battery connection and the other to the connector itself. Remove spark plug wire and crank engine. Measure voltage drop across the connection. It should be less than .1 volt. Repeat at ground connection as well as solenoid connection. People might be shocked at how much voltage loss their conndections have when cranking the genset due to improper (or total lack of) maintenance.

[tenn_vol_]

Chris B, if I remember correctly, the Onan engine is supported on
3/4 coil springs.
Wolfe10, That was going to be my next move if not to take battery
out and get a load test.

I did find the problem, a loose + wire on the last 6 volt battery.
loose after 5 yrs. then just one day it shows up and runs me around
in a circle.

Now a NEW problem, I have NO 12 volts in the camper...unless the coach
is plugged in to 120 volts.

Got a clue, as I do NOT hear the relay activate when I plug and unplug
the power cable into 120 volt line.

I found the loose wire when I touched a meter lead to the + post
and saw a spark come from post.

Thanks all for the help ....tenn.vol.

[wolfe10]

Pull your car/toad up next to the generator. Carefully attach jumper cables to the positive lug coming in from the coach battery and a clean piece of metal on the generator.

Symptoms change???

[CA_Traveler]

Measure the cranking voltage at the battery posts (not the terminals) and if it's 10V with a charged battery then you know the problem. If OK then measure from frame ground to gen electrical ground to check that connection.

[Chris_Bryant]

tenn.vol. wrote:
Have a 13.78 volt at the ginny, and the case is screwed
to the MH chassis.

Keep in mind the genset is isolated by rubber mounts inside the case- the only ground is a ground strap (and the 120 volt ground)

[MEXICOWANDERER]

Unfortunately, the proper way to diagnose this seems to be elusive according to the OP. This is yet another area in which a digital voltmeter would prove to be useless (the other is magnetic distributor pickup analysis).

If "dropping the generator to remove the starter motor" is the question, then access to starter motor electrical terminals is difficult if not impossible. And without that access, it's a matter of time-consuming and frustrating process-of-elimination.

Hah! I'm playing the part of the-hypocrite.

I would like to find two large face, perhaps 2" scale analog DC panel meters that I can sink into some wood. One a 3.0 vdc, the second, a 0-15 vdc. For checking distributor pickups I suppose I could fashion an LED to pulse, but I checked Crompton Meter Master for large face DC meter and nearly fainted. Same thing for a Triplett analog meter.

Do they still exist? Larger than pocket-size analog multi-meters? I do not want to have to carry eyeglasses for simple diagnostics on a car.

[tenn_vol_]

Have a 13.78 volt at the ginny, and the case is screwed
to the MH chassis. The voltage will drop quickly to 10 volts,
as would be expected if something is locked up. ANd a long
shot would be a weak 6volt battery, that are 5 yrs. old.
I hate to take them out and have them load tested, but that
will be easier than dropping the ginny to find out it is not
that.

Thanks for the suggestions...
I dropped dthe ginny 6 or so yrs. ago, as the variable
clutch/pully had locked up and broke a belt.
But we have both aged out, so I gotta take it to Gen. shop.

tenn.vol.

[azrving]

Dirty/bad connection?

[Chris_Bryant]

Make sure the ground strap to the genset is OK. I like to hook a jumper cable to the frame and genset just to make sure.

[eHoefler]

Battery is dead or has a dead cell. Check the voltage while cranking, you will find it will drop out like a rock.

[MEXICOWANDERER]

Some ID would be most helpful