Onan woes (1 Viewer)

WinnietheBrave

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I beginning to fall out of love with my Rv, it has more pains than pleasure lately.
My genny did work, was fine the last time it was run. I know they can be a bugger to start if left for a while, so the last attempt I tried till the battery was failing. ( not continuous ) the issue I have now is that it won't even turn over, all I hear is a sort of click/clunk as if the starter is jammed.
Anyone have an idea where to begin?
 

Heyupluv

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I beginning to fall out of love with my Rv, it has more pains than pleasure lately.
My genny did work, was fine the last time it was run. I know they can be a bugger to start if left for a while, so the last attempt I tried till the battery was failing. ( not continuous ) the issue I have now is that it won't even turn over, all I hear is a sort of click/clunk as if the starter is jammed.
Anyone have an idea where to begin?

I am not a RV man but most engines are the same

Hi.... normally when you get the click/clunk it is battery flat..bad battery connections,,,,,solenoid....starter dog/spiral/starter ring.......
If it was me start simple...fully charge the Battery...and make your connections are ok.....try that...make sure your petrol is switched on and you have some in the tank..clean you spark plug or put new one in...then if it does not work check the next item etc....if when running it sounds rough, stops and starts...then clean Filter, clean carb, clean jets...is the choke working ok...

Mel:thumb: good luck

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scotjimland

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As said, battery must be charged, check voltage , if it is 12v or lower it is dead.. a fully charged battery should read 12.6 - 12.8v

If ok, then check: battery connections, earth strap and starter solenoid connections ... remove and clean if in any doubt..

Rather than copy/paste, here is the Onan genset trouble shooting guide .
I would print this out and keep for future reference ..

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chatter

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not having one of these onan gennys but seem to remember from conversations with people that you need more than a quarter of a tank of fuel and if lower than that they wont run, they are so designed so that the genny doesnt leave you with no fuel in the middle of nowhere so to speak.

i really do start with looking at the simple/easy things
 

scotjimland

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not having one of these onan gennys but seem to remember from conversations with people that you need more than a quarter of a tank of fuel and if lower than that they wont run, they are so designed so that the genny doesnt leave you with no fuel in the middle of nowhere so to speak.

i really do start with looking at the simple/easy things

indeed, but it wont turn over .. so it's not fuel starvation ..
the issue I have now is that it won't even turn over, all I hear is a sort of click/clunk as if the starter is jammed.

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chrisgreen

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you say its hard to start when left for a while?
the first thing i would do is drain down the carb as the fuel might be stale,i have the same problem with my 125 motorbike that i carry on the back of my motorhome,it will not start untill iv got rid of the fuel that has sat in the carb for sometime as it has gone stale,once fresh fuel is in the carb it will fire up first time:thumb:
i had a mower given me,as the guy could not start it after it had layed up over winter,i did no more than drained the stale fuel out and that mower starts and run's perfect to this day:thumb:
 

Geo

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Running Air Con and genny once a month for about 1/2-1 hr is best practice
Do I do it No:RollEyes::Blush:
 

Snowbird

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If the RV is diesel its more than likely the genny is LPG, if the RV is petrol then the genny will be petrol.
On the odd occasion that I have had this problem its always been the starter solenoid sticking. A quick fix is get under it with a hammer and give it a few gentle taps.
I had a single cylinder Onan once that had a bleed button on the LPG regulator which you had to press in after it had been standing for some time.
My diagnosis is dirty contacts or faulty starter solenoid.
Stick with it, its all part of the joys of RV ownership. You got it so you gotta fix it.

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Oct 15, 2007
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....and check the plug gap once the cranking issues sorted, 18thou not 25 as it is for petrol, as I seem to remember your a diesel engine therefore LPG gen, as Dave pointed out above:thumb:
 

chrisgreen

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it is a lpg:thumb:
please ignore my post above as it totaly useless in this case.

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Hayleylulu

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try a long screwdriver a cross the solenoid a stater to see iv it turns over its worked for me on some of my cars

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simon_simon

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My onan fix

Like you I had problems with my Onan, used to be a pig to start especially after a period of non use, then failed to start at all. Found a couple of reasons for this, first these take a good battery to turn over, a battery that would spin a 5.7l chevy over had problems turning the genny over, against my better mechanical sympathy by holding the starter button in it would push it gradually over tdc and then proceed to spin away.
Also found the fuel pump would only work if you bashed it, I guess the starter/engine vibration had been keeping it pumping till it expired terminally, I found this by fitting a see through filter which showed the lack of fuel. the duff pump was replaced with a standard generic low pressure pump from ebay.
Which leads to the last issue which was a jelly had formed in the fuel tank which kept being sucked into the carb, take the carb float bowl off and it was in the bottom and it needed the jets blown out with an air line to remove especially around the electric stop valve, this took ages to find as it was difficult to spot the jelly and it would run for 10 mins and then get refouled up.
Manuals can be downloaded and I was surprise how complex these things are, however the manuals have a good set of diagnostic instructions which got me through the dark periods.

Hope this helps

Simon
 
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WinnietheBrave

WinnietheBrave

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Thanks everybody for the input, well spotted to those who knew it is LPG, me bad for not stating this in my opening volley.
I have a basic mechanical knowledge, but for some reason this LPG issue scares me:Eeek:

I have good batteries, I have full tank of LPG. If I had to have a stab at the problem, I would say the starter solenoid is jammed/buggered, my only reason for thinking this, would be from over zealous starting.

@ Snowbird, this Bleed button on the regulator, tell me more. Is the regulator on the genny or elsewhere?
And you are right, I have it, so have to sort it :thumb:
 

lugnutt

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hi i had a generic in mine it had the same probs as you .to get to the starter motor it had to be removed as no way of geting to it, the cost of a new one was about £250.00 so took it to a place for rewinding but the armature was diferent to english motors and they could not do it scraped it and bought a geni in a frame cut fram down and fitterd into gap cost less than a new starter and not as thirsty as a yank one

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callumwa

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not having one of these onan gennys but seem to remember from conversations with people that you need more than a quarter of a tank of fuel and if lower than that they wont run, they are so designed so that the genny doesnt leave you with no fuel in the middle of nowhere so to speak.

i really do start with looking at the simple/easy things

So if you are already in the middle of nowhere, with no additional fuel available, are you left with a quarter of a tank of fuel you cannot use?:Doh:

Would a reserve valve as on most older motorbikes not be more useful so you can use the last quarter.:Eeek:
 

scotjimland

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So if you are already in the middle of nowhere, with no additional fuel available, are you left with a quarter of a tank of fuel you cannot use?:Doh:

Would a reserve valve as on most older motorbikes not be more useful so you can use the last quarter.:Eeek:

Perhaps you misunderstand..

Unless LPG powered, the genny runs on the fuel from the RV engine fuel tank.. if you empty it your going nowhere .. from the middle of nowhere :roflmto:
 

callumwa

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Perhaps you misunderstand..

Unless LPG powered, the genny runs on the fuel from the RV engine fuel tank.. if you empty it your going nowhere .. from the middle of nowhere :roflmto:

:Eeek:

Perhaps I did.....:Blush::Blush:

The earlier post talk of diesel engine, LPG genny.......... got me all confused.com. ......:Doh::Doh:

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Oct 15, 2007
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:Eeek:

Perhaps I did.....:Blush::Blush:

The earlier post talk of diesel engine, LPG genny.......... got me all confused.com. ......:Doh::Doh:

Typically Petrol engine, petrol generator, diesel engine LPG generator.

Of course to confuse thing you can get diesel engine, diesel generator but that's usually on the BIG buggers:thumb:
 
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WinnietheBrave

WinnietheBrave

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Checked the wires, fuse etc today,it all appears to be ok.
The part that the two big wires attach to, (one from the battery, and the other to the house supply?)I would guess at starter solenoid, well this just clicks/clunks, not continuous just once, It sounds like it's jammed, so I gave it a tap, and just for a split second the noise changed, so I gave it a couple of more taps, I was hoping this may help. Alas no, still just the click and nothing else.:Confused:
One thing I did note, was that both the big cables were getting a little warm, nothing drastic just normal like any battery cable would.

On the up side, my fridge has fixed itself :coolthumb:, maybe it was just low gas level and lack of use?
 

bungle.bear

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Hi,

I am new to this forum, but one of my customers last week said I should checkout Motorhome Fun forum as I am half way though building a motorhome based on a Fiat Ducato panel van.

You may ask what has this to do with this thread? But I am the service manager for Cummins Onan Generators.

The first thing I need to know is the model number of the generator, If it does not crank, it is almost certain to be a electricial problem. I would say poor electricial connection, check the negative connection to the chassis. You can also start the RV to see if the extra voltage aids the cranking.

Anthony
 

slobadoberbob

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welcome to the site

Hi,

I am new to this forum, but one of my customers last week said I should checkout Motorhome Fun forum as I am half way though building a motorhome based on a Fiat Ducato panel van.

You may ask what has this to do with this thread? But I am the service manager for Cummins Onan Generators.

The first thing I need to know is the model number of the generator, If it does not crank, it is almost certain to be a electricial problem. I would say poor electricial connection, check the negative connection to the chassis. You can also start the RV to see if the extra voltage aids the cranking.

Anthony


Thank you Anthony for your post, most Onan generators as you know are on RV's (American motorhomes) there is a sister site to this one.. www.rvoc.co.uk most of us that have RV's belong to the dedicated American site, although we do see the odd european motorhome pop up on there. It is a subscription site.. if you pay and belong to MHF then it costs just an extra £5 to belong to that site as well. Being an RV owner I would of course recommend it.

A lot of owbers are not aware of the amount of fuel needed in the petrol tank (if it is a petrol genny) and as you point out it can be the feed or earth .. I do clean mine on a regular basis.. being located under the chassis at the rear does mean it suffers from rust etc., but a good wire brush soon sorts it.

But your post I am sure will help others.

Hope to hear how you get on with your self build as I am sure others will be.

But welcome to the forum.

Regards

Bob, Sue and Ezzie the St Bernard:thumb:
 

Wildman

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First ensure all conections are clean and tight. Having abused the starter solenoid by continuous cranking you may just find the contactor plate inside has partially melted but no way of telling without opening it up. A replacement started solenoid from a scrap yard is the cheapest way forward. Secondly trying to start with a battery that is almost flat will not put enough energy into the starter bendix spring to allow it to disengage. resulting in the clunk you are getting. you may have to remove the starter motor in order to wind it back manually if you cannot get access to tap it. Once sorted do let us know what you found.

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WinnietheBrave

WinnietheBrave

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Sorry everybody, Im just not getting time these days, still haven't looked at the genny let alone tried to fix it, shame on me I know.
Winnie may be up for sale if I don't start getting some use out of her.:Eeek:
Between work and football and rugby with my son, I hardly get time to cut the grass, so Winnie's not even taking a back seat, more like in the rear locker.
 

Wildman

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Winnie may be up for sale if I don't start getting some use out of her.:Eeek:

wash your mouth out with soap and water young man.Take winnie fishing of a weekend thats the least she deserves, I know its a chore but someone has to do it, and there was me thinking you enjoyed Shepton. The men in white coats will be around shortly as you are obviously not thinking straight.
 
Jul 28, 2010
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I beginning to fall out of love with my Rv, it has more pains than pleasure lately.
My genny did work, was fine the last time it was run. I know they can be a bugger to start if left for a while, so the last attempt I tried till the battery was failing. ( not continuous ) the issue I have now is that it won't even turn over, all I hear is a sort of click/clunk as if the starter is jammed.
Anyone have an idea where to begin?
contact Duncan at ww.starspangledspanner.co.uk
he serviced my onan Genny works like a dream now
he is Nr newark lincolnshire

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