onan marquis wont start


vettman74

New Member
Hi, can anyone help me with a few things.I need info or a website on the marquis(bgm).Also I just got this rv and the generator wont start.It cranks ,but wont start at all.I replaced the plugs,air filter,oil change(up at full mark-just a tad under),and replaced the fuel filter.Still nothing.Cranks good from inside,but the switch doesn't work very well from the outside?Any suggestions.I got told to check the coil for power.Need to see a picture possibly to see it,these are pretty enclosed,so you can't see much.
 
G

Guest

Guest
RE: onan marquis wont start

How much gas do u have in u'r main tank?? or do u have a seperate tank for the genny (if u have a diesel coach)???
Also what kind of probs does the outside switch have ???? This may be a prob with the set...
Need more info :)
The cover comes off this type of set pretty easy ,, it should be held on buy a few screws or zip clips (the ones u only turn half way and they are loose)
 

vettman74

New Member
Re: onan marquis wont start

Sorry it took so long to get back. The tank is 3/4 full. It's a gas coach(no separate tank).I haven't tried to take the cover off. Does the cover come off without removing the genny?Also how hard is it to get the genny where it's easy to work on?Probably a question everyone wishes was a reality(no room to work on).The switch outside works intermittently,sometimes it works fine then it doesn't do anything(the inside works okay though).
 
G

Guest

Guest
Re: onan marquis wont start

The cover comes off pretty easy ,, u just gotta look for the screws ,, also i would look into a new switch for the outside ,, the switches are wired in paralell so if the coach switch works ok then the main switch may not ,,, onan used the switch at the set as the master switch ,, which i think may be ur problem,, i would try to replace the switch outside first and post back on the results ,, either way the sw has to be replaced,,, i would get an oem from Cummins,, it's not that much more ,,, JMHO :)
Bty do u have a manual for this set???
If so ,, u can see how the switches are wired ,, if not i know cummins web sight can direct u to the proper manual online ,,, also i would email the service about this prob,,,, :)
 

vettman74

New Member
Re: onan marquis wont start

Thanks. I have a manual ordered,should be here in the next couple of days. I'll call Cummins and see about a switch while I'm waiting.
Thanks.
Any other suggestions are welcomed also,while I have to wait on the manual,and probably the switch,doesn't hurt to do more diagnostics.
 

vettman74

New Member
RE: onan marquis wont start

Okay got the new start switch,had to soldered in and reinstalled,nothing.I still have a fire problem.I have a good 12 volt at the solenoid. I checked the crank trigger like it said and had a flashing light(12 volt tester).But when I pull a plug and grounded it to the block,no spark? Is there anything it could be other than the coil?

Help!!


Thanks Mark
 
G

Guest

Guest
RE: onan marquis wont start

what year is it,, the gen set??
i have seen this a couple of times but it ended up being the points,, but that was with older sets ,, u may need some plug wires ,, did u pull off the other wire for the second cylinder and ck it ??? does it have spark???
 

vettman74

New Member
RE: onan marquis wont start

I have it narrowed down to a fuel problem.If I remove the fuel line gas comes out under prssure(slight).But it won't start.I give it a shot of starting fluid and it fires up and soon dies. Anyone have any testing that could be helpful?There is a relay attached to the air cleaner assembly?
 
G

Guest

Guest
RE: onan marquis wont start

Are u sure that there is not a fuel pump mounted somewhere near or on the gentset???
If not i would ck the fuel line from the tank to the set ,,, sometimes they get cracks and tend to suck air ,, if it's a gravity fed set ,,, i would take compressed air and blow thru the hose ,, u may have a collasped hose or a stopped up intake on the main fuel tank....
Post us back on the results :)
 
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