I've got 2 of these from a GL auction and can not get the parts to fully assemble them... My only bum GL purchase to date... Lucky you, they are good gensets but have to be handled with kiddie gloves!!
If it cranked at first it's got to be something simple...
I would start with the fuel filters and separator, pick up a set and a new set of gaskets for
ALL of them, it only takes a small air leak to get a poof of smoke but no start/run situation going. It is possible to get fuel FLOW but not pressure on these. I have seen people goof up and double up the canister gaskets which seals fuel from coming out but lets air in. That will make you crazy trying to figure it out. I HAD the numbers for the filters and gaskets but can not figure out where I put them... If you pull the filters and gaskets, take them to Napa and get them crossed.
After you do all of that bleed it again by first disconnecting the "in" line to the IP pump and allow the fuel pumps to push fuel up to the IP... Then disconnect the return line at the IP pump (small lines that run from the back of the injector body's into a tee block, and back to the IP) Spin the engine over until the air bleeds, tighten the line up and then try cranking it.
If you are SURE that you have a sealed fuel system and you think your preheat is out and may be causing the problem (doubtful).... I HATE recommending this but give it a hit of ether.
If all else fails and you think you have a IP problem which is possible (trash/storage) I would recommend taking it to a shop.. I say this because the IP's are HARD to come by and priced like gold. The pumps have not been produced sense 90-92' and the military has a recycle program for rebuild with the manufacture which is why it is so rare to find a surplus MEP with a intact IP pump. Remans can be found for 450 but its difficult, most people ask 900-1200$, Onan thinks their worth 2200$... Funny people they are!!! (oil coolers, fan shrouds, igniters and voltage regulators are high maintenance items and also no longer produced which is why they too are often times stripped).
The glow plugs PN 330-0106 are a piss poor... The civilian 24V cross is a Champion number CH42, 14-18$ Napa can special order these but you MAY have to buy a whole box of 10 to get them. These things can be VERY difficult to remove from the head and love to snap off in the process. I recommend getting the motor running before messing with these, give it about 30 mins of run time, shut it down and then pull the glow plugs while hot, they usually come out easier and se a LIBERAL amount of high temp anti-seize when installing the new ones.
I don't think you would need the intake heaters in Iowa but the number printed on them is good for crossing also... I think they run about 48$ each.
If you want to convert your oil filter to a spin on Onan PN 122-0245 is the adapter plate needed.
Hope some of this helps... If not try here, most people have the cilivian versons of these but there are a few MEP owners around.
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