I am getting close to finishing my genset install project. Found a not working 7kw onan genset, repaired the broken drive pulley and replaced belt.. converted to propane, runs great. have added the Transfer switch to the FW and wired to the front compartment. Had the metal enclosure built and have the floor cutout template.. now to actually put the genset into the front compartment.. but the thing weighs 300lbs. I can't find any specs on what the floor of the front compartment will hold. (keystone tech support didn't have any specs for the floor weight capacity)also, the floor is 3.5 inches lower than the door opening, so once you get it in there, I don't know how you would ever get it out. (the enclosure is big enough that you couldn't get it out first.so I've been looking at creating a drawer, or at least mounting the genset on risers to get the base even with the front door opening. this only makes the weight thing more of an issue, cause all 300lbs will be sitting on the base of the riser (in either case). lets do the weight math, risers are 3.5in square tube, 24 inches long, and need 2 of them. 300lbs/(24x3.5x2)that comes out to 1.75 psi. not muchthe floor seems to be some thickness sheet metal (haven't cut it yet), resting on the legs of angle iron, which are welded to the frame (I think)if I can get the riser to rest on the (1"?) angle iron lip too, then the pressure on those two would be 300lbs/(1x3.5x4) = 21 psi each end of both risers. (300/4/ 3.5sq in)I have some 3/16 x 7 x 36 strips of flat stock that I could use as reinforcement in the riser area. not enough for the whole floor section as 1 piece. here is a side view of the layout

What access do you need to change the oil and perform other routine maintenance on the generator? On mine (a completely different model), the oil drain is on the underside of the generator, with a little access panel attached to the outer cover. It wouldn't work well to have it installed over an unbroken floor. Likewise, there's the need for the exhaust plumbing to exit underneath. The generator appears to be mounted to an angle iron frame, which is bolted to the undercarriage of the motorhome, so far as I've been able to suss out.I guess I'm suggesting that you consider removing the floor of the compartment and see if you can't find a way to make it able to be raised/lowered from underneath, rather than slid in from the side/front. Of course, for routine maintenance and such you'd just leave it in place.Do be careful to seal the compartment thoroughly from the interior of the trailer, and maybe consider adding some fire/sound insulation.

I would start with a 3/4" plywood base in the floor of the compartment, that will distribute the weight of the riser mounts pretty evenly across the structure and eliminate any pressure points that could overstress the structure. You can add sheet metal on top of the plywood for fire protection and oil spills.If you want to stay with metal, then a pair of 2x2 square tubes that run the full width of the compartment should give you good weight distribution as well.I would also look at a pair of HD drawer slides (like these) that are rated in excess of 400 lbs per pair. Raise the gen up to the level of the compartment door and mount on full extension slides so you can easily roll the unit out for repair and maintenance.Plus, if you need to completely remove, you can support the genset from underneath while you disconnect the slide extensions.

I set it right on the floor- removing really won't be that big a deal. I ran 1 1/2" angle underneath the compartment- frame to frame, right at the mounting holes. Plywood as an outside lining for the sheet metal enclosure.The trailer I installed it in was "generator ready", but I didn't trust the sheet metal to hold it.The hardest part is locating the holes to cut in the floor.

Don't forget sound insulation. As per Onan spec, you should have insulation on all sides (perhaps the door) of the compartment, but not beneath the genset (so fuel dripping on it doesn't cause problems.) You should also have a vent in the front as well.It also can't hurt to rubber shock mount everything (exhaust pipes, fuel and electric lines), and use the Onan resonator. This will quiet things down remarkably.

I installed a Onan Marquis Gold 7000 in our front compartment. The fiver wasn't gen ready which I liked because I "do it my way". I'm like Chris, didn't trust the floor. And the way the Onan cools, it sucks air from the bottom so I just removed the floor and welded some 2" square tubing to the fiver frame. I also made it so it would slide out of the compartment since an Onan is like an old lady, you know, lots of TLC. One thing to remember, make sure the bottom of the genny is above the inside lip of the door frame. So if it has to come out, you don't have to lift and pull at the same time. I have an Alfa, and a friend of mine had an Alfa also with a factory installed genny. He had a problem with the Onan that was covered under warranty and took it to an Onan shop. His genny was below the lip of door and he said the Onan techs came up with new words he never heard!

anyone install Onan genset in front compartment?

tatest
Explorer II
Mar 27, 2015
Winnebago installed my genset (4KW) in the front compartment. That compartment does not have a floor. It doesn't really have walls, either, it is just and open area between wall and frame rails, well below the floor, where the generator is mounted on steel supports.

This makes for a relatively noisy installation, but the genset is well ventilated.
sdetweil
Explorer
Mar 27, 2015
Stefonius wrote:
I'd like to know what you did to convert your genset to LP. I have an Onan Marquis Gold 5500 gas, and I need to do the same conversion. Where did you get your kit? Is it OEM or aftermarket? Was it easy to install? I could pay Onan to do it when they install the unit, but I might save a ton of money doing it myself beforehand.

this is aftermarket. Onan has discontinued their conversion kits.

I ordered from uscarb.com
they have a unique adapter, which is a nozzle on a very thin plate that fits between the carb and the air cleaner. its dual fuel propane or natural gas for my system.
search 'motor snorkel us carburetion' on youtube.com for a number of videos that show the product and install..
the regulator is the same as the old onan kit.. so the difference is no carb change. just install the nozzle.

maybe 30 mins total install time.
just at $200 including shipping. 187+12 for me

starts and runs like a champ. no carb change, just plugged the gas line (removed the fuel pump so I can run the propane hose up thru the gas line opening.)

I installed an electric valve to shutoff the propane before the regulator they provide. the valve is wired to the fuel pump wiring on the onan. I'm going to add a T out of my auto switch regulator to plumb the genset.

oh, and my FW is not gen ready, so I am going to use the EC-30W wireless controller. it detects power loss, can be programmed for restricted hours, and also temperature to start the genset.
Stefonius
Explorer
Mar 27, 2015
I'd like to know what you did to convert your genset to LP. I have an Onan Marquis Gold 5500 gas, and I need to do the same conversion. Where did you get your kit? Is it OEM or aftermarket? Was it easy to install? I could pay Onan to do it when they install the unit, but I might save a ton of money doing it myself beforehand.
sdetweil
Explorer
Mar 26, 2015
Stefonius wrote:
sdetweil wrote:
Stefonius wrote:
Sdetweil - I have a PDF copy of the Onan Generator Accessory Catalog. They make two different mounting options for our gensets in a FW front compartment. The underfloor mounting kit attaches to the sides of the generator, and then bolts to the TOP of the FW's front compartment. The genset basically hangs in place. The other option is a slide out tray that goes into the floor of the compartment. In either case, you'll be cutting out a large rectangular section of the compartment floor. The generator gets combustion air, cooling air and exhausts from the bottom. I am having trouble finding an active link for this catalog, so I can't post a link, but I'll PM it to you if you'd like to see it.
thanks.. I think that catalog is here page 16 shows a slide out, but it is under floor again. pages 28 & 29 show more of the same.
or here pages 53 & 54.. that slide set on page 53 is $832!
It's your second link. The kits would be on page number 37 & 38 (41st and 42nd page in the document). Not sure what they cost, but I think the best option would be the underfloor mount. The material at the top of the compartment is quite a bit sturdier than the sheet metal floor.

ok, got it.. my enclosure is based on floor mount.. looks like this
(this is not mine, but mine is similar)
Stefonius
Explorer
Mar 26, 2015
sdetweil wrote:
Stefonius wrote:
Sdetweil - I have a PDF copy of the Onan Generator Accessory Catalog. They make two different mounting options for our gensets in a FW front compartment. The underfloor mounting kit attaches to the sides of the generator, and then bolts to the TOP of the FW's front compartment. The genset basically hangs in place. The other option is a slide out tray that goes into the floor of the compartment. In either case, you'll be cutting out a large rectangular section of the compartment floor. The generator gets combustion air, cooling air and exhausts from the bottom. I am having trouble finding an active link for this catalog, so I can't post a link, but I'll PM it to you if you'd like to see it.
thanks.. I think that catalog is here page 16 shows a slide out, but it is under floor again. pages 28 & 29 show more of the same.
or here pages 53 & 54.. that slide set on page 53 is $832!
It's your second link. The kits would be on page number 37 & 38 (41st and 42nd page in the document). Not sure what they cost, but I think the best option would be the underfloor mount. The material at the top of the compartment is quite a bit sturdier than the sheet metal floor.
sdetweil
Explorer
Mar 26, 2015
Stefonius wrote:
Sdetweil - I have a PDF copy of the Onan Generator Accessory Catalog. They make two different mounting options for our gensets in a FW front compartment. The underfloor mounting kit attaches to the sides of the generator, and then bolts to the TOP of the FW's front compartment. The genset basically hangs in place. The other option is a slide out tray that goes into the floor of the compartment. In either case, you'll be cutting out a large rectangular section of the compartment floor. The generator gets combustion air, cooling air and exhausts from the bottom. I am having trouble finding an active link for this catalog, so I can't post a link, but I'll PM it to you if you'd like to see it.

thanks.. I think that catalog is here page 16 shows a slide out, but it is under floor again. pages 28 & 29 show more of the same.
or here pages 53 & 54.. that slide set on page 53 is $832!
Stefonius
Explorer
Mar 26, 2015
Sdetweil - I have a PDF copy of the Onan Generator Accessory Catalog. They make two different mounting options for our gensets in a FW front compartment. The underfloor mounting kit attaches to the sides of the generator, and then bolts to the TOP of the FW's front compartment. The genset basically hangs in place. The other option is a slide out tray that goes into the floor of the compartment. In either case, you'll be cutting out a large rectangular section of the compartment floor. The generator gets combustion air, cooling air and exhausts from the bottom. I am having trouble finding an active link for this catalog, so I can't post a link, but I'll PM it to you if you'd like to see it.
sdetweil
Explorer
Mar 26, 2015
DrewE wrote:
What access do you need to change the oil and perform other routine maintenance on the generator? On mine (a completely different model), the oil drain is on the underside of the generator, with a little access panel attached to the outer cover. It wouldn't work well to have it installed over an unbroken floor. Likewise, there's the need for the exhaust plumbing to exit underneath. The generator appears to be mounted to an angle iron frame, which is bolted to the undercarriage of the motorhome, so far as I've been able to suss out.

I guess I'm suggesting that you consider removing the floor of the compartment and see if you can't find a way to make it able to be raised/lowered from underneath, rather than slid in from the side/front. Of course, for routine maintenance and such you'd just leave it in place.

Do be careful to seal the compartment thoroughly from the interior of the trailer, and maybe consider adding some fire/sound insulation.

The floor cutout template makes access for oil chg maintenance and air heat exhaust.
sdetweil
Explorer
Mar 26, 2015
Chris Bryant wrote:
I set it right on the floor- removing really won't be that big a deal. I ran 1 1/2" angle underneath the compartment- frame to frame, right at the mounting holes. Plywood as an outside lining for the sheet metal enclosure.
The trailer I installed it in was "generator ready", but I didn't trust the sheet metal to hold it.
The hardest part is locating the holes to cut in the floor.

I have the floor cutout template, transferred to some poster board, so it's just mark and use my plasma cutter.
sdetweil
Explorer
Mar 26, 2015
bobsallyh wrote:
I installed a Onan Marquis Gold 7000 in our front compartment. The fiver wasn't gen ready which I liked because I "do it my way". I'm like Chris, didn't trust the floor. And the way the Onan cools, it sucks air from the bottom so I just removed the floor and welded some 2" square tubing to the fiver frame. I also made it so it would slide out of the compartment since an Onan is like an old lady, you know, lots of TLC. One thing to remember, make sure the bottom of the genny is above the inside lip of the door frame. So if it has to come out, you don't have to lift and pull at the same time. I have an Alfa, and a friend of mine had an Alfa also with a factory installed genny. He had a problem with the Onan that was covered under warranty and took it to an Onan shop. His genny was below the lip of door and he said the Onan techs came up with new words he never heard!

Thanks. Hadn't thought of just cutting out the floor vs just the cutouts.

Definitely not gonna let it down without some easy way to get it back up and out.

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