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Topic: Onan generator removal from Oshkosh chassis to replace the insulation (Read 929 times) previous topic - next topic

Onan generator removal from Oshkosh chassis to replace the insulation

I have searched the posts and found no mention of anyone removing a Onan propane generator from an Oshkosh chassis.  It is obvious that I first need to remove the door and then disconnect the propane line and twelve volt wire from the starter (after shutting off the propane at the tank) and then disconnect the exhaust pipe.  I can find only three bolts that appear to be holding in the generator, see the attached pictures.  One bolt screws in from the side behind the front wheel the other two are at opposite ends of the generator.  It looks like I can get to the one bolt over the muffler but I cannot see anyway to access the top of the other bolt.  The oily stains you see are from the Kroil I used since the bolts are really rusty.  Once loose I have a hydraulic lift cart I bought from Harbor Freight that should go high enough to support the generator.

From some other posts I know I should shut off the propane and then run the generator to drain the line but that is not possible as the generator refuses to run once the start switch is released - I will tackle that in another post.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #1 –
I would think that if you turned the propane off, then lit the stove most of the propane in the lines would be burned off. What little there would be left would not pose a problem

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #2 –
Mine looks just like that but I don't want to tackle it.  I am thinking about having Cummins / Onan pull it while I take the coach and reinsulate the compartment and add a joey slide then have them reinstall it so that I can pull it out to easily get at that rear plug during tune-ups.  Probably should look for someone other than Cummins to save a little money.  If I wait long enough someone will come out with a diesel generator that will fit in this space.  They are getting smaller all the time.
Dwayne Keith
1992 U240
3116/MD3060

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #3 –
You may find that the additional height of the sliding tray for the base of the generator will prevent the generator for fitting into the compartment.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #4 –
Quote from: El_Dorado –
I would think that if you turned the propane off, then lit the stove most of the propane in the lines would be burned off. What little there would be left would not pose a problem

Perhaps.  If a VAPOR LP generator, I agree. 

But, if a LIQUID LP generator, NO, you have a LOT of propane in the line to the generator. 

How do you tell which you have?  Look at the propane tank.  If everything (house and generator) run off the VAPOR tap and nothing runs off the LIQUID tap, you have a vapor generator and are good to go.

If, however you have a line going from the LIQUID tap on the LP tank, you have a LIQUID LP generator.  Correct procedure is to start the generator.  Then turn off the Liquid LP port.  Let the generator run out of fuel.  NOW you are good to go/little propane will leak out.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #5 –
The bolt in your second picture is a stop to keep the generator from coming all the way out so you can access the back head to be able to tune uup and do a decarbon job.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #6 –
Quote from: wolfe10 –
Perhaps.  If a VAPOR LP generator, I agree. 

But, if a LIQUID LP generator, NO, you have a LOT of propane in the line to the generator. 

How do you tell which you have?  Look at the propane tank.  If everything (house and generator) run off the VAPOR tap and nothing runs off the LIQUID tap, you have a vapor generator and are good to go.

If, however you have a line going from the LIQUID tap on the LP tank, you have a LIQUID LP generator.  Correct procedure is to start the generator.  Then turn off the Liquid LP port.  Let the generator run out of fuel.  NOW you are good to go/little propane will leak out.



Thanks for teaching me about that!
 

Re: Onan generator removal from Oshkosh chassis to replace the insulation

Reply #7 –
Yesterday I bit the bullet and removed the generator.  I made one unnecessary move not realizing that the sides of the gen housing were attached to the chassis - I separated the remote switch wiring harness from the power lead which was taped to it.  Aw, heck, it needed to be redone anyway.  I will post a separate topic with a detailed description of the removal process with photos.  The process was simple and straight forward except that someone over tightened the u-bolt clamp for the exhaust pipe and made it impossible to remove without cutting it off.  Where can I get a replacement?  BTW, the generator is vapor fed as I discovered when I went to shut off the propane, all lines came from the vapor port.

I had never really looked at the gen compartment until I removed the gen.  I discovered that there was no insulation on the roof of the compartment.  Anyone know why?  Also, any suggestions on what to replace the old stuff with?  One of the things I am considering is using Dynamat with Dynapad but I have not yet checked the cost.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP