Filling Oil on Onan 5500

scottyb

Well-known member
I change my oil today for the 2nd time at 170 hours. Both times I have had trouble filling it back with oil. The manual says 2 qt but I can't seem to get two full qts in it. I fill it very slowly so that it doesn't overflow. I have to pour a little, then wait, then pour a little more. Finally after about 1-3/4 qts, that it. BTW, the engine was hot and I let all the oil drain out. I pre-filled the filter until it will not hold any more too. I started it a couple times and it's full. Is this common or am I missing something?
 

MTPockets

Well-known member
I noticed the same thing. No way two Qts will fit in mine either. The last cup or so I had to nurse a thimble full at a time. ......... Maybe a thinner oil would all fit... LOL.
 

porthole

Retired
2 quarts with filter?

Oil capacity is usually listed with a filter unless specifically excluding the filter.

Kind of like adding fuel to the Cyclone tank from a 5 gallon jug.
 

scottyb

Well-known member
2 quarts with filter?

Oil capacity is usually listed with a filter unless specifically excluding the filter.

Kind of like adding fuel to the Cyclone tank from a 5 gallon jug.

I believe it says that but I may be confusing it with my Exmark or my Mule, which I also changed their oil yesterday. I used part of the 2 qts to pre-fill the filter. I continued to top it off until it was saturated and would not take any more. It was brimming full when i put it on. Still only got about 1.75 qts added.
 

porthole

Retired
I believe it says that but I may be confusing it with my Exmark or my Mule, which I also changed their oil yesterday. I used part of the 2 qts to pre-fill the filter. I continued to top it off until it was saturated and would not take any more. It was brimming full when i put it on. Still only got about 1.75 qts added.

I remember it is a bit of chore getting the oil in, but don't remember the quantity. I will make note of it in the fall though.
Did you see my post about the fuel control solenoid?
 

whp4262

Well-known member
I change my oil today for the 2nd time at 170 hours. Both times I have had trouble filling it back with oil. The manual says 2 qt but I can't seem to get two full qts in it. I fill it very slowly so that it doesn't overflow. I have to pour a little, then wait, then pour a little more. Finally after about 1-3/4 qts, that it. BTW, the engine was hot and I let all the oil drain out. I pre-filled the filter until it will not hold any more too. I started it a couple times and it's full. Is this common or am I missing something?

Are you missing something? I would say you are missing about 1/4 quart of tank space, just my guess.:D
 

porthole

Retired
Yeah. So if it starts sputtering, give the solenoid a good rap. ;) No fuel pump recall?


Light rap :)

There is talk of a recall but no documentation. Neither dealer in Dover knew of any.
When I am back on my regular schedule I will be stopping at the dealer up where near I work, they seem to be a bit busier with the RV industry.

I do plan on getting a replacement fuel pump, that seems tp be a troublesome item as well. Probably go with an Airtex as it is about 1/4 the price of the Onan part.
 
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whp4262

Well-known member
I had fuel pump problems with the Onan Gen in my class A. I finally relocated the pump at the fuel source and pushed fuel to the Gen instead of pulling it, didn't have anymore fuel pump problems after that. Everything I have read and the pump manufacturers that I have talked to said the pumps are made to push fuel not suck fuel over long distances. Always been a little surprised that the pumps work as welll as they do in the Toy Haulers considering where the tank is in relation to the pump.
 
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