ive narrowed the no start problem down to the fuel tank.....i have put 25 gallon of fuel in the 100 gallon tank....i cant get no fuel to come out of the line to the generator,,,,,i blow on the line and i can here it bubble in the tank,,,,but that hasnt changed since i put the fuel in....does it take more fuel for the generator top pick it up or maybe something in the tank wrong....anyone know how the pickup is made or if it could go bad or break off inside the tank...any help would be greatly appreciated

Yes there is a level at which the generator pickup starts sucking air. That's to keep you from stranding yourself when the generator sucks the fuel tank dry.If you're brave try sucking instead of blowing on the line. Start with a really slow light suck. You will know right away, either you are sucking liquid or you are sucking air. Just be ready to get your mouth out of the way.Or go fill up the tank and see if you get better results.Yes my mind goes there too, but keep it clean.

The Genset 1/4 fill pick up tube is not set in exacts. It is just a tube down from the top of the tank. So, in this case, I would get another 25 gallons in the tank and retest.

You said than no fuel is getting to the generator. Did you verify this by disconnecting the fuel line to the carburetor and turning over engine and seeing if any fuel squirts out? If nothing comes out, I would insert the fuel pick up line into a gal of gas and do the same thing. If no fuel comes out check the fuel pump. This of course assumes your fuel level is high enough to reach the pickup tube. Gas in your mouth will tell you that as someone has already suggested.

Another check would be to stick a length of hose on the fuel pump inlet and stick the other end in a can of gas. If the generator starts and runs ok, then the fuel may be too low in the tank or there may be a crack in the fuel line that's letting air in.

ok now i have fuel.....put 50 gallon in it total and it picked it up......now the problem is generator want run unless u choke it after it fires to keep it running you have to move choke lever open and shut to keep it running.....when u let go of the choke it dies....want start back until u choke it....maybe something inside the carb....one other ? what kind of fuel pressure is this thing suppose to have...any help be appreciated...thanks

onan marquis 7000 generator /no start | Good Sam Community

Gary45
Explorer
May 11, 2022
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwix2-f-vtj3AhUjAp0JHedMBGwQFnoECDQQAw&url=https%3A%2F%2Fwww.thorforums.com%2Fforums%2Ff8%2Fwhy-cummins-onan-does-not-recommend-synthetic-oil-23430.html&usg=AOvVaw2CtbD3ncBwae5MIazeZiCG

Link to Cummins Onan re oil
Gary45
Explorer
May 11, 2022
Richard, when I used to have air-cooled motorcycles I could come to stop on the highway and put my hand on the fins, the only time they ever got very hot was idling in traffic, no cooling fan

The water cooled bikes now get extremely hot all the time.
RLS7201
Explorer II
May 10, 2022
Gary45 wrote:
RLS7201 wrote:
Air cooled engines run hotter than water cooled engines. Thus the manufacture does not recommend multi viscosity oils. BUT! that ruling was for non-synthetic oil. Standard oils loose their multi viscosity capacity when run to hot and thin out. So when running multi viscosity oils in air cooled engines, always use synthetic oil. I have the same generator as you and have used 10W-30 synthetic for 22 years with no problems.

Richard

Regular multi viscosity oil is fine in an air cooled motor, air cooled motors do not have a thermostat to make them run as hot as water cooled motors. There are no air cooled car or motorcycle engines anymore because they cannot get them to run hot enough for modern fuel injection pollution control systems.

Onan strongly resists multi viscosity oils in the 7K NHM air cooled generator.
Obviously you have no understanding of the additives that make 10 weight oil multi viscosity. Those additives break down in small air cooled engines and leave you with 10 weight oil.
The reason for water cooled motorcycle engines, is because the higher compression engines don't cool well enough with air. You have it backwards.

Richard

Richard
joebedford
Nomad II
May 10, 2022
Gary45 wrote:
There are no air cooled car or motorcycle engines anymore because they cannot get them to run hot enough for modern fuel injection pollution control systems.
Uhhhh, Harley? Some are liquid cooled but most are not.
Gary45
Explorer
May 10, 2022
RLS7201 wrote:
Air cooled engines run hotter than water cooled engines. Thus the manufacture does not recommend multi viscosity oils. BUT! that ruling was for non-synthetic oil. Standard oils loose their multi viscosity capacity when run to hot and thin out. So when running multi viscosity oils in air cooled engines, always use synthetic oil. I have the same generator as you and have used 10W-30 synthetic for 22 years with no problems.

Richard

Regular multi viscosity oil is fine in an air cooled motor, air cooled motors do not have a thermostat to make them run as hot as water cooled motors. There are no air cooled car or motorcycle engines anymore because they cannot get them to run hot enough for modern fuel injection pollution control systems.
RLS7201
Explorer II
May 10, 2022
Air cooled engines run hotter than water cooled engines. Thus the manufacture does not recommend multi viscosity oils. BUT! that ruling was for non-synthetic oil. Standard oils loose their multi viscosity capacity when run to hot and thin out. So when running multi viscosity oils in air cooled engines, always use synthetic oil. I have the same generator as you and have used 10W-30 synthetic for 22 years with no problems.

Richard
Kpackpackkelley
Explorer II
May 10, 2022
Gary45 wrote:
15 - 40 any brand

Good info.
Gary45
Explorer
May 10, 2022
15 - 40 any brand
Stickkman99
Explorer
May 09, 2022
ok....got the generator running........main jet was clogged.....everything running good.....now to change the oil and filter...i dont have a manual....so what oil should i use??
Gary45
Explorer
May 08, 2022
Main jet is plugged, it screws into the bottom of the fuel bowl, usually just unscrew clean and replace.

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