onan marquis 7000 generator /no start

[Stickkman99]

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

[Gary45]

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]

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]

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]

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]

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]

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]

Gary45 wrote:
15 - 40 any brand

Good info.

[Gary45]

15 - 40 any brand

[Stickkman99]

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]

Main jet is plugged, it screws into the bottom of the fuel bowl, usually just unscrew clean and replace.

[Gjac]

I don't know what kind of choke you have but mine is a Bi-metal spring that opens up once the engine warms up. What kind of a choke do you have? Try adjusting or resetting the choke to where it starts. From your description it only starts when the choke is closed or on. From there it should open as the engine warms up. How old is your genset?

[Stickkman99]

i think the pump it is bad although it runs just no pressure.....maybe the carb is stopped up also since it would not run with the inline pump...??

[Stickkman99]

the pump for the generator only dribbeled.......the inline pump i put on it flowed good but it still would not start unless i kept the choke closed....

[Gjac]

Stickkman99 wrote:
the fuel is just a dribble......i did bypass the pump and put a inline electric pump on it straight to the carb......did the same thing....

Are you saying the inline pump produced just a dribble also?