Generator hard start

[Nadge]

I have a 2016 Newmar Ventana DP with an 8K Onan Gen.
It has 298 run hrs.
I change the oil and fuel filter once a year.
The last two attempts to start took almost 45 seconds to start. Temp 42F.
Typically only takes ~ 15 seconds after priming for 15 seconds each startup.
Starer cranks normally/quickly.
What is the longest cranking time I should not exceed?

I try to stay ahead of changes to the normal.
Anyone recognize these symptoms?
How do I rectify?

[iluvuk]

Originally Posted by Nadge

I have a 2016 Newmar Ventana DP with an 8K Onan Gen.
It has 298 run hrs.
I change the oil and fuel filter once a year.
The last two attempts to start took almost 45 seconds to start. Temp 42F.
Typically only takes ~ 15 seconds after priming for 15 seconds each startup.
Starer cranks normally/quickly.
What is the longest cranking time I should not exceed?

I try to stay ahead of changes to the normal.
Anyone recognize these symptoms?
How do I rectify?

Diesel generators will spend time warming up prior to kicking on the colder it is out there. Sometimes it takes almost 60 seconds before it kicks on when near freezing temps for me.

[Dutch Star Don]

In colder weather, hold the Start/Stop button down longer in the Stop position, then try starting.

[iluvuk]

On my 2018 Onan Diesel genset it says to hold the start button until it cranks and starts. The first 20 or 30 seconds it is just warming up and getting ready to crank (depending on how cold). Mine does not say to hold the stop button first so you might check your model. I did have a prior gas RV and those generators do prime with fuel by pushing the stop button, but not my diesel. Hope this helps.

[Tha_Rooster]

Originally Posted by Dutch Star Don

In colder weather, hold the Start/Stop button down longer in the Stop position, then try starting.

My diesel you hold start down it primes then starts.

[Granite17]

Originally Posted by Dutch Star Don

In colder weather, hold the Start/Stop button down longer in the Stop position, then try starting.

Gotta ask, what does holding in the stop position do?

[153stars]

From the remote buttons primes and preheat with glow plugs ,mimics prime at genny. My Generac may a little different from the many years of Onan .

[tomgrigsby]

Originally Posted by Granite17

Gotta ask, what does holding in the stop position do?

Same with my 7500, holding stop button allows an extended prime. Starts right up after that

[twinboat]

Holding the stop button runs the fuel pump on both gas and diesel engines.

A diesel shouldn't need be primed, if the fuel system is in good shape. You prime it after maintance involving the fuel system.

It may need preheat, that helps heat up the cold combustion chamber, so the fuel fires off.

On gas generators, holding the stop button just turns on the fuel pump, so it fills the carburator bowl.
That's needed if the generator has sat a few days or more and the gas has evaporated out of the bowl.
The choke is what assists with cold starting of carburated gas engines.

[jacwjames]

I wonder if you glow plug circuit is working. On mine there is a 25 amp fuse for the circuit. When starting there is a sensor that controls this based on temperature.

[Outbound]

If my batteries are a little low it takes longer to start, at 100% charge always quick starts.