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We have an onan 4000 light in our 2005 itasca motorhome, ot…

Customer Question
We have an onan...

We have an onan 4000 light in our 2005 itasca motorhome, ot runs great unless we are in a heat situation and it will not run, heat as in 90 or better

Mechanic's Assistant: I'll do all I can to help. How long have you been dealing with this?

Since we bought the motorhome, two years ago

Mechanic's Assistant: Do you plan on doing the work yourself?

If it is possible if not we need to find a dealer, btw the generator has approx 500 hours on it

Mechanic's Assistant: What's the make and model of the generator? And can you guesstimate how old it is?

Onan 4000 light single cylinder 2005, it is original on this 2005 itasca motorhome

Mechanic's Assistant: Anything else we should know to help you best?

No, it just wont carry a load when it is hot outside, it runs perfect with a load when temp is cool

Submitted: 7 months ago.Category: Small Engine
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Answered in 19 minutes by:
1/14/2018
Technician: Wayne, Engine Rebuilder replied 7 months ago
Wayne
Wayne, Engine Rebuilder
Category: Small Engine
Satisfied Customers: 11,341
Experience: many years on egine rebuilding, lawn mower,roto tiller,Truck,and small engines
Verified

Hi I’m Wayne

I will be assisting you with this issue today

is it air cooled engine or liquid cooled ??

is the compartment it is invented well??

Wayne

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Customer reply replied 7 months ago
Air cooled, the compartment is vented but also accessible from outside so we open the door so it has plenty of ventilation
Technician: Wayne, Engine Rebuilder replied 7 months ago

Hi Thank you for the response

does it quit running when the door is open

or continue to run

Wayne

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Customer reply replied 7 months ago
either way open or closed it stops, will run well for approx 5 min or less then stops, spark plugs and air cleaner have been changed
Technician: Wayne, Engine Rebuilder replied 7 months ago

Thank you for that

normally what causes that is fins blocked on

engine and head, wash with a dish soap and garden hose

if it continues to do it then there is a timing issue

the shear key on the flywheel will need to be checked

I hope this helps you

Wayne

My goal is to give you the best experience possible! I hope I have earned a 5-star rating! Please remember to rate my service by selecting the 5 stars at the top of the screen before you leave today. If you need more assistance, please use the reply box and let me know.

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Technician: Wayne, Engine Rebuilder replied 7 months ago

HI

Just following up with you

Did my answer help you ??

Wayne

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Customer reply replied 7 months ago
Will try your response to our problem when the weather breaks so it is possible to test.
Technician: Wayne, Engine Rebuilder replied 7 months ago

OK

My goal is to give you the best experience possible! I hope I have earned a 5-star rating! Please remember to rate my service by selecting the 5 stars at the top of the screen before you leave today. If you need more assistance, please use the reply box and let me know.

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Technician: Hank F., Technician replied 7 months ago
Hank F.
Hank F., Technician
Category: Small Engine
Satisfied Customers: 16,006
Experience: Certified on Onan and Generac generators
Verified

Sir, my name is ***** ***** I am a certified generator technician.

You were given some really bad advice in a previous post. You should NEVER use water on a generator. Water can seep into the windings of a generator, and it can take months to dry it out. Water is also very bad on the electronics.

You wouldn't spray water inside your TV or stereo, would you?

The only way to clean the engine of a genset is with a stiff bristle brush and compressed air.

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