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Engine Tuneup for Generac Wheelhouse 5500 / 5550 Portable Generator


I don’t use my portable generator that often, other than maybe testing it once every month or two, so in my opinion it is critical to perform an engine tuneup at least every 12 months.

Read me
If you found this article via search engine, you may want to read:
** Fast and Easy Fix for Your Generac Wheelhouse 5500 / 5550 Portable Generator (Part 1)
** Fast and Easy Fix for Your Generac Wheelhouse 5500 / 5550 Portable Generator (Part 2)


Thankfully, no special tools are required. I do, however, recommend a siphon to drain the gas:



  1. Disconnect the spark plug cable;
  2. Remove old gas using a liquid siphon; I don’t recommend tipping your generator to empty out the gas because it can get messy and I do not want my electronics to soaked with gasoline;
  3. Drain the used oil by tipping the engine at about 30 degrees;
  4. Replenish with new engine oil;
  5. Replace the air filter;
  1. Remove the old spark with a new Champion spark plug with gap set to 0.030;
  2. Add fresh fuel (preferably premium or 93 octane gasoline);
  3. Add Sta-Bil to new fuel and let is sit for 30 min;


Using synthetic oil is probably an overkill, but it allows me to use the same engine oil throughout the entire year (and it is supposed to make the engine last longer) so it’s a worthy investment for me.

Thanks for reading and good luck with your tune up!


John O

Tuesday 11th of June 2024

There is some good advice in here Kevin but ... At no point, even after a poster asked, do you make mention of the engine other than "Briggs & Stratton". It seems that the majority of problems are with the engine due to age or improper care and you make some great suggestions for care a link or mention of the engine size/specs would be great and probably stop me from asking the easy questions like "what's the plug gap?". Thanks!


Thursday 13th of June 2024

Hi John,

Can you tell me what you are looking to do? This post was originally written back in 2009 and updated on 2015 so information is quite dated. Back then, Generac (generator) and Briggs (engine) did not publish detailed information so I had to piece them together.

Please note that I have three posts regarding the Generac Wheelhouse 5550 generator:

**Fast and Easy Fix for Your Generac Wheelhouse 5500 / 5550 Portable Generator (part 1) **Fast and Easy Fix for Your Generac Wheelhouse 5500 / 5550 Portable Generator (part 2) **Engine Tuneup for Generac Wheelhouse 5500 / 5550 Portable Generator

By the way, the spark plug gap is the distance between the center electrode and the ground electrode of a spark plug. This gap is crucial for proper engine performance as it influences the spark plug's ability to ignite the air-fuel mixture in the combustion chamber.

Let me know!


Tuesday 5th of September 2023

need the two (2) bolts that hold the carburetor on, there can I get them?


Tuesday 5th of September 2023

here you go...

Dave in Southwest PA

Wednesday 5th of April 2023

I have the Briggs & Stratton WheelHouse 5550. Put Ethanol-free gas in at the beginning of the pandemic and did not need to use it until this past weekend wind storm knocked power out for 15 hours. Took three pulls and fired right up. I ran it intermittently to pump the well (water), cistern (water) and our septic pump mainly....then would turn the refrigerator and freezers on for an hour or so throughout the down time. I bought this generator in 2005 and still going strong!

Dan Castle

Monday 22nd of February 2021

Thanks Kevin. Just trying to do the first real maintenance on it that I know of. I purchased it used 6 years ago and the only thing I have ever done is put a little fuel in it once per year, start it until it runs out of gas, and then put it away. Now I just used it for several days and nights in a row during the TX power outage. I want to make sure it runs well the next time I need it and I noticed I was having to run it on half choke. I am replacing the air filter which appears to be much of the problem. Also replacing the spark plug now. My big problem is I cannot get the carburetor bowl off because one of the screws is rusted on. I want to clean it out. I also can't get the idle screw to turn without almost stripping out the head.


Monday 22nd of February 2021

I found the owners manual for the generator but not for the engine. Do you have a link for it? Also, how many quarts of oil does it require?


Monday 22nd of February 2021

Hey Dan-

Unfortunately I was never able to locate the engine manual.....engine takes slightly more than 1 quart so after draining and capping the plug, add oil about 3/4 quarts then check the dipstick before adding more.

Did you have a specific problem with your engine?