My Generac Wheelhouse 5500 / 5550 generator (made by Briggs and Stratton) was sitting in my shed for years without seeing much action. I knew I had to test it every month but without any need, it was sort of forgotten and unused. So when it refused to start with Hurricane Sandy bearing down us, all I managed to do was flood the engine when I repeatedly pulled the starter rope.
Although I was fortunate enough to purchase a new Briggs and Stratton 5500 Storm Responder generator from Home Depot at 3 AM, I shudder at the thought of not having electricity with 2 young children (by the way, my electricity was out for 14 straight days).
While my new generator was up and running, I was able to get my Generac generator to up and running, thanks to Internet and some fine folks at DIYChatroom (thanks again guys!).
I wrote this article to capture what I learned in hoping that it might help someone else to get their generators up and running.
There are 2 main problems you may face with a generator that has been sitting around:
- Generator runs fine but there is no electrical output
- Generator runs poorly or does not start at all
- Engine starts but quits after running for about 10-15 seconds;
- Engine does not start but gas leaks from the air filter
- Engine will only start for few seconds with a squirt of starter fluid
- Engine will run rough under full choke but dies when choke is opened
- Engine sputters, guzzles gas then dies
If there is no electricity, you may need to field flash your generator or troubleshoot the automatic voltage regulator (AVR). Please see my other post titled “Troubleshooting a Portable Generator with no Voltage Power Output” (LINK -TBD)
Briggs and Stratton engine found in Generac Wheelhouse 5500 / 5550 generator came with either a Walbro or Nikki carburetors.
Information in this post pertains to only Nikki because my particular Generac Wheelhouse generator came with it (B&S OEM part # 697978 G02523 4312 A).
Generator’s inability to start of remain running has lots to do with old, stale gasoline. Most research I’ve read indicates that the gasoline goes stale after only 30 days after it is manufactured. After 30 days t starts to form varnish that looks like red rust flakes.
Varnish tends to stick and clog internal components like a needle valve, emulsion tube, etc. where tiny holes are critical for the engine to properly work properly.
REPLACE OR OVERHAUL THE CARBURETOR?
BUY A NEW BRIGGS AND STRATTON CARBURETOR – PART # 591378
If you don’t have the time for an overhaul / rebuild (i.e. a storm is coming!), you will want to buy a replacement Briggs & Stratton Carburetor – Part # 591378.
Installing a replacement carburetor is basically a drop-in that takes less than 20 minutes. If you do buy one, you need re-use the choke handle bar because the new one is shorter than the original one (this involves simply removing a choke plate).
Nikkie Carb Part #697879 has been discontinued and official replacement part is not available. Although the packaging on the new carburetor #591378 does not state that it can replace #697978, it works.
REPAIRING OR OVERHAULING THE OLD CARBURETOR
Overhauling a carburetor is more labor intensive process and may not be a good solution if you need to get the generator up and running and you need to do other things to get ready.
I am going to share my detailed step-by-step instructions with you so that if you have some spare time,
I think you can agree with me that spending 100 bucks for a new Briggs & Stratton Carburetor Part # 591378 is far cheaper than buying a new generator
I had three choices in trying to solve my problem:
- VARNISH REMOVAL – Costs may be $10 or under; least expensive route but may develop leaks if old gasket is damaged during cleaning process
- OVERHAUL – Costs about $25 for an overhaul / rebuild kit
- REPLACE – Costs about $100
I ultimately chose to go with option #2 because I felt confident that my generator will be working after the engine tuneup (replacing air filter, spark plug, oil change, etc.) + overhauling my carburetor.
- Mini socket set – Nothing fancy. Any 1/4 inch with few metric and standard sockets will do (like this GearWrench 85035 35 Pc MicroDriver Set)
- Drive Extension Bar – This makes it easier to turn your mini ratchet in awkward spaces. I recommend this (Neiko Pro-Grade 9-Piece ‘Wobble’ Angle Extension Bar Set – 1/4, 3/8 & 1/2-Inch) because in addition to extension bars, the set also includes 3 adapters to use on larger socket ratchets.
- External Torx Bit (E5) – Instead of usual male torx bit, this socket accepts a torx bit (i.e. female); If you don’t have it, it may be more cost efficient to purchase like Neiko 35 piece Torx Bit and External Torx Socket Set. You can read my review of it here.
- Gloves – Nitrile / Latex / Vinyl
- Drop cloth and/or plastic sheet
- Adjustable pliers (if you don’t have one, read my Must-Have-Tool for your DIY Toolbox – Adjustable Pliers review article)
- Plastic bowel + paper towel
- Thin wire – thickness should resemble a “repair tag” or “for sale tag” wires. I used a wire tie and stripped off the plastic outer sheathing
- Spark Plug Gap Tool – Lisle 67870 Spark Plug Gauge Gap Tool
- TRDP15 Heavy Duty High Speed Siphon Liquid Transfer Pump with Bendable Suction Tube System
- Carb Overhaul / Rebuild Kit:
- Briggs & Stratton 696146 Carburetor Overhaul Kit
- I’d suggest purchasing this part before taking the carburetor apart
- Spark Plug:
- Champion Spark Plug RC12YC; or
- Autolite 3924 Copper Core Spark Plug;
- Use a spark plug gap tool to set the spacing to 0.030 inches
- Air Filter – Briggs & Stratton 491588S Flat Air Filter Cartridge
- Carb Cleaner – Briggs & Stratton 100042 Choke / Carburetor Cleaner- 16-Ounce or Gum Out
- Enginer Cleaner (internal) – Sea Foam Motor Tune Up– similar to Gum Out but works inside the engine
My next post will cover engine tuneup and Nikki carburetor overhaul (UPDATE: Fast and Easy Fix for Your Generac Wheelhouse 5500 / 5550 Portable Generator (Part 2)
Please don’t forget to check the reference links as this section contains links to lots of useful information that are not easily found on the internet.
In the meantime, if you found this article to be useful, can you do me a favor and sign up for my newsletter? The signup form is found at the top of the screen on the right side.
Thanks and wish me luck!
- Briggs and Stratton – What would prevent an engine from starting
- Briggs and Stratton – Operator’s Manual
- Briggs and Stratton – Parts List Rev. 3
- Generac Wheelhouse 5500 / 5550 – Parts List (PLEASE NOTE: This is for Rev 5)
- Supplemental Generator Data for 87971 Rev. 7
- Outdoorpowerinfo.com – Disassembly, Cleaning and Repair of Briggs and Stratton Intek Single Cylinder OHV Nikki Carb
- Briggs and Stratton – Illustrated Part’s List
- Youtube – Briggs and Stratton 10hp Generator Carburetor Repair Video
- Briggs and Stratton – Care and Repair Manual (abbreviated, online PDF version; not too useful
- Briggs and Stratton – Familiarization and Troubleshooting Guide
- Briggs and Stratton – Carburetion Troubleshooting Quick Reference Guide (PDF)