My Tractor Forum banner
  • Are you passionate about Tractors? Would you like to write about topics that interest you and get paid for it? Read all about it here!
1 - 7 of 7 Posts

·
Registered
Joined
·
504 Posts
Discussion Starter · #1 ·
The majority of wearing parts on a Lawn Boy D-400 engine are the external parts that make up the governor, governor linkage, throttle shaft and carburetor primer assembly. Most engine troubles can be traced to these parts. Over the years I’ve made more reliable and longer lasting versions of most these parts and posted the information.
This latest retrofit part is a bronze governor collar that has been in use for several seasons now. The die cast original can develop a wear groove on the top where the flyweight arms make contact. As this groove wears deeper it takes some of the tension off the governor spring causing the engine speed to drop below 3200 rpm. This new collar is machined from 954 bearing bronze. It is slightly heavier than the original (3.5 grams) but that has not affected the governor operation. The bronze has the bearing quality needed for this particular part but more important is its hardness compared to the original. One of these new collars was installed on a model 7024 in April of 2016.The photo shows this collar and the flyweights as removed after 318.1 total hours of actual running time on the hour meter. There is no wear groove on the top of the collar and only slight wear on the flyweight arms.
Product Rim Bicycle part Household hardware Gas
Plant Sky Motor vehicle Cloud Tree
 

·
Super Moderator and over 6K Posts!
Joined
·
6,405 Posts
Now that is some good innovation Mike. I would guess the cast collar was plenty good and cheap for Lawnboy but that bronze retrofit would certainly extend the governor life. For most of us we just replace them or if they are not too bad we file and sand the top to remove the groove. Just had to replace one on the 5273. Are you thinking of producing these and selling them? Guys would probably only have to buy one per mower and they would last a very long time. Bill
 

·
Premium Member
Joined
·
516 Posts
I would definitely buy a couple for my d-series engines.
 

·
Registered
Joined
·
504 Posts
Discussion Starter · #4 ·
Thanks for the comments and interest.The Lawn Boy governor kit was always a big seller and the governor collar and spring were the main reason, The collar would wear and the spring would loose tension. That's why I decided to try a different material (bronze) for the collar. It turned out better than I expected. The bronze is not cheap and It would require a lot time and effort for me to produce enough of these collars to sell at a reasonable price.
 

·
The Sea of Green Machines
Joined
·
4,818 Posts
Great job, and fine work. Wow, 318 hours, that would be about 10 or 15 years for me.
 

·
Registered
Joined
·
504 Posts
Discussion Starter · #6 ·
Great job, and fine work. Wow, 318 hours, that would be about 10 or 15 years for me.
Thanks FordTech. Good point about taking 10 to 15 years to reach 318 hrs. I mow roughly 50 hrs a season (year) which is above average and it took me 6 years to get 318 hrs. If I mowed only 25 hrs a year, it would have taken me 12 years for 318hr. Many people don't realize how much time they are actually using their mowers.
 

·
The Sea of Green Machines
Joined
·
4,818 Posts
Thanks FordTech. Good point about taking 10 to 15 years to reach 318 hrs. I mow roughly 50 hrs a season (year) which is above average and it took me 6 years to get 318 hrs. If I mowed only 25 hrs a year, it would have taken me 12 years for 318hr. Many people don't realize how much time they are actually using their mowers.
I used to have two lawns to mow but I sold the other house and now just one lawn that takes about an hour. We get a lot of drought down here so often we only have 2 or 3 months to mow. During a rainy season we get up to 5 months, but that is very rare. Ive had years where I could only mow 8 times.
 
1 - 7 of 7 Posts
Top