July 23: update feat. old Lawn-Boy mower

My old Lawn-Boy has got its power back.  What a voyage of discovery it was, tracking down the problem and fixing it.

Hello!  I’m sorry I’ve not been more communicative in July; of course I have excuses.  Up until last week, I was working on my old Lawn-Boy mower, trying to get it running right.  I finally succeeded.  However, my wife’s also in courses, so there’s more to do around the house as well.  It’s all good; I just haven’t gotten time to post.

We had a few weeks of hot, dry weather, but that’s changed this week.  It’s raining right now.  The lawn needs it; I don’t water much in the summer.  The water restrictions were heightened a while back, but I think they’ve eased off since.

Of course, my first-born son, Paul, turned 12 on the 18th.  It’s a big birthday, turning twelve.  He’s wearing it well.  Today he and James are away at camp.

I raked our front cedar chip area last week, pulling out the weeds.  That’s a lot of work.  I’ve been doing a few extra housecleaning projects lately as well.  Such activities, combined with my workouts, are keeping me in shape.  My weight is unknown, however:  when I cleaned the bathroom scale, it went silent.  It’s electronic:|

Now, to the lawnmower.  First things first:  it’s been very hard to get exact information about it.  I’ve been through the LawnBoy service manuals and such, but this mower definitely seems an oddity.  What’s more, the closest model to it, according to my research, seems to be the 4531 from around 1980. (I first found connection with the help of mytractorforum.com.)  However, I remember when the lawn mower was bought: I’d say it was in ’79 or even ’78.  Its precise engine model – d415 – seems rare.  The fuel system is one kind on the outside, but its internals include parts from an earlier kind (I took the carburetor apart).

My father-in-law helped me identify and order the new crankcase seal, which came, ultimately, from Montreal.  It cost $7.  However, it didn’t turn out to be the only problem.  Next I cleaned the air filter, though it looked pretty good.  Not surprisingly, the motor still bogged down.  Finally I unhitched the carb, took it apart, and gave it a good cleaning.  When I reassembled the mower, it ran perfectly, starting on the third pull. I ran it through some thick clumps of grass, but it ate them up; it had regained its former vigour.

I read in Wikipedia that the d415 motor was made by the Johnson-Evinrude company.  Here are a few pictures of the mower, up on my improvised worktable.  If it is from 1979, this is its 35th year of service.



Thanks to all the good people whose web pages and videos I watched in order to troubleshoot and fix the problems with this mower – and to my father-in-law, as well. Thanks to my father, too: he gave me the old mower when I bought this house. It’s the only gas mower our family owned when I was a kid. Now it starts within three pulls most times, and, once again, powers through the thickest patches of the lawn:)

Hopefully, I’ll be able to post again soon. Cheers.

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