New to me HR-21 bogging a bit

[jeseely]

Hi folks,

I picked up a super clean HR-21 yesterday after the spark plug threads in my old freebie Toro Super Recycler tore out of the head (I suspect they had been cross threaded and tapped before). Absolutely love the mower, easiest starting of any I've owned, strong self propulsion, and really delivers a perfect cut.

Anyway, the one gripe I have about it is it seems to require a fairly long warm-up period before I can take it off choke to "high" idle. If I do it too fast, it will die. The second, possibly related, issue is that I seem to have to gingerly engage the blade again after I stop and let it idle for a second. If I re-engage the blade it will either bog down or sometimes stall out.

My first thought was compression, being 40 years old, but it doesn't smoke at all, and I mean not at all, which is a first for me even with newer high quality mowers. Any suggestions where to being trouble shooting? Being so old I am not finding much info on these mowers other than folks waxing poetically about how great they were!

 

[mechanic mark]

Honda Power Equipment Lawn Mower OEM Parts, CyclePartsNation Honda Parts Nation

Shop our large selection of Honda Power Equipment Lawn Mower OEM Parts, original equipment manufacturer parts and more online or call at 269-385-1540

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locate your serial number on mower for parts. Yes I would check compression first, check for gas in oil by smelling dipstick for gas, use Honda OEM parts, replace spark plug, air filter, change oil & use a quality brand 10w-30 or 40 Valvoline, Pennzoil, etc., replace carburetor they are inexpensive & use 93 octane gasoline, check out blade for sharpening, balancing or replacement. Let us know how it goes, thanks, Mark

 

[tranchinh]

I having trouble to find a carburetor for this one HR21 .May try to modify GCV carburetor to use on this

 

[Tinker Ty]

I am leaning towards a compression issue, jeseely. If you have a compression tester, use it to find what you got. Otherwise, the bohemian method is to squirt a small amount of oil in the spark plug hole (down into the cylinder). Replace spark plug and attempt start and if condition improves (minus the smoke you get), then you have a compression issue. Good luck. Keep us posted.

 

[tranchinh]

Hi folks,

I picked up a super clean HR-21 yesterday after the spark plug threads in my old freebie Toro Super Recycler tore out of the head (I suspect they had been cross threaded and tapped before). Absolutely love the mower, easiest starting of any I've owned, strong self propulsion, and really delivers a perfect cut.

Anyway, the one gripe I have about it is it seems to require a fairly long warm-up period before I can take it off choke to "high" idle. If I do it too fast, it will die. The second, possibly related, issue is that I seem to have to gingerly engage the blade again after I stop and let it idle for a second. If I re-engage the blade it will either bog down or sometimes stall out.

My first thought was compression, being 40 years old, but it doesn't smoke at all, and I mean not at all, which is a first for me even with newer high quality mowers. Any suggestions where to being trouble shooting? Being so old I am not finding much info on these mowers other than folks waxing poetically about how great they were!

Unlike other Honda lawnmower HR21 use GV150 engine ,not overhead valve,its flat head and only 3.5 horse power .I found that its difficult to work on it as parts is hard to find and too expensive .Last time I work on this mower still can 't get it run right,running too lean

 

[upupandaway]

If u guys want some parts, I parts from this sitting around:


PM me and ill send u pics of the parts i have.