Honda GXV120 rebuild

Chris Parman

Well-Known Member
Joined
Dec 22, 2019
Threads
10
Messages
110
Hello Everyone, I tore down my GXV120 and I took some pictures of initial important parts and surfaces. At a first look at surfaces, from a wear perspective how do the pictured look? I just need some advice on replacing or reusing?. Secondly, from a piston perspective replacing piston and rings (keeping standard specs) and just hone? Or a complete bore and hone? Thank you in advance for you help.

20200208_170412.jpg 20200208_173720.jpg 20200208_173728.jpg 20200208_173742.jpg 20200208_173750.jpg 20200208_173757.jpg 20200208_173844.jpg 20200208_173848.jpg 20200208_173855.jpg 20200208_173902.jpg
 

tadawson

Well-Known Member
Joined
Mar 20, 2019
Threads
0
Messages
148
Reuse any and everything that is within service specs . . . might just need rings and a light deglaze/hone, but wom't know until you measure it. Considering age, I would def. replace all seals though . . . My GXV140 were so dry, aged, and shrunken they they pretty much fell out . . . and the 140 is even older . . . Seals are cheap, and you are there!
 

Chris Parman

Well-Known Member
Joined
Dec 22, 2019
Threads
10
Messages
110
Reuse any and everything that is within service specs . . . might just need rings and a light deglaze/hone, but wom't know until you measure it. Considering age, I would def. replace all seals though . . . My GXV140 were so dry, aged, and shrunken they they pretty much fell out . . . and the 140 is even older . . . Seals are cheap, and you are there!

Tadawson, thank you for the reply. By the way, before I tore the engine down it was blowing white smoke however the white smoke dissipated after it the engine warmed up. When it ware warmed up is was blowing less white smoke (if that makes sense). Let me know your thoughts.
 

tom3

Lawn Addict
Joined
Apr 9, 2018
Threads
25
Messages
1,579
I'd ring it and run it. New seals and gaskets. What kind of oil are you running in it?
 

Chris Parman

Well-Known Member
Joined
Dec 22, 2019
Threads
10
Messages
110
I'd ring it and run it. New seals and gaskets. What kind of oil are you running in it?

tom3: When I bought the HR214 (a month ago) I changed the oil and used 10W-30 (Conventional oil). Even after the oil change it still blow white smoke and today I tore it down.
 

tom3

Lawn Addict
Joined
Apr 9, 2018
Threads
25
Messages
1,579
One thing you have to watch on these air cooled motors is the oil rating. A lot of the 10w30 oils are not correct for that type of use. Might explain some of the wear showing on the aluminum parts. If you have a user's manual look for the API rating required. Probably not the SM or SN as most of today's automotive oil is rated. Actual Honda, or maybe Kohler 10w30 oils might be best for that.
 

jp1961

Well-Known Member
Joined
Jul 22, 2013
Threads
39
Messages
785
Hello,

From your pics, the internals don't look too bad. These dimensions are listed in my Intertek manual for the GXV120, standard cylinder bore diameter is 2.262" - 2.363" cylinder bore diameter. Standard piston diameter measured at the lower edge of the skirt and 90 degrees from piston pin bore is 2.360" - 2.361". Valve stem to guide clearance is .001" to .002". Standard valve guide inside diameter is .2165" - .2170". Standard valve spring height is 1.339". Standard rod journal inspection for automotive use was to rub a penny (an old copper one not the new copper plated steel ones,,,lol) on the journal, if any copper is deposited, journal needs polishing. Let me know if you need another dimension not listed. I would lightly hone and install new rings.

Regards

Jeff
 
Last edited:

tadawson

Well-Known Member
Joined
Mar 20, 2019
Threads
0
Messages
148
Tadawson, thank you for the reply. By the way, before I tore the engine down it was blowing white smoke however the white smoke dissipated after it the engine warmed up. When it ware warmed up is was blowing less white smoke (if that makes sense). Let me know your thoughts.
That's what my 140 was doing . . . . deglaze/ring/seals, and run it (unless you find something else). The sleeve in these Hondas seem to hold up quite well.
 

ILENGINE

Lawn Pro
Joined
May 6, 2010
Threads
39
Messages
9,854
Cylinder still shows a hint of cross hatching so very little wear there, but there is evidence of hot spotting so need to deglaze and new rings.
 
Top