To hone or not to hone

[ghostrider20]

1980 Briggs 3hp horizontal shaft go kart engine.

Have been reading many threads on whether or not to hone, most say no. I'm reviving my childhood go kart and got the engine running and although no smoke, it is fouling plugs and there is oil on top of the piston. Tore it down and found the cylinder to have .002 wear and no ridge. Cylinder has no gouges, scratches or wear marks. The cylinder has .001 taper. No cross hatching present.

The old rings have huge gaps (installed in cylinder and measured).
compression ring - .060
Scraper - .056
Oil - .110
Piston looks pretty good, the chrome is worn in some areas. I have a new old stock std piston to use.

New old stock piston rings (standard size) measure:
Comp = .017
Scrap = .19
Oil = .20

I bought a set of new std. size piston rings (Briggs brand) but the comp ring was rectangular and the original was tapered on the top inside. So I purchased a new old stock set and that matched the original ring. Is the newer ring better than the original with the tapper? I'm inclined to put in what came out?

Thank you for any advice and guidance.
Mark

 

[Auto Doc's]

When installing new rings, always hone the cylinder with a fine grit hone. Honing will "break in" the new rings so they conform to the true cylinder diameter.

Without honing it will introduce oil consumption. The "crosshatch" pattern that honing provides, prevents oil from having a straight path to escape past the piston.

Very important: wash the cylinder and inside of the engine block with plenty of soapy water to remove any honing sludge. Simply wiping the cylinder out is not proper cleaning and will lead to trouble. Most of the time I use a gas-soaked rag with a brush and then the soapy water.

Make sure to "clock" the rings so the end gaps are not aligned with each other.

Use the following technique: Use a black marker to make "tick" marks every 90 degrees on the piston top A simple plus sign (+) across the piston top also works.

1st ring at one mark (0-degree), 2nd ring at the opposite mark (180-degree) and use the other 2 marks to align the thin oil rings, so the gaps are opposite of each other at the 90-degree mark, and 270-degree mark). The oil ring expander gap should not be in line with any of the other ring gaps.

A small engine piston ring compressor is highly recommended. Install the piston with a light coat of clean oil applied to everything, then tap the piston down in the bore with a hammer handle. Make sure not to hit the crank journal at the wrong position. Seat the connecting rod slowly then install to rod cap, torque the bolts and bend the lock tabs up if it has them.

Aside from that I recommend you run an SAE 30 oil during break in and change it after 8-10 hours of initial run time. From there 10W-30 would be fine for most climates.

A note about the rings: They usually come with a small paper that indicates which ring design is compatible with each ring groove location. Some had a simple dot that always faced up and others had a taper on the inside that would face up. Older ring design even had a square ridge cut on one ring, so it acted as an oil scraper.

 

[ghostrider20]

Thank you. My concern is with the notation in the Briggs manual which states not to hone or remove glaze, but is mentioned in conjunction with the use of chrome rings.

 

[Rivets]

The Briggs service manual says you can hone the cylinder if you have the proper tools. I’ve done it many times over the years and if you are just wanting to just redo the cross hatching, I would recommend using a fine grit ball hone. Make sure you have one for your cylinder, aluminum or cast iron. You just want to break the glaze and add a little hatching. After after completed I always told my students to wash the block three times with dish soap. Dry with facial tissue and if you see any black residue, repeat the washing again. If you have a cast iron cylinder, immediately coat the cylinder with oil to prevent oxidation. Here is a service manual. http://www.tuks.nl/WFCProject/img/E...210-Briggs-Stratton-Service-Manual-L-Head.pdf

 

[Hammermechanicman]

I have a 320 grit ball hone designed for cast iron and works well. I have used it on aluminum for a few seconds and had good results with regular rings.

 

[ghostrider20]

Thanks for the input and recommendations. I used a fine 3 stone hone and put a nice cross hatching on the cylinder. Cleaned, then cleaned some more, then cleaned even more. Installed the NOS std. bore piston and ring set. Compression check showed 110 psi.

Ran it for 10 min varying loads then let it cool for several minutes. Repeated this cycle a few times and changed the oil.

It once again will spin the little tire in a turn and leave a burnout, just like when I was 7! Kids are having a blast.

 

[Craftsman Garage]

Makes me want to make a go cart out of my 70s Honda generator engine (G100)