Briggs & Stratton Piston Ring Install Question

mikesiegel

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I purchased a set of OEM piston rings from Jacks for my Briggs 6.75 HP engine. Ring set part number is 791969. The instructions in the box say to install the ring with 2 stripes on the edge in the middle piston groove and the ring with 1 stripe in the top groove. Unfortunately, the rings both have only one stripe. 1 ring has a single red stripe and the other one has a single pink or coral stripe. The ring with the pink/coral stripe has an O stamped in white on the top/bottom of the ring. Pictures are attached.

Did I get a set of rings that maybe was boxed improperly? Any advice would help please.

Thanks - Mike
 

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mikesiegel

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I purchased a set of OEM piston rings from Jacks for my Briggs 6.75 HP engine. Ring set part number is 791969. The instructions in the box say to install the ring with 2 stripes on the edge in the middle piston groove and the ring with 1 stripe in the top groove. Unfortunately, the rings both have only one stripe. 1 ring has a single red stripe and the other one has a single pink or coral stripe. The ring with the pink/coral stripe has an O stamped in white on the top/bottom of the ring. Pictures are attached.

Did I get a set of rings that maybe was boxed improperly? Any advice would help please.
I forgot to mention that the ring with the red stripe has a bevel on the ID and the ring with the pink stripe and O stamp has no bevel.

Thanks - Mike
 

slomo

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I space the ring end gaps 180 degrees apart, far as possible. So 0, 180 then 0 degrees for all three rings.

Heard some do like 120 degrees. Don't know if that is correct.

You need to measure these gaps making sure you have enough clearance. Engine manual should have gap specs.

slomo
 

StarTech

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The one with the inside bevel is usually the top ring and the bevel goes toward the piston crown.

And 120 degrees is normal as you want the gaps evenly spaced on install.
 

Rivets

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I’ve always taught the ring end gap should be 120 degrees apart if you have a single oil ring and 180 degrees apart if you have a three piece oil ring. With a three piece oil ring, you position the oil scraper ring gaps 180 degrees apart, 90 degrees from the compression ring gaps. This way all gaps are a maximum of 90 degrees from each other.
 

StarTech

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Makes sense.
 

slomo

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I'm sure the rings don't say where they were put. Over time and use.......

slomo
 

bertsmobile1

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I'm sure the rings don't say where they were put. Over time and use.......

slomo
Rings rotate in the grooves unless they are pegged .
The spring of the ring does not create the compression, it is the gasses trying to get past the ring which forces them out to make the seal with the oil on the bore & in the ring groove .
This is why on 4 strokes champhers always point up.
When new the rings have not made their seal against the bore so spacing them 120 degrees helps the initial compression.
Put them all in a row & try to get the engine to fire.
IT can be done but you need to crank the engine over near full operating speed to do it .
 
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