Rod thrown

Danelawnmower

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My Briggs and straton threw a rod and left a nice dent. Anyone believe the dent could be ignored if I replace the rod?02A90EEF-BEFB-44C3-9AEB-BE7B07515B6F.jpgB8C25DF0-A958-4350-A8AD-6D351E2AF054.jpg
 

Pumper54

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My Briggs and straton threw a rod and left a nice dent. Anyone believe the dent could be ignored if I replace the rod?View attachment 39915View attachment 39916

It looks like that chip is below the piston skirt area on the cylinder and I really don't think is will be an issue, what I do see that bothers me is the deep scoring in the cylinder wall. What does the piston and crank look like? Are you going to hone the cylinder before setting up the new piston, rings and rod?
Tom
 

Russ2251

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Nothing to lose except the cost of a rod and your time.
Scoring looks minimal to me. I can see most of the original cross-hatching...which is a good thing.
If it were my decision I would not hone.

The only question is why was the rod thrown to begin with. Do you know?
 
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bertsmobile1

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I am with Russ,
Rods do not throw for no reason.
I see deep wear in the top of the lower crankcase bush ( hole ) which looks to be deeper on one side that the other indicating the crank is running a little crooked.
If you decide to refit the rod get a die grinder / dremel tool etc in there and get rid of the cracks in the liner and smooth off the edges of all of the damaged areas,
You might need to put a thrust washer under the crank if the wear previously mentioned causes too much end float.
So clean everything up bolt the cases together and see what end float you have.
Also check for side to side movement in particular front back , the bets pull the crank forward so you get more wear at the deck side than the cylinder side.
Any movement and we are talking .0005" or more and the bearing region is trash.
Too much end or side float can cause rods to break but generally the little ends go.
You can fit a phos bronze top hat bearing to reclaim the block but it requires you to know a friend with a taster for free burbon.

If you want a better diagnosis we need to see the fracture surfaces VERY CLEARLY & IN FOCUS plus the journal on the crank plus the inside of the piston.
IT might be a trick of the photo but it looks like that liner has shifted so put a strait edge across the head area and check.
If the liner is above the alloy then the block is trash.
My name is not Judy so I am not here to judge, but we need to have a chat about your maintenance regieme
 
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