# Stihl BR600 seized piston repair



## Duke000088 (Dec 19, 2018)

Hi all, I'm seeking some advice as I progress through a BR600 repair. 

2012 BR600, homeowner use. Always run with TruFuel 50:1. Was running great one minute; then puttered out (I thought it ran out of gas). But on restarting, the pull cord was nearly impossible to draw and a creaky squeal came when it was pulled bit by bit. 

Broke it all down and the piston pin is seized. At first inspection, everything else seems flawless. All the other bearings seemed smooth. I intend to order a new piston kit (comes with new pin and snap rings) but then I noticed one issue: The main bearing on the connecting rod has the slightest amount of play. The two "main" crankshaft bearings on either side are flawless. But on that central bearing where the connecting rod cap would normally be... just an almost imperceptible amount of up/down wiggle. I almost feel like I'm imagining it - its that slight - but its there. 

My question: Could this play in the connecting rod have CAUSED the piston pin to seize? If so, then I'd be wasting time and money if its just gonna kill another piston pin. Or, it seems like being a brass bushing, a toasted piston pin is a pretty common issue on this engine. 

Everything inside seems very well lubricated and looks almost factory new. The unit probably has about 75-100 hours on it. I'd be stunned if this crank/connecting rod bearing could really have worked itself bad... but who knows. 

PS - before anyone asks: I have never adjusted the valves  Didn't know it was a thing until reading here. If I get it back up I'll keep on that job. 

Thanks


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## alexcagle (Dec 20, 2018)

Try looking carefully at the lower rod bearing's cage for damage. 

I've see everal that the upper rod bearing, (which is a bronze bushing), gets hot and seizes, which causes the piston to score against the exhaust side of the cylinder.


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## oman (Jan 19, 2020)

alexcagle said:


> Try looking carefully at the lower rod bearing's cage for damage.
> 
> I've see everal that the upper rod bearing, (which is a bronze bushing), gets hot and seizes, which causes the piston to score against the exhaust side of the cylinder.


Alexcagle, I have a BR600 with the wrist pin slightly seized on the brass sleeve bushinh. I got the piston out and pressed out the bushing. Can you get the bushing or replace it with a roller bearing? Is the crankshaft repairable?


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## Justin Taylor (Jan 19, 2020)

oman said:


> Alexcagle, I have a BR600 with the wrist pin slightly seized on the brass sleeve bushinh. I got the piston out and pressed out the bushing. Can you get the bushing or replace it with a roller bearing? Is the crankshaft repairable?


I have repairs a couple of the br 600s and there is no bushing that I have found but I bet if you look long enough you could find a needle bearing


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## Justin Taylor (Jan 19, 2020)

.


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## alexcagle (Jan 21, 2020)

You can clean them up if they're not galled too bad. Emery cloth works good with a drill. I usually file a slight groove to allow oil a way to get in. 
A small drilled hole in the rod eye might not be a bad idea, but I guess there was a reason Stihl didn't think it was necessary. It's probably caused by overheating.


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