v series engine blew tonight

briggs206

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I was mowing with my lawn boy for about 20 mins tonight and it was running great then out of the blue it died and seized up. I let it cool and it will turn now but I looked in the exhaust and the piston is fryed. will the bore usually clean up or is it most likely junk? will an f series piston work in it if it isn't totally junk? the v pistons are expensive but the f is only 22 bucks. iv about had it with this pile of crap mower. I even mix the fuel rich too. my briggs runs no matter what but for some reason I keep wasting time with these junk lawn boys....
 

gfp55

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I was mowing with my lawn boy for about 20 mins tonight and it was running great then out of the blue it died and seized up. I let it cool and it will turn now but I looked in the exhaust and the piston is fryed. will the bore usually clean up or is it most likely junk? will an f series piston work in it if it isn't totally junk? the v pistons are expensive but the f is only 22 bucks. iv about had it with this pile of crap mower. I even mix the fuel rich too. my briggs runs no matter what but for some reason I keep wasting time with these junk lawn boys....


Maybe some of the LawnBoy junkies (no offence) will read your thread and be able to help you with your mower. Sorry to hear of your problems with the LawnBoy. Good Luck.
 

Phototone

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Are you SURE the piston is fried? You know they all look pretty yucky thru the exhaust port. Do you have compression? Possibly you could just replace rings if the bore is not bad. Alternative, would be to buy a "junker" mower, plenty of this model around, I found one myself (a DuraForce) at the local scrap metal yard and bought it for the price of scrap steel by weight.
Just about the only reason it would have seized up, is if you didn't have 2-cycle oil mix with your gas. There is just almost NO REASON the piston would seize up if the oil-fuel mix was correct. Don't junk it, these mowers are twice the mower of anything you can buy today (in my opinion) and compared to 4-cycle engines, they are SO EASY to rebuild.
 

briggs206

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ok I disassembled her tonight and yes the piston is smeared down the sides. the bore cleaned up well tho. the weird thing is the internal parts were extremely oily so I don't know why it would have seized. oh well, I guess if I can find a piston I will rebuild it to live on. I cant let this thing beat me. question is, where do I get a v series piston? I can only find it with the rod and they are $160! can I use an f series piston?
 

turfboy1997

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ok I disassembled her tonight and yes the piston is smeared down the sides. the bore cleaned up well tho. the weird thing is the internal parts were extremely oily so I don't know why it would have seized. oh well, I guess if I can find a piston I will rebuild it to live on. I cant let this thing beat me. question is, where do I get a v series piston? I can only find it with the rod and they are $160! can I use an f series piston?

F and v internals are the exact same, so yes any f series piston and rings will work. The v's are notorious for vibrating themselves to death. might want to check your upper, lower and connecting rod needle bearings for slop. The connecting rod to crank bearings usually have 32 in them. OMC always put 33 in the f engine, so any motor that i rebuild gets 33 and it seems to tighten things up and make them run like new.
 

Phototone

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F and v internals are the exact same, so yes any f series piston and rings will work. The v's are notorious for vibrating themselves to death. might want to check your upper, lower and connecting rod needle bearings for slop. The connecting rod to crank bearings usually have 32 in them. OMC always put 33 in the f engine, so any motor that i rebuild gets 33 and it seems to tighten things up and make them run like new.

F and V internals the same!! Wow, that is very good to know, as rings and reproduction pistons for F series are very cheap. I have always felt that the real "reason" for the V series was to make the whole mower more cheaply.
 

briggs206

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thats good to know. the rod lower bearing seems to have a gap between the needles so maybe I should tighten it up. I have to admit the v has a lot of power but yes it was missing some bolts when I got it. im ordering a piston tonight and il hone the jug. thanks for the info, I cant find a v specific piston so I will use the f. also- should I flip my reed while im in there? and what sealer should I use on the halves?
 
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