Briggs opposed twin engine

SamB

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As I said in the previous post,2 different Intek AVS 17.5 singles have failed me,or should I say they broke themselves(and me,too,$$)!
a couple of years ago,the first one ,for no good reason,snapped the head off a valve right above the stem and the head punched right through the piston. I bought a new Intek 17.5 AVS and put it on the Snapper 33" Extra Tough.
The second Intek 17.5,on my Husqvarna Z42175 zero turn,starting making unnatural rattling noises(death rattle?) so I shut it down,checked the oil. That was OK,so as I was in the far side of the yard,I started it back up and the rattle was back with a vengeance. I quickly shut it down again and towed it to the garage and removed the engine. When I removed the sump part of the case I saw one of the arms that move the AVS weights had broken. Since I mow a much larger area with the zero turn,the almost new Intek got transplanted to the zero turn and the Snapper got parked,engine-less. Till now.
Both of these engines were well maintained,regular oil and air filter changes,using good oil and having never messing with the governor,ran at the factory rpm settings. Both times,the engines were running just as fine as could be....till they instantly weren't.
 

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Scrubcadet10

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Is the IC Twin pressure lubed? (oil filter anywhere)
on the splash lubed twins if you idle them too slow, lubrication has a harder time reaching the top main bearing resulting in wear and the accompanying "chuckle" from the top main when idling.
 

dougand3

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Looks good. I doubt it notices much of a load even when you hit high grass.
 

SamB

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Is the IC Twin pressure lubed? (oil filter anywhere)
on the splash lubed twins if you idle them too slow, lubrication has a harder time reaching the top main bearing resulting in wear and the accompanying "chuckle" from the top main when idling.
Not pressure-lubed. :-( As far as idling, as a matter of course, I run at recommended rpm,both for oiling and for cooling. I've read from many posters that poking around at low rpm hurts both the engine and the hydros. Briggs themselves,say let the governor do it's job and run at or near full throttle.
 

SamB

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Looks good. I doubt it notices much of a load even when you hit high grass.
Nope,it does not notice that clump of fescue! Of,course,the 17.5 Intek didn't either,but the opposed twin does seem to run smoother than the Intek single. That makes sense though,it's a naturally balanced design,unlike the Intek single that has all the extra parts to try to combat the inherent imbalance of the single. The second Intek of mine failed totally due to parts of the AVS system breaking.
The original factory engine on the Snapper was a 11 hp flathead single. It was just a bit under powered for swinging a 33" single blade. The Extra Tough X series 33" mowers were over-built in a lot of areas that the regular Snappers weren't, Gears,axles,etc.so adding a bit more horsepower doesn't over stress anything.
 
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tom3

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My old 18hp flat twin Briggs just sounds good at idle though, sort of lopes like an old Harley. Like to put some straights on that mower but the neighbors probably wouldn't appreciate it.
 

SamB

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My old 18hp flat twin Briggs just sounds good at idle though, sort of lopes like an old Harley. Like to put some straights on that mower but the neighbors probably wouldn't appreciate it.
If you look at my sort of jury-rigged muffler setup on the Snapper,the "chin" muffler works fine wired up the way I have it now. Two lengths of angle off the rear frame box will do away with the baling wire and look, well,morel finished. Just haven'y had the time or have gotten the angle iron yet.
I did toy with the idea of a couple of straight push mower type mufflers,for having dual exhaust,though. I'd bet it would sound awesome. Maybe down the road. This Fall,maybe,with more tinker time.
 

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Hammermechanicman

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First time i have ever seen someone hotrod a Snapper flexiflyer. Out in the barn i have a JD S82 rear engine that came with a 8hp that was worn out so i dropped 12hp briggs in it and i thought that was hopped up. You win.
 

NorthBama

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Nice work plenty of power for that snapper
 
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