Briggs 725 EXI on my Snapper 21"?

PbBlaster

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This is one of these new types of engines that you don't change the oil,"just add if needed." And no primer bulb, or speed control. Northern Tool sells these for $189.00 with like $17 shipping. 7/8" wide X 3 and 5/32" length drive shaft. Key way is 3/16". Model # 104M02-0197-F1. 163cc
displacement. I am looking for a replacement engine for my 1998 walk behind FRP21600TV.

It originally had a Tecumseh 6hp engine on it; the owner gave the entire mower to me cause he ran it last year without checking the oil level and burned up the engine. He's known I've long been a Snapper fanatic since I've had a late 80's model. I put a new Briggs Intek 6hp engine on mine back in like 1996. That's the engine I swapped over to this '98 walk behind model just within the last two weeks. I replaced the drivebelt with brand new. Not an easy belt to find at your local hardware stores. The drive assembly is flawless and will run you around the block. The only reason I took this mower off my neighbor's hands was cause his father took meticulous care of it. It looked brand new to me. Too bad the son did something so stupid as to run it with hardly any oil it it. I also replaced the wobbly worn out front wheels with steel ones using an assortment of bushings, spacers and washers. What a difference. Not sure why Snapper used such plastic cheap stuff. Not only that, but they appear to be "Snapper" only, like just about everything else. The rear wheels are still ok.

So my Briggs 6hp Intek is showing signs of an oil leak on the left side of the engine in the muffler area. I can tolerate it but eventually want to replace it with a new one.

I question if this particular Briggs engine will fit on the deck or not. The muffler is on the right side of this model, unlike mine that is on the left. I got online with Snapper and did one of these "type and chat" deals. The bozo on the other end said I need to contact Briggs and Stratton. So I tried their 1-888# and that was like trying to get through Social Security. I hung up after 15 minutes.

Any feedback on how reliable this new 725 EXI engine would be welcomed as well as if it will fit my "new to me" 1998 model. If it won't fit, maybe something else will.

Thanks so much for any replies

PB
 
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ILENGINE

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The main issue is to make sure that the new engine has the same crankshaft length and diameter. Some of those Snapper pushers used an 1" crank as opposed to the standard 7/8 crank like most push mowers.
 

PbBlaster

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Well, the Briggs Intek 6hp I put on matched up fine so it must have been similar to the original Tecumseh engine from 1998. Looking at the Tecumseh it appears to be 7/8 but not sure of the length cause the engine pulley and blade drive hub are still on there. I can remove both (hopefully not rusted on) and measure. I'll report back.
 

PbBlaster

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Looks like the Tecumseh that I took off and replaced with my 6HP Briggs Intek (which fit exactly) does indeed have the 25mm (.984" shaft diameter). So, the proper replacement would be the Briggs 190cc model 125P02-0012-F1. Shaft length is 3.156". It's more like my Briggs that's on there. Price is $247.00 vs. the smaller Briggs engine I described previously.

But I still question if this engine will fit on my 1998 21" Snapper mowing deck. I'll see if I can post a pic of what it looks like
 
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PbBlaster

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Original Tecumseh is shown pictured. My 6hp Briggs Intek that I replaced it with is also shown with the clearance around the carb assembly. This new Briggs replacement that has the correct 25mm and 3 5/32" dimensions is shown. I question if the muffler will fit on the deck.P3230005.JPGP3230004.JPGP3230003.JPGP3230001.JPGP3230002.JPGs-l640.jpg
 

PbBlaster

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These new Briggs engines will indeed fit the Snapper 21" Hi-Vac mowers. The guy I spoke with at my local Snapper dealer said the mulching type HI Vac decks have not changed at all since 1998, they are all still the same. I went by and looked at the various models on the showroom floor. Briggs sells the 7.25 163 cc version in both 7/8 and 1" diameter shafts with the 3-5/32" length. The Snappers on the dealership floor all had the larger displacement 190 cc engines with the heavier engine. The 163 cc engine weighs in at 22.5 lbs. The 8.75 190cc engines are 39.54 lbs. in weight. That's a 17 lb. difference. Seventeen pounds is a lot when it comes to tilting the mower up to move it around.

The guy at the dealership also said the 7.25 and the 8.75 is torque, not horsepower. And that the max engine rpms differ. Engines are not rated by horsepower anymore. Not sure which engine to get, I guess it's my preference, less weight with less torque or something much heavier that might not be much of a difference in power. I remember my original Snapper I bought brand new in 1988 had a 3.5 hp Briggs engine on it and that Hi-Vac model had plenty of power to it.
 

Scrubcadet10

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I remember hearing that the 6.25 and 7.25 gross torque engines were rated at round 5 or 5.5 HP.
 

slomo

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Torque is what pushes the blade through the grass. HP is mainly a marketing sales gimmick. I have a 3+ decades old Briggs that routinely embarresses my new'ish Honda GXV160 Commercial engine.

slomo
 

PbBlaster

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Well, my vintage (mfg date 2000) Troy-Bilt Bronco (MTD) rotor-tiller has a Briggs 5.5hp engine (190cc) on it and it will kick your a** if you don't operate it correctly. I think I've made my decision based on my thoughts and contributing feedback. I'm going with the 7.25 series engine that's lighter in weight but will still get the job done. I'm not mowing my entire lawn with it. My riding mower does all that. This Snapper is just for certain areas where the rider doesn't really fit.
 
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PbBlaster

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Using the conversion formula of Torque X RPMs divided by 5252 gives these results in equivalent HP for whatever it may be worth: Multiply the torque by the rpms and divide by 5252. To wit:

Briggs 190cc 8.75 torque series @3600 RPMS divided by 5252 = 5.997 HP

Briggs 163cc 7.25 torque series @3200 RPMS divided by 5252 = 4.41 HP

I remember my original 21" Snapper Hi-Vac that I bought brand new in 1988 had a Briggs 3.5 hp engine on it. It had plenty of power when brand new. That little engine saw a lot of use over a 5-6 year period and got tired and worn out along with some of the self propelled drive components.

So, do I want a 6 hp engine that weights in at 40 lbs., or a 4.5 hp engine that weighs in at 22.5 lbs???. The original Tecumseh 6 hp that I took off this 1998 model weighed in at 22.75 lbs. I didn't know Tecumseh quit making small engines years ago. Maybe that was a good thing.

An almost 18 lb. difference when tilting up a walk behind mower to move it around for the next cut doesn't sound appealing.
 
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