seized tecumseh vtwin

[38racing]

an acquaintance called and told me he thought that he blew his engine. He said it just stopped and restart attempts it would not crank. Breaker wrench on flywheel nut won't turn it. Oil was black but still at proper level. Although it has a fuel pump , the gas level in tank is well above carb when full (which it is but sitting now at my place fuel level in tank has not gone down and oil level not changed). One shop told him seizing was common on these engines. Maybe the oil pump fails? I doubt that it would be a thrown magnet that's jamming it. I might have a 20 hp briggs 407777 to offer him but he's a bit concerned that his was a 25 hp driving a 54 inch deck. I figure he could always cut 8" less width on each pass.

[KE4AVB]

Need the engine numbers here as I am not that familiar with the Tecumseh engine and I usually relies the IPLs and service for troubleshooting. There is only one way to start diagnosing this if it was in my shop and that would be to remove all external loads and then work my way in checking for obvious problems as I go through the disassembly. I know a lot work but sometimes it takes it to find the culprit.

As for dropping from 25 to 20 hp on a 54" I wouldn't try it as it will probably stall out from the initial start-up load. I have had several of these larger decks in the last couple years and even at 25 hp these seems under powered to me especially at start-up. Oruga Ogura has develop a soft start system for their PTO clutches which could allow the use of a smaller engine but the mower manufactures have been reluctant to use it. This might be well founded as it could cause excessive wear on the clutch disc; although, Oruga says it is within normal safe slippage rate. I tried getting Oruga Ogura to send an unit for testing but they just failed to follow through on their offer.

[38racing]

I was thinking that if 20 HP would cut 46" of heavy grass then it would get 54" going if out of grass and then he might have to cut slower or narrower.

[38racing]

Wondering how to remove the flywheel. No holes for a puller. OK found I need the knockoff tool or several 3/4-16 nuts.

[38racing]

Wondering how to remove the flywheel. No holes for a puller. OK found I need the knockoff tool or several 3/4-16 nuts.

I was able to pop it without the tool. Now have to remove coils to get clearance to lift it off.

[bgsengine]

Also check to make sure no twig or stick jammed up in between the engine pulley and the frame - Got a free 3 year old tractor once that way when someone told the guy the engine was set up, so he asked me if I wanted it for parts.... few months later after starting to tear it down, found the stick (3/4 inch diameter) jammed up in there, When I called him back with the info that it was just a piece of wood jammed in the pulley and I could fix it for him, he just said "keep it, I already got a new one"

[38racing]

unfortunately I have it all apart and it was not a flywheel magnet. I have a lead on a motor exactly same with same ~400 hours for $350 but wonder how long it will last. I should ask him how often he changed the oil and what grade?

[HondaG100]

As for dropping from 25 to 20 hp on a 54" I wouldn't try it as it will probably stall out from the initial start-up load. I have had several of these larger decks in the last couple years and even at 25 hp these seems under powered to me especially at start-up. Oruga has develop a soft start system for their PTO clutches which could allow the use of a smaller engine but the mower manufactures have been reluctant to use it. This might be well founded as it could cause excessive wear on the clutch disc; although, Oruga says it is within normal safe slippage rate. I tried getting Oruga to send an unit for testing but they just failed to follow through on their offer.

I assume you meant Ogura? Newer engines may be overrated on horsepower but my 80s era 52 inch Grasshopper will mow tall grass with an 18 hp. Briggs opposed twin. I see many mowers now with 25 or more hp and I can only assume it is easy to build a slightly bigger engine which catches the eye of the shopper. JMO but unless you are running a huge deck or doing commercial mowing at 15 mph you do not need that much power.

[KE4AVB]

I assume you meant Ogura?

Yep Misspelling on my part; fingers got crossed up. I go back and correct the spelling. Still not to bad for someone that didn't type other then hunt and peck until a few years ago. I even repaired electric typewriters for ten years and never learn to type. I just didn't have the time back then.

I agree the new engine ratings are confusing. As for 18 opposed I think it is the way it configured that helps as the way it fires with the cylinders firing at 180 degrees instead 270 degrees which I would think would be a smoother power balance but I no engineer either.

I also have seen the 18 hp opposed engine be label as 18.5, 19.5 and 20.5 on Craftsman mowers. All the same model number just different type numbers. I probably would not had notice it but I had all three in for repairs the same week.

[HondaG100]

I also have seen the 18 hp opposed engine be label as 18.5, 19.5 and 20.5 on Craftsman mowers. All the same model number just different type numbers. I probably would not had notice it but I had all three in for repairs the same week.

Didn't Briggs get in trouble a few years back for labeling the same block with different HP ratings and selling them at different prices? As I recall from a conversation with a dealer it was on a smaller mower engine.