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427435

The 7790 is running again!

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427435
Finally got things back together and fired it this afternoon. Seemed to run OK once some of the assembly oil got burned off and the fuel lines got well primed. Decided to put some load on it to break the rings in, so I put the snow thrower on it from the 917. Now the 917 actually has been re-powered with a 20 hp Kohler and runs the snow thrower well, However it deep, heavy snow, I need to feather the hydro back to keep the engine from bogging. Once I got everything switched over to the 7790, I hit some snow along the side of the road that was packed. The Lombardini didn't slow down-----but all of sudden the drive belt started slipping. That never happened before with the 20 hp Kohler. Either the HP of the Kohler is exaggerated a bunch or the Lombardini is grossly under-rated. Put some belt dressing on the drive belt and finally got the diesel to work a little. The start-up oil is now draining and tomorrow will be another play-day!! :D

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acfarmer
Its probably a matter of torque the gasser pulls down RPM when it hits a hard spot the diesel doesn't.Each engine's cam sets the RPM range it pulls at the best or its 'Power Range'.

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UCD
The 7790 diesel is a workhorse. The 18½hp lombardini diesel is more like a 25hp gas engine. It will run circles around a 20hp Kohler. I almost traded my 7790 for a 20hp Sunstar, glad I got to try the Sunstar first. Where the 7790 was just working the 2hp Sunstar was dieing and stalling. The diesel could do twice the work in half the time with a lot less fuel.

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427435
Torque comes into play when an engine pulls down its rpm. The belt friction was enough to pull down and stall the Kohler (if I let it), but not the Lombardini. It didn't even loose any rpm. I think the Lombardini just has bigger horses on its dyno than Kohler.

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UCD
The only time my belt would slip was if it got wet from snow. Otherwise the engine would stall before it slipped. The Lombardini is hard to stall but I have done it.

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427435
Put in fresh oil (again) and switched the tire chains from the 917 over to the 7790 (got stuck the other day without them :(! ) Then I went snow blowing to again see what it would do. Headed out into my lawn that had about 15" of snow pack (several snow falls and a couple of melting days). I had also put belt dressing on the belt the other day. Yes, you can stall the diesel, but it's not easy to do. And the blue smoke is gone!! :D

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dlcentral
The 1st of my 920 diesels I bought at a dlrs,when I tried the mower deck,it was siezed but that som beetch eng didnt even slow down I was sold on them ever since,,.

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