Jacobsen lawn mowers

[Houston]

I found this site by accident looking for info on some stationary engines. But anyway, I have an old jacobsen (1960s??) push mower that was used by my dad's lawn service through high school and college. I rebuilt ignition and carb in middle school and used it to mow 10-12 yards a week for during summers until college. I ran it out of gas, squirted some oil in the cylinder, and then put it into storage for 5 years. Last week I finally moved back into a house, and rather than buy a new mower, poured some gas in the jacobsen, and it fired right up second crank. I believe mine is a 20" deck, has wheels on the 4 corners, and did not ever have a self propelled mechanism. Anyone else out there with a similar mower?

[Andrew Mackey]

Does yours have the 2 cycle or 4 cycle engine? I have had both types. Both had the dics type blade with the 4 small cutters. these are reversable. If yours has the auxillary blower fins, so much the better. The trick to these machines is to wakl slowly. They are not speedsters like the plane type blades. Slow and easy does it. You can't ask for a better cutting mower then a Jake! P/S, if you have the 2 stroke, you may have to DeCoke the muffler, if the engine seems weak, or very quiet.
Andrew

[memmurphy]

This mower was purchased used in 1965 by my father. It still starts on the second pull after setting for a year. As you can probably tell, it is a 2 cycle engine. I used it to mow lawns as a kid as well as a trim mower on my grandparents farm. I don't recall the actual engine manufacture. I think I saw a label under the flywheel on the points cover but don't recall for sure the name.

[Houston]

I just finished mowing my new backyard, which had sweets 1-2 feet tall. Cranked up the mower, and it was one of the very rare occasions that I used full throttle. Cut right through everything, never bogged down. I have never had any issues with speed, it will cut as fast as i can push. I have the 2 stroke engine, and decoke the muffler plate about once a year. My mower is a bit older than the pic above i believe, it has a much heavier cast deck.

[memmurphy]

It always surprised me how it would go through the tall grass on the farm and barely bog down. I don't recall that I ever actually stalled it. If I loaded it with too much grass it would just quit cutting instead of stalling. The hardest thing to cut even was dandelions and weeds with stems. My blade does not have any wings on it for lift.

The city back in the 70's used a heavier, probably a commercial grade model that looked similar to mine. The gas tank was larger and as I recall the airfilter on some was mounted on the handle with a tube down to the carb. The deck also looked much heavier. They were two cycle though. They had an arm blade on them. Not sure whether they came that way or if the city modified them. The city mowed around the streams and playgrounds for many years with them. Jacobsen was a good company in their day. IMHO

[Andrew Mackey]

The engine was made by Jacobsen itself. Nice machine! I believe the engine was rated at 2 1/4 HP. With that heavy disc blade, they were hard to stall! The commercial mowers the city used probably had the 521 style engines. They were about 3 1/2 HP, had ball crank bearings and needle bearings on the con rod big end. Remote oversize airfilters, and usually a 3 quart fuel tank, instead of the 1 quart standard model. These commercial machines cut a lot of grass, but the smaller units made a finer cut.
Andrew

[memmurphy]

Thanks for the additional info. Andrew!