That original engine (28T707-1121-E1) is rated at 13.0 Gross HP by Briggs spec sheet. Briggs Power Portal has the 219907-3026-G5 at 12.5 Gross HP. Briggs does list the one above as a direct replacement but I would very leery of it hp wise. I have seen 210000 series rated as low as 10.5 hp and they are gutless wonders at that rating.

Personally if I was replacing a 13.5 Hp L-head I go with the 310000 series rated at 15.5 Gross HP through I have seen them label anywhere from 15.5 to 17.5 Gross HP. I one rated at 15.5 hp on my 38 inch cut Bolens and one label at 16.5 hp on my Yard Machines 42 inch cut; same engine parts wise. The one on the Yard Machines is way under powered as need to slow to a crawl when cutting slight tall grass when compared to the Bolens that cut grass as tall as the hood if travel slowly. That is why I go to put a 21 gross hp on it this year if I going to keep it for my personal use; just to change engine pulley and belts size. I just look at why lose 7 cubic inches when I can go up 3 cubic inches.

Looks great on paper EPA wise as the 21 cu in does use less fuel. Something else to think about too that Gross HP is usually rated at 3600 rpms and both the 28 and 21 being talked about here are set at 3400 rpm max.

The new SAE J1940 standard requires all engines produced after and including October 1, 2013 must be within 95% of the declared rated power and torque as opposed to the old standard of 85%. SAE (Society of Automotive Engineers) has also stated that the engine manufacturer must disclose the rpm for rating and with the GROSS (SAEJ1995) or NET (SAEJ1349) horsepower.

This because of so much mis-info on the actual Gross HP over the years and the manufactures were even sued about it years ago. That they went with Ft-lb torque specs but I see they are creeping back to HP rating again. Still gives problems when replacing engines. So when replacing a pre 2013 engine go with 85% of the labelled Hp and compare to 95% of the new replacement engine and there is still no guarantee that you would have enough power; hence, why I usually up size the engine to next size whenever I can.



Last edited by AVB; 29/01/17 09:59 AM.