Replacing the Engine on a Snapper - Part 2
You CAN replace a Tecumseh engine with a Briggs and Stratton - my lawnmower is living proof. I will say that installing the engine was a whole lot easier than finding the right one to buy. I had to do lots of research on the internet, not to mention several phone calls and dozens of Emails. If there are any experts out there, I never found one.
I have a Snapper Super Six self-propelled mower with a Tecumseh engine from the 1990's. That engine lasted over 15 years, so I guess I got my money's worth out of it. The output shaft is 25mm diameter with a woodruff key near the top that drives the self-propelled mechanism. Tecumseh is no more, but I figured all I needed to do was find an online manual that would show my old engine and the replacement Briggs engine. Failing that, surely Snapper must have that manual, either online or in paper form, right? Wrong! Snapper would not even talk to me when they found I was trying to replace a Tecumseh engine; they referred me to a replacement engine company.
Surely a replacement engine company will have knowledgeable people who can tell me right away what engine I need? Wrong again! The technician from that company looked up my old Tecumseh engine, told me that I had a 1" shaft, and said there was no possible replacement from Briggs. This was in spite of the fact that I had miked the shaft size at 25mm at two different places using two micrometers and a vernier calipers. When I asked him to please provide the exact shaft size and position of the woodruff keys on a 25mm Briggs shaft, he told me that there was no actual inventory at his location, and he could not tell me anything about Briggs engines except what was on the spec sheet.
The ideal situation would have been to take the old engine to a somewhere where they sell new engines, and compare the two to ensure a good fit. That is more easily said than done. The local repair shops said they did not have any engines in stock, but could order me a new one. OK fine, but I can do that too. The only place I have ever seen that sells engines and actually has them displayed is a mid-western hardware-store-on-steroids called Fleet Farm. None of those in PA.
After many internet searches, I finally found a drawing of the appropriate Briggs crankshaft, and verified that one of the woodruff keys on it was at the proper position on the shaft. I then found pictures of the engine on the internet as well as external drawings from Briggs showing overall dimensions and where the mounting holes are. I was then able to verify that the engine would fit. In retrospect, it makes sense that Briggs and Tecumseh engines are similar - Snapper used both brand of engines, and would not have designed the mower around a specific engine. Installation took less than an hour, way less time than it did to find the engine in the first place.
When I was a kid growing up in the 1960's, my Granddad had a motorized reel-type lawnmower in his barn. This type of mower was popular in the 1940's and 50's. It was broken and he was not able to find parts, but he couldn't bear to throw it away either. If it was this difficult today with the internet, it would have been impossible back then without it.