The engine is constructed predominantly of 1″ square steel tube with 1/16″ wall thickness. The only larger tubes are the two base pieces that run front to back; these are 1.25″ square tube. Here most of the tubing has been cut to length and tack welded in place.
All the structural pieces are now complete. The stand is very rigid now.
I’ve welded another piece of 1″ square tube across the top front of the stand. This will become the upper radiator mounts.
The middle portion of the tube has been removed, leaving two stubs on the sides to hold the radiator mounts. Shorter tubes could have been welded directly in place, but starting with a longer tube and then cutting out the middle ensures better alignment.
There’s another stub on the rear bottom of the radiator that’s not visible here. The radiator is currently being test fit. It will sit right in front of the engine about 6 inches in front of the propeller.
2.25″ steel circular tube with 1/8″ wall thickness, and large washers that will form the feet of the stand. The washers were originally coated with zinc, but I’ve removed the zinc plating with a grinder. If you’re doing any welding with zinc plated parts, all zinc must be removed as the zinc releases a harmful gas when heated.
It’s not pretty, but it should hold.
One of the feet welded to the engine stand. The feet are designed to use 2″ diameter rubber dampeners around 1/2″ bolts.
This is the HTD pulley set for the reduction drive. The top and bottom pulleys have 90 and 36 teeth, respectively, for a reduction ratio of 2.5:1.
The pulleys and belt (HTD 8 mm pitch, 30 mm belt width) temporarily secured to the stand. At this point the belt is loose, because the tensioner has not yet been added.
The 4 mounting legs have been bolted to the Suzuki engine, and the flywheel adapter and shaft are also attached.
The Suzuki engine sitting on the stand for the first time to check alignment.
The alignment checks out pretty well. It’s going to look great painted and bolted to the craft!
This is the tensioner pulley I’ll be using to tighten the reduction belt. The shaft is a piece of 1/2″ threaded rod secured to two pieces of steel angle.
A piece of steel angle has been welded onto the stand. This will be used to secure the belt tensioner.
The tensioner assembly attached to the stand with two pieces of 1/2″ threaded rod. To tighten the belt, the bolts closest to the camera are loosened one turn, and the bolts on the other side of the steel angle are tightened by the same amount, pushing the pulley assembly inward. This process is repeated until the desired tension is reached. The 1/2″ threaded rods are very short at the moment. These lengths were for test fitting; thy will be exchanged for longer rods later to allow for more adjustment.
The HTD top pulley and belt. Notice the tensioner pulling the belt taught.
The engine has now been removed, and I’ve carefully stripped the oxidized layer from the steel with a sanding flap wheel on the angle grinder. It’s now ready for primer and paint!
I used high temperature engine enamel (dark brown) for the engine stand, as parts of the stand will become fairly hot while the engine is running and normal spray paint will flake off. It’s now ready for the engine, radiator, and tensioner to be reattached!