Grasser Marine Engine – Part 2 of 2

It's time to cut new gaskets for the crankcase and make a new cart for the Grasser marine engine.

| August/September 2016

  • Dave Irey's circa-1907 Grasser marine engine.
    Photo by Dave Irey
  • Fitting new gaskets to the crankcase.
    Photo by Dave Irey
  • The nearly completed frame with engine base/crankshaft and clutch assembly set in place.
    Photo by Dave Irey
  • Straightening a section of brass pipe using a vice and “C”-shaped block for support.
    Photo by Dave Irey
  • The Grasser marine engine’s brass parts laid out for inventory.
    Photo by Dave Irey
  • Ignition timer parts. The arrow points to the new contact that had to be made.
    Photo by Dave Irey
  • Vintage buzz box found at a flea market. The original condenser cartridge had to be replaced.
    Photo by Dave Irey
  • Automotive distributor condenser was used in place of original cartridge condenser in buzz box.
    Photo by Dave Irey
  • The Grasser’s Lunkenheimer mixer.
    Photo by Dave Irey
  • The gas tank and mountings. The tank is from a 1950s lawnmower.
    Photo by Dave Irey
  • The Grasser marine’s cone clutch.
    Photo by Dave Irey
  • The crankshaft, clutch and clutch lever on the wooden frame.
    Photo by Dave Irey
  • Getting ready for the first fire using a 1917 1 hp Alamo as a starter engine.
    Photo by Dave Irey

This is the second in a two-part series on Dave Irey's restoration of a Grasser marine engine. Read Part 1 for the first part of the restoration.

Circa-1907 Grasser Marine

Manufacturer: Grasser Motor Co., Toledo, OH
Serial no.: None marked on engine
Horsepower: 2-1/2-3 hp (est.)
Bore & stroke: 3-1/16 in x 3-1/4 in
Flywheel dia.: 12 in x 2-5/8 in
Ignition: Spark plug w/battery and buzz coil
Governing: Throttle

With the piston, connecting rod and bearings taken care of, it was gasket cutting and assembly time. I purchased a big sheet of 1/32-inch-thick gasket paper at my local auto parts store and cut new gaskets for the crankcase. I also cut out the gasket for the exhaust flange, using exhaust gasket paper.

The rest of the engine connections are pipe thread fittings. I started the reassembly by assembling the piston, wrist pin and connecting rod. New rings went on the new piston and then I installed this assembly into the cylinder, followed by the crankshaft and main bearings. The connecting rod cap with shims was installed and the rod bolts torqued to 45ft/lb. The bottom crankcase cover was then bolted on with the new gaskets, as shown in Figure 1. The crankcase cover doubles as the mount for bolting the engine into a boat frame. As it wasn’t going into a boat, I would have to make a cart.


As I got it, the engine was mounted on a 2 x 8 wood frame. It was cracked, kind of rotten on the bottom edges and generally scruffy. I decided to make a new one from fresh 2 x 12 lumber, with two small 3-inch wheels from an old platform scale on the flywheel end so as to make it easier to move around. The new frame/cart is 33 inches long, 10-3/4 inches wide and 11 inches tall. A long diagonal cut was made across the back of the frame much like the original so the clutch can be clearly seen. To move it around, I made a 5/8-inch-round steel handle and attached it to the back end. It telescopes out of sight into the wooden frame. I also had to make a new pivot for the clutch handle. Figure 2 shows the nearly completed wooden frame.


One of the neat things about marine engines is that they have lots of brass parts. This one has a brass Lunkenheimer fuel mixer, a Tuttle-style timer and a water pump with lots of brass fittings, over 20 pieces in all. All the brass parts on the engine looked very good. Only one piece of pipe was bent and I decided to try and straighten it. To do this, I used a piece of 1-inch-square steel with a “C” cut into one side of it. I then put pipe bushings with hex threads on each end of the pipe. I clamped this into a bench vise to use as a press (see Figure 3) and tightened the vise. The pipe straightened out nicely.