Building a Howell V-4 IC engine

Designed engine, drew CAD plans and built first running prototype. Jerry is shown at the left holding the prototype V4, which gives a good idea of its size.

Tom is the museum shop foreman and resident craftsman. He will machine the block, make small fittings and parts as needed and do final assembly.

Tom holds the billet of aluminum that will become the engine block.

The museum's founder, Joe created a machine and a program to grind the camshaft on a specially modified Sherline CNC mill. Joe will be building the crankshaft for the V-4.

Joe is shown making helical distributor gears for the Seal project.

Project: Four aluminum pistons plus a fifth for a spare.

Project: Engine/Radiator Mounting Skid Rails

Project: Air Cleaner

Project: Fan blade programming and cutting

Project: Assorted tools and fixtures

Craig maintains the web site, takes the photos for this page to document the project and is coordinating the program and keeping the builders and public informed on progress.

Ya gotta start somewhere... Here is the block of 7075 aluminum Pam cut out on Sherline's FlowJet water jet cutter. A US Quarter shows size. It will become the engine block of the V-4. Tom is seen holding it here in hopes we will soon be able to take a similar shot of him holding the completed block and eventually the completed engine.

The billet of material has been squared up to size and is shown in the first photo bolted to a fixture on a faceplate while the crankshaft hole is bored. The second photo shows the other side of the block after the flange on the second side has been turned and the two internal counter-bores have been added.

2. The cylinder holes on the first side are drilled to make a clearance hole for the boring tool.

2. Both cylinder holes on the first bank are completed. The scribed line in the red Dychem shows where the second face will be machined for cylinders 3 and 4.

2. A boring bar is used in the mill to open up the cylinder holes to exact size.

The block with all 4 cylinders bored.

The block is mounted to a large faceplate on the lathe and a dial indicator is used to find the center of the cylinder holes. The second photo shows the block removed from the faceplate after each cylinder hole has been counter-bored.

The bottom of the block as of late November shows the access to the crankcase. At this point about half of the original material has been removed.

This setup on the Sherline mill was used to open up the five lightening holes called for in the intermediate cam gear. The holes were first drilled and then (as seen in the photo) a 3/8" end mill was used to true them up. The plans for the part can be seen in the background.

3. A different angle of view for the above process.

From the bottom side you can see tow pairs of holes for the valves and the spark plug holes nestled between them.

This setup shows the radius on the end of the rocker arm brackets being cut using the rotary table. Note the special clamp Tom made to hold the brackets during machining.

The finished rocker arm brackets. After machining, a couple of passes on a stone or piece of fine sandpaper on a flat surface remove the machining marks and allow the part to transition smoothly from flat sides into the radius.

One of the heads with rocker arm brackets and spark plugs installed.

Bob Seigelkoff made these four aluminum pistons plus a spare.

Tom Boyer machines a round boss on the distributor drive housing/camshaft end cover using a rotary table on the museum shop's Sherline Model 2000 mill.

The finished distributor drive housing (L) and camshaft end cover is shown before and after it is split. The two halves will be installed separately side-by-side on the finished engine using two common bolts in the center.

The distributor spark advance arm was milled from a solid piece of brass. The curve in the upright portion was done using the rotary table.

The brass distributor housing was completed and the spark advance arm seen above is now attached with two small screws.

The completed distributor and drive unit is shown assembled and disassembled.

The body of the brass oil pump inlet elbow is being milled to the 1/8" OD using the rotary table.

Two different views show the completed oil pump inlet elbow. Though small, this part required a number of different machining operations. The finished elbow is smaller than a dime.

The timing gears are complete thanks to some help from Fred Smittle. They were made utilizing a Sherline mill and P/N 8700 CNC rotary indexer.

The front face of the block has been relieved, leaving an oval boss. The front cover exactly matches this shape and also has a raised circular area that fits into a matching countersunk area of the block in front of the main bearing. The second photo shows the cover in place but not bolted on. These operations required several different setups on the rotary table to cut the oval shapes. So you beginning machinists won't feel bad, Tom had about four hours of machining in the cover the other day and stopped to take some video of the curve being cut on the rotary table. Distracted by trying to shoot video while making the cut he turned the handwheel the wrong way, scrapping out the part. We won't be showing that video...

Tom snapped the left-hand photo while the block was still mounted to the Bridgdeport mill table. The sides of the block are shown being milled away, removing the hold-down fixture holes used earlier and finally leaving the classic "V" shape profile. The second photo shows the block after it was removed from the mill and the sharp corners were broken slightly with a file. The raw block of 7075 aluminum started out at a weight of 6.32 pounds. At this point it now ways just 1.42 pounds. Almost 5 pounds of metal has been removed by the many machining processes over the past seven months. With this many hours of work invested in one part, each operation is approached with great care, as Tom would definitely not want to have to start over now. Refer back to the earlier photo taken on 9/19/07 of Tom holding the raw billet block to see how far it's come.

Meanwhile, Tom has been working on the eight aluminum rocker arms and they are completed too. The last photo shows the fixture Tom used in the rotary table to machine the outer shape of the rocker arms with their rounded ends.

Progress on the block continues. Shown also are some of the many fixtures Tom has had to make to complete parts and operations.

Today's mail brought Adam Krichbaum's CNC machined and polished rails that the engine and radiator will eventually rest on. Nice job.

Tom has been working on the radiator for a couple of weeks. The tedious part is making the eight brass, finned rods out of square bar stock. Many grooves are cut using the parting tool and then a hole is drilled down the middle from each end. A top and bottom tank are then made to connect all eight finned rods. Aluminum side pieces bolt to the top and bottom tanks to act as a support. Photos show the fins being cut on a Sherline lathe, the assembled eight finned rods with bottom tank, the top tank and the full assembly placed on a set of plans.

The final assembly shows the aluminum side supports bolted in place. The radiator assembly is now almost ready for soldering to seal it.

The radiator lower mounting brackets were fabricated and the radiator can now be bolted onto the frame rails.

The connecting rods were just completed, and Tom's photos are shown here. They are a split base type rod because the V-4 arrangement of this engine has the two banks of pistons directly opposite each other as on a double V-twin motorcycle arrangement. Because the crankshaft is built up inside the case, the bases of the rods do not need to be split and bolted back together. Bronze bushings will be pressed in to provide a wear surface.

(Photo 1) The aluminum connecting rods now have their bronze bushings turned and pressed in. (Photo 2) Tom is  turning the four steel piston sleeves that will be secured in the block using O-rings. The closest cylinder hole in the block has a sleeve in place, while the other sleeve is displayed outside the block. A US Quarter is used for size reference.

Bronze valve guides have been machined for the block and head--8 each plus a spare. The plans actually call for the pushrod guides in the block to be square, but they were easier to make round, and that's the way they are on Jerry's prototype, so Tom made them that way too.

The built-up crankshaft is now in progress. The flywheel, collet, pulley and nut are shown assembled in the first photo with the other three pieces of the crank laid out behind it. The second photo shows all the parts separate. The crank elements will need to be machined to shape and drilled, and the pins that connect them must be turned to complete the crank.

The crankshaft counterweights have now been fully machined and it is shown ready for installation in the engine block. The second photo shows the crankshaft center bearing holder installed in the block. The final photo shows the crank installed in the block yesterday as a test, and it spins "smooth as butter," as they say.

The completed carburetor is shown by itself and with the air cleaner made by Dave Eggert installed.

Photo 1 shows the rocker arms with the rocker arm pins and ball bearings installed. Photo 2 shows the valves with the valve spring retainers ready to go.

4. The intake manifold casting was machined to fit and bolted in place between the heads. Here it is seen with the carburetor and air cleaner unit installed on top and one of the pushrods in place through the bronze guide.

Tom has finished the components of the oil pump. The gear teeth were cut from cold-rolled gear stock. The pump halves are assembled with four small socket head screws.

The pump was tested and run in by powering it with the Sherline lathe for a few hours. The intake hose is in the foreground. Coming from the left side of the pump itself is a stream of oil created by the interlocking pump gears.

The aluminum oil galley is shown with its brass plug. On the right is the galley installed between the block and oil pump.

Joe Martin is seen here setting up and using the Sherline cam grinder to finish the two overhead camshafts on Howell V8. Computer controlled axes move the camshaft back and forth and rotate it while the spinning grinding wheel takes them down to size and shape one pass at a time. Jerry's plans call for individual cam lobes to be glued onto the camshaft blank, but we decided to grind them in one piece. The next step will be to case harden the camshafts, which Tom will do in the museum shop.

The two finished, ground camshafts were completed on the Sherline CNC cam grinder. Sherline is considering making a limited production run of this machine. Anyone interested?

Pam Weiss programmed the fan blade profile into Sherline's Flo-Jet water jet cutter and cut five blades from a sheet of brass, leaving only a few small tabs to retain them in the sheet. Tom then cut the tabs and filed the blades to shape before putting the required foil curve into each blade using the fixture shown at the left. The first photo shows the straight blade before the vise is closed, and the second shows the curved blade after the vise was tightened.

The blades were glued and pinned into slots on the fan hub. The final photo shows the fan in place on the engine along with the pulleys.

Here is a detail of the fan pulley on its shaft before the fan was attached. The second photo shows the crankshaft pulley.

The oil pump pulley, collet and nut are shown as built and installed along with the other pulleys.

Larry Simon has been working on tooling for the engine. They are, starting at the top and going clockwise is the Piston Installing Tool, Cam Setting Tool, Flywheel Puller, Cam Positioning Sleeve, Cam Gear Setting Tool and Piston Ring Thinning Holder.

Tom has turned the 8 valve lifters and 4 wrist pins.

The cylinder liners were installed and the connecting rods installed on the crankshaft and connected to the pistons to make sure everything was in alignment. There are no rings on the pistons yet, so it turns over easily, but it did give Tom some relief knowing that everything lines up and works smoothly when the crankshaft rotates.

This shot is of the water pump parts. Starting at the 12 o'clock position and going clockwise: Main housing, water outlet, cover and pulley assembly consisting of the pulley, 5 rare earth magnets and 2 ball bearings and the black plastic cover. On the bottom is the mounting bracket followed by the impeller assembly consisting of the impeller, shaft and 5 rare earth magnets, and finally the water inlet. In the center above the dime is the cutwater. The magnets in the pulley drive the impeller by magnetic attraction, thereby eliminating the need for a shaft seal. (See Jerry Howell's drawing.)