Willys Group Index 10 -01 Engine
Being self dependent I try and do 100% of my own work. But I certainly don’t have an automotive machine shop.
My favorite machinist had been self employed since the late 1950’s and was still going at it a few years ago. But being well into his 70’s I knew his shop time was near an end. So I had 3 final Jeep engines fully machined before he closed up his one man shop for good. Two Dauntless engines for my final Jeeps were machined. But first came this engine which is my final and my best attempt on a Willys F-134 Hurricane. I’ve built a lot of these old L+F 134 engines and truly love their simplicity. But for use in daily drivers it’s clearly well past time to give them up. Yet here I am once again depending on an F-134 for all my travel needs.
10-02 Cylinder Block
By this time the original 1953 engine had undergone one full rebuild in 1983 and had approximately 180K total miles on its two lives. After hard use the block had developed 2 hairline cracks showing up at the typical # 2 + 3 exhaust valve locations. Besides that It previously had a .040 o.s. bore and I prefer not to bore them any further.
So I found me another engine block. The 1963 Hurricane engine I settled on looked solid having no visible defects and upon inspection was expected to clean up with .030 oversized bore.
10-02A Cylinder Head
I hoped to increase the CR as much as possible so I can derive a bit more power from the gasoline. As you know Willys produced an optional high altitude F head for use over 10 K elevation. At the time I could not locate a 7.8/1 compression ratio head. I thought on it a while and decided not to go beyond the optional factory ratio of 7.8/1. Just for starters the block was to be decked and that would shave .010 off the top.
So I settled for the next best thing. I looked over the piles of spare heads that Harry Sheets had in his shed. I picked out a real nice 7.4/1 CR head (intended for use above 8K altitude) and decided to make that one work. After milling the top of block down plus shaving the 7.4 head itself; I ended up with the desired 7.8/1 CR. Add to that a “Best” brand copper head gasket for superior heat transfer away from the valve area.
10-03 Crankshaft
I wanted this engine to be as close to a factory new engine as possible. At the time Matt Fox had a virtually unused crankshaft. The crank was removed from a M38-A1 military salvage wreck with only 50 some actual miles of operation. Well I jumped on that deal and bought the crank with no second thoughts. Took the crank downtown to the best crankshaft specialist in STL. Had him to re-polish all of the dry but rust free journals and so it was essentially as good as new.
10-04 Crankshaft Bearings
So what does one pair with a virtually new crankshaft ? Well at the time it was easy to find OEM standard sized main bearings. Clevite bearings; still in their original Willys boxes. When I installed the crank into the block I test fitted with Plasti-gauge. The Plasti-gauge deformed evenly across the surface right down to the ideal specs.
10-05 Connecting Rods and Bearing
The rods were native to the block and the rod bores were checked for size. Here again standard journal sized OEM Clevites in Willys boxes was the right thing to use.
10-06 Pistons and Pins
A couple years prior I had found a very rare set of .030 oversized OEM Willys pistons for sale. These Willys pistons are special for the F-134 Hurricane as they are heavier built than L-134 Go-Devil pistons. Luckily when the block was miked it looked to need .030 O.S. pistons. So my machinist got the block honed in to a perfect fit. It turns out that the .030 O.S. pistons is the only notable difference between this particular engine and factory new.
10-07 Piston Rings
Here again OEM Muskegon rings; need I say more ? With all ring gaps carefully placed during assembly.
10-08 Valves, Valve Guides and Springs.
Prior to machining the block and head I installed OEM Willys valve guides to proper depth. This block already had the original hard exhaust inserts. Add to that Willy’s boxed genuine Eatonite exhaust valves. And here once again Matt Fox supplied me with a complete set of military surplus NOS valve springs.
10-09 Valve Tappets
This time I did not go new. I fitted all tappets into their original bores and they were snug. So all they needed was a reface the ends on the adjusters.
10-10A Rocker Arm Cover
Over the years Willy’s used 4 differing styles of crankcase ventilation. I decided to built this with what I feel was the latest and most effective system. Unlike the system used in 1953 there is no venting on the rocker cover itself.
10-11 Camshaft and Timing Gears
Here as always OEM NOS including the cam bearings.
10-13 Oil Pump
Here I used an original late design pump as it looked in good order. Simply rebuilt it with a NOS gasket.
10-17 Oil Distribution
Of coarse the complete inside of engine was lubed prior to assembly. The oil gallery including oil filter was primed before its initial start up. Of coarse upon start up the oil pressure comes right up and holds steady as should be expected.
10-18 Crankcase Ventilation
As previously noted a late type crankcase ventilation system was installed exactly as was used on the late type Hurricanes.
10-19 Manifolds
Here I used the original exhaust manifold that was in very good non pitted condition. A good paint and brass stud nuts to make it even better.
10-21 Flywheel and Ring Gear
I used a post 1961 factory drilled flywheel adaptable for either size of clutch cover. Add to that a NOS ring gear. I prefer the original taper type studs for mounting.
10-23 Engine Mountings
Once again OEM NOS rubber mounts.
Lastly;
All engine groupings and any specific parts not mentioned were the carefully refurbished original parts taken from this particular engine.
Stay with me as I continue to detail the complete build via the Willys Group Index.