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OHC-230 Tornado Rebuilding Tips
HISTORY: The new 140 HP “Tornado” engine was the most exotic piece of
engineering America had seen in automobiles since the Duesenburg. Some early
alternative cars like the Crosley and Fageol had a similarly designed engine, but
these vehicles had a very short production life. Likewise, the Hall-Scott engine
used in many buses and fire apparatus of this time period had like-built engines.
Interestingly, the Jaguar DOHC-6 in the XKE model was 230.6 cubic inches
@ 265 BHP. The Design for this motor is credited to A.C.Sampietro, Chief
Engineer at Willys Motors, Inc. Mr. Sampietro came to Willys just prior to the
Kaiser Willys merger of 1953. Mr. Sampietro previously worked for Don Healy of
Nash-Healy fame. The ‘block’ design was borrowed from the Continental engine
used in the Checker Taxicab. The bore was increased to 3.34 inches to create
230 cubic inches. The cast-iron cylinder head had staggered valves and only six
lobes on the camshaft – each operating a single intake and exhaust valve.
The OHC-230 Engine was used in the Willys Utility Wagon and Truck
beginning in 1962½ and used again in the Wagoneer, Gladiator, and Truck models
until 1966 when the Buick-designed 225 V-6 Engine was introduced. The (OHC-
230) Engine was used again in the Kaiser M-715 Military Truck and the M-725
Ambulance, although many parts were redesigned and are not interchangeable with
the civilian models.
The OHC-230 Engine was plagued with oil leaks and oil burning complaints.
Numerous service bulletins were issued by Kaiser Jeep Corp.’s Parts and Service
Managers. I will address a few of the most important corrections I have found
in rebuilding these motors:
FRONT MOTOR MOUNT PLATE: The engine is supported on rubber mounts
bolted to this plate. This plate bolts directly to the block with only 3 bolts. It
is then sandwiched behind the aluminum Timing Chain Cover and (attached with
only) a handful of bolts into the fragile front Oil Pan Filler Block. A significant
leak develops as these bolts loosen and the motor mount plate shifts on the block.
It greatly helps to use one of two gasket sealant products when assembling this
piece. Liquid ‘Form-a-Gasket’ by Permatex or ‘Cat’ glue by Caterpillar Tractor
Co. helps bond the gasket and metal together. Do not use Silicone and be sure
to use ‘Fel-Pro’ Thread Sealant on all bolt threads.
CYLINDER HEAD OIL CHANNELS: The casting of the cylinder head around
the camshaft deck is recessed for the oil to flow back to the drain hole at the
rear of the head. This area is rough and partially obstructed near the valve
spring bases as well as the return hole at the rear of the head. With a burr-tip
on a Die Grinder, relieve these areas and smooth-out. This will prevent the oil
from puddling and prevent back-flow. In turn, this will prevent oil leaks around
the valve cover gasket and oil inspiration past the valve stem seals.
VALVE STEM SEALS: A better-designed seal is available, but not usually
included in most gasket sets. The ‘boot’ style should be used, rather than the
‘umbrella’ style. The boot style provides a more positive fit, but may require
machining of the valve stem to install properly.
REAR MAIN OIL SEAL: Be sure to install the rubber oil seal instead of the
rope-type. The aluminum filler block that retains the rubber oil seal is different
from the rope seal. Be sure to balance the flywheel.
MORE RECALL BULLETINS ARE REPRINTED & INCLUDED WITH SERVICE
MANUAL #7.
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