What might cause a vibration or miss in a 259 / 289 v-08 in a pickup that has been rebuilt with all parts new except the camshaft. The vibration can be felt in both the cab and steering wheel. A new second 259 engine was put in the pickup with a new clutch and flywheel but the vibration was still in the truck?
1. The engine mounts can cause this type problem if they
are installed without the steel Sleeves on the bolts, because the
bolts can be over tightened which will squash the rubber portion
of the mounts and the vibration will be transferred to the frame.
Also check external parts like the exhaust pipe or clutch linkage
rubbing on the frame.
2. Loosen (or remove) the fan belt and run the engine to
see if the vibration goes away with the water pump and generator /
alternator not rotating.
3. A bad distributor or carburetor can cause a vibration.
4. Check the spark plug wire routing: When you route the
wires on the left side, do not run #5 and #7 together or a spark
may be induced in #7 when #5 fires. That can cause the incoming
charge in #7 to ignite early. The 259 and 289 v-8's both have a
firing order of 1-8-4-3-6-5-7-2 with the cylinders numbered from
the front of the engine left side (drivers side) 1, 3, 5, 7 and
right side 2. 4. 6. 8. As you can see the firing order will fire
#5 then #7 and that is the reason for the special routing of the
#5 and #7 ignition wires.
5. Make sure the valves are not too tight. Set the intake
to .025 and the exhaust to .027, I do not prefer setting them with
the engine idling.
6. Slightly retarded cam or ignition timing will not induce
a vibration, although advanced ignition timing might. After the
valves are adjusted the compression should be checked to be sure
all cylinders are reasonably equal and then check the timing to
insure it is set to IGN with the engine warm and at idle: 500 RPM
7. Check the vibration dampener on the front of the crankshaft to make sure it is not installed backwards. The holes are offset to prevent this, but they aren't offset so much that a person couldn't distort the rubber cushions and install it backwards. The engine mounts on trucks hold the engines more firmly than passenger cars, so use dodge pickup truck mounts they can be adapted to the Studebakers and give the truck a little smoother feel.8. Don't forget to check the front axle conecting rods for wear. Slao don't forget to check the tires for balance. This item is because the vibration can be felt in the steering wheel.