1969 340 is down

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Bennoel 10 said:
Long story short I acquired a 69 340 swinger that has a rebuilt engine. Everything was fine until I hear a noise similar to a flywheel/ring gear hitting the inspection cover. Noise lasted about 5 seconds give or take. After the initial noise stopped I realized lost of power. My destination was 3/4 mile away so I proceeded. After removing the spark plugs and doing a compression test one cylinder was zero, #3 I believe (second from the front, pass side). Removed the value covers and low and behold the rockers appear to be out of place. (See pictures). Anyway I'm pulling the engine and going from there. Just wondering what the membership has to advise. Thanks in advance.

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Photos 3 and 4 indicate the pushrods on different cylinders rubbing on the pushrod holes in the head. Rockers must be in the wrong location. Unfortunately this could be expensive.
 
Dale Davies said:
Photos 3 and 4 indicate the pushrods on different cylinders rubbing on the pushrod holes in the head. Rockers must be in the wrong location. Unfortunately this could be expensive.
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I agree. Can't get my head around why they got it right on one side and not the other, kinda like two different people working on the rebuild. Number #3 cylinder intake rocker doesn't move at all nor can it be moved and I can see through a bore scope something shiney (value) on top of piston. Just hope the block can be saved.
 
Does it have the rocker arm spacers the ones under the shaft bolts in the wrong place they are different with or is it a big block rocker mixed in with smaller block
 
Both rockers on #3 cylinder are installed wrong. The pushrod cup offset should be away from each other.
 
pt70 said:
As viewed from your first picture: There are 2 different stamped rocker arms, a left and a right. They should an L or an R stamped on them. For EACH cylinder, L is on the left and R is on the right. They are not related to intake/exhaust valves.

The notches on the rocker arm shafts are on the left sides of the heads pointed downward [toward the cam]. The rocker arm shaft washers are correctly placed.

The scraping of the pushrod on the cylinder head is a giant clue. I would pull the heads and check things before I pulled the motor.
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No L or R on any of the rockers. Checked the rockers on another 340 engine and it has the R & L on the rockers.
 
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