3j,5j cylinder heads

[rjh-md]

We aquired an early 3J,5J cyulinder head recently, part number 5B596 which changes to 7B3060 for all later heads . All the later heads have a allen head support bolt that comes into the side of the head ,and touches the injection chambers .
My question is ,was there a problem with the eariler 5B596 heads with out this support bolt ? Possibly a vibration problem ,losening the chambers ,or viberation problem causing the upper chamber seals to leak in time ?
Can we use this eariler head ,as its just a show tractor without problems?

[Old Magnet]

On the early heads the whole injector and pre-combustion chamber assembly was held down by clamps and bolts. Later heads had screw in chambers and the set screw was provided to lock them in place. Can't tell you for sure about interchange but except for the different injector arrangement I suspect they will.

[rjh-md]

This eariler 5b596 head has screw in chambers also ,and look just like the chambers used in all the later heads,7B3060
the only difference appears to be that there are no allen head bolts going threw the water jackets like on the 7B3060 head with a seal around the head on the outside to seal the bolt, which touches or locks the chambers after they are screwed in the head
I wondered why this was added to all later heads ,unless there was a problem with the eariler heada and chambers ?

[Old Magnet]

Part of the evolution I'd guess. Screw locks came in with screw in chambers but there may have been some transition.

Can you tell if the heads might have been modified?

[rjh-md]

the eariler 5B596 looks orginal .the later 7B3060 casting looks the same as the 5B596 ,except for the allen set bolts and drilled and taped holes in the side of the head ,and of course part number up dated to 7B3060 ,and this number lasted threw out later produced tractors in both the 3J,and 5J according to my parts books
I am having this eariler head rebuilt ,and will chance it ,this machine will never do any real work
Thanks for your input Old Magnet