Check with your local welding shop , we found a cold weld compound at a welding supply, we had a Dozer with a cracked radiator tube, I used the same process to repair the damaged tube and within 24 hours it was and still is running , the labor to repair the machine was over $5000 ,the construction company had a deadline and a week of down time was out of the question . I have used regular J.B. Weld in a high heat area without issues, I wont use J.B quick for a high heat area, I personally would try the regular J.B. weld in your case, I have used regular J.B to repair a damaged 3208 Caterpillar block deck at the fire ring area ,the repair lasted me over 6 months while being driven700 plus miles in a week till the new replacement truck arrived, I Designed an injection tool to force the compound into the crack and then built up the deck surface around the top of the cylinder fire ring area, I have used Marinetex on lower water jacket cracks (low heat area) and none have failed. Mabe you can find a sample size from the manufacture or a dealer, check with a caterpillar dealership ,some mechanic may have a bit left over from a previous repair ?
