Serial Number Location on 3406

The 3406 engine in my truck had the number on a plate glued to the valve cover, I have no idea if they stamped the number on the block anywhere. If you have twin engines, the number from the outside engine should work, the parts should be the same for both. You MAY need the arrangement number also.

George

If it isn,t on the valve cover then Cat engines would have it riveted on a little plate on the left side of the block most times just below the head toward the rear but a few engines I,ve seen them farther up toward the front.

Something I found out many years ago when I was dealing with corrosion with stainless bolts and steel bolts in aluminum, stainless and cast iron was to use a dab of silicone gasket maker on the bolts, studs and nuts when assembling. It worked so well that I now do this as a matter of course. Not only do things come apart as easily as they went together, the silicone sealant works as a thread locker. No more broken bolts, and no more vibration taking things apart before I'm ready to take 'em apart either.

I never heard of using the gasket maker but at the dealer we always used the never seize wherever we needed to use it. Yes steel & aluminum don,t get along together so that is a must to coat the whole bolt if it passes through the aluminum or threads into it.One other place that I always coated the bolts was on the D343 & D346 engines where the valve cover bolts went through the aluminum spacer between the cover & head.Some of the OTR truck engines have alum. bell housings & related parts so they need the never-seize on the bolts too.Other places that you must put the seize on is the pre-combustion chamber threads & around the exhaust manifold bolts & nuts & glow plugs too if so equipped.The Cat # for the 4oz. can is 4C5598 but they have larger cans too.I even used to coat some gaskets in different places so they wouldn,t stick the next time you disassembled it.

Sincerest thanks for all the replies. Some people have a fear of little balls/springs popping out when a cover is removed, I just know that at least one bolt will twist off on whatever I happen to touch.
The unit is located on the main deck of the tender, about 6-8 feet above the water line, so it gets lots of spray.
Somewhere, there is a record of all the components installed when this unit was built, but given the way drilling rigs move around the world, it would not be easy to track it down. The unit came up here from Angola for a 2 or 3 well project, which is why I am on it, and the rumours have it either going to Thailand, or back to Angola after this project is complete.
It remains to be seen if the department manager will send a mechanic up to sort this out. Since the contract has the customer paying cost plus for airfare and a day rate, maybe the mechanic will come up, and he can make a day trip into town if he needs any parts. There are Caterpillar dealers in Africa, but I do not know about the parts supply.