3204 Long Blocks Reman Technical Supplement Caterpillar

3204 Long Blocks

Long Block Selection: General Information

Long blocks are not available for every engine application. The long blocks we do offer can, however, be used to service many applications even though the long block does not exactly match the original engine configuration. When the consist of the Reman product offering differs from the consist of a customer's engine, only the dealer and customer can decide whether or not it makes economic sense to change the parts that differ.

It's Caterpillar's policy to incorporate the latest critical engineering changes into Cat Reman products. Therefore, long blocks may be offered with some parts from a later design era as service repairs for engines from an earlier design era. An example is the 3406C crankshaft, connecting rods, and pistons which are in certain 3406B long blocks. The result is that the parts in the long blocks match each other but do not match the parts consist of new production engines, nor do they match any single Parts Book. When long block parts consists differ from the official parts list, Reman provides an engine plate alerting the customer to Special Instruction or Service Magazine articles for information on non-standard parts.

Make sure any future engine/long block repairs which do not use parts called for by the original Parts Book, or official replacements called for by parts and service sources, are carefully documented. If you choose to make any configuration or consist changes, good documentation can prevent problems the next time parts are ordered.

3204 Long Block Selection

First, use normal parts information sources (parts books, microfiche, SIS, NPR, the Reman Products Guide, etc.) to look up the Reman short block intended to service the customer's engine arrangement. Next, find that short block in the following "consists" chart and read the long block part number from the top of the same column.

Next, follow the long block candidate column down into the consist section of the chart. Check the camshaft, then cylinder head part numbers shown against the part numbers called for by normal parts information sources to service the customer's engine. Don't forget to check the NPR to determine that you are using the most current part number. Now check the other part numbers listed in the same column of the consist chart. For a long block candidate to become a "selection", all the part numbers listed under the long block part number should match the correct service part numbers for the customer's engine. You may select a long block which isn't a perfect match if you believe changing the parts which don't match is worth the time and money to do the work.

Use the Correct Oil Pump

In some cases, changing the oil pump may be required. When a 3204 long block without piston cooling jets is used as a service repair for an engine with cooling jets, a different oil pump is called for. Be sure to read the Service Magazine articles referenced at the bottom of the following "Consist and Selection" chart.

Some Disassembly may be Required

3204 long blocks are shipped with the valve train fully installed and adjusted at the factory to ensure all valve train parts will function properly. The engine front plate is not included. When the camshaft gear is pressed on, the camshaft must be removed from the long block before the customer's original front plate can be installed. This will require resetting the valves upon reassembly.

Lifting eyes and a valve cover (with gasket) are installed for shipping purposes. If these parts do not match the parts from the customer's engine, the customer's parts must be transferred to the long block. Any parts removed from the long block must be returned with the engine core. Add charges will be assessed for any missing parts.

* - Current blocks are not interchangeable with early parts. See: "Changes to 3204 Engine Accessory Drive and Engine Block; New Engine Arrangements Used" Service Magazine (October4, 1982).
** - Piston Cooling Jets. See: "New Pistons Used" and "Cooling Jets Removed and Different Oil Pump Used" Service Magazine (February 9, 1987).
# - With wide valve train gears. Requires current front cover, implement pump gear & spacer, and Tach. drive Gp. See: "Improved Engine Timing Gear Train" (for 943 & 953 Loaders). Service Magazine (October 4, 1982).
@ - Use the one that fits. One of these new oil cooler cores (in addition to the customer's old oil cooler core) must be returned with the engine core.