View Full Version : D333 identification

03-04-2019, 10:40 PM
Is there a way to ID a D333 without a serial number? I have a 977h with a D333 but it looks like the engine may have been swapped at some point and the serial number tag on it had the serial number removed. It still has the 53a part on there, just not the rest of the numbers. I want to make sure Im ordering the right parts for it when I do order them. Is there a way to tell whether it has a 4.5 bore or 4.75 without taking off the heads?

03-05-2019, 04:08 AM
Look at the side of the block. If you can see the individual cylinders in the casting it is the big bore. Small bore is straight across.
To others correct?

03-05-2019, 05:11 AM
I don't think that is correct. The D330 and the D333 blocks were all cast with indentations between the cylinders, but they were both 4.5" bore for about 10 years of production. In the early 1970's the bore was increased to 4.75" along with some other changes and the engines designated the D330C and the D333C.

I think you could go by the block casting/part numbers to make sure what you have, but the best way will be to wait until you strip it down so you can measure the cylinder bores.

Old Magnet
03-05-2019, 09:16 AM
The 53A's all used the D333A 4-1/2" bore engine.
Look at the rocker arm cover, it will be the low height 6 bolts down the center version.
Water pump will be belt drive, the later D333C's are gear driven.

03-05-2019, 09:12 PM
Thanks, I remember seeing 6 bolts down the middle of the rocker and Im pretty sure it had a belt driven water pump so 4.5 bore it must be. Ive got to drive back out to it when I get some parts to show up and will double check, still working on getting it home.

03-06-2019, 04:05 AM
As OM says, the 4.5" bore D333B engine had an alloy rocker cover with six bolts down the middle, the 4.75" bore. introduced in 1968, had a deep pressed steel cover with bolts all the way round its mounting flange. To be sure you have a block suitable for a turbo you need to see serial number prefix 53A or 74A, 75A, 82A or 83A on the block, the are a couple more which carried a turbo, mainly the early rigid 966 and the 966B.

Old Magnet
03-06-2019, 10:35 AM
No such thing as a D333B vehicle engine. The only D333B designations are the 79Bxxxx Industrial engine and the 80Bxxxx Marine engine in either turbo or turbo and aftercooler form. These are 4-1/2" bore and have gear driven water pumps unlike the belt drive of the D333A's. Exception being the 78Bxxxx 1673B truck engine. turbocharged and aftercooled.
If anyone can show otherwise I'd like to see the info source.

03-06-2019, 08:49 PM
I have a d333a on a gen set and the water pump is gear drove, looks like cat couldn't make up it mind what to build...WA7OPY

Old Magnet
03-06-2019, 09:33 PM
The gear drive water pumps provided an attachment drive for auxiliary water pumps, hydraulic pumps and air compressors, items that could not be accommodated by v-belt drive alone.