Thread: Another Parts Number Question with apologies

Firstly, I do apologise for so many questions. I certainly have more to learn than most here, and I really appreciate your generosity and help. .

I have another parts number question, as I am trying hard to get to the bottom of the convoluted history of my engine.

My vehicle is a 1953 Series 1 80" which was originally fitted with a 2 litre Siamese-bore motor. Around 1955 the block was replaced by Land Rover using a later 2 litre Spread-bore block with many of the parts from the original motor being reused wherever possible. So I knew I had a motor of mixed "heritage" but as I started to make my list of restoration parts, I found even more anomalies.

The Connecting Rods are cast with part number 238142, which I believe is not a Land Rover part number at all, but is from a Rover P4, so apparently they used whatever was at hand. My pistons seem to be correct for the 2 litre, but wear a part number of 59 240575 1c, which I cannot find any reference to at all on the internet.

So when I went to order Con Rod Big End Bearings, I found that my engine is fitted with bearings marked with PV or VP 2726 0.30. Unfortunately that is neither a Land Rover nor Rover P4 part number. So with Con Rods that may or may not be the same as Land Rover 2 litre rods, can I safely order +0.03 bearing for a 53 2 litre motor and expect them to fit?

Any thoughts or advice would be greatly appreciated.

regards and thanks
Jeff

Originally Posted by jedwards

Firstly, I do apologise for so many questions. I certainly have more to learn than most here, and I really appreciate your generosity and help. .

I have another parts number question, as I am trying hard to get to the bottom of the convoluted history of my engine.

My vehicle is a 1953 Series 1 80" which was originally fitted with a 2 litre Siamese-bore motor. Around 1955 the block was replaced by Land Rover using a later 2 litre Spread-bore block with many of the parts from the original motor being reused wherever possible. So I knew I had a motor of mixed "heritage" but as I started to make my list of restoration parts, I found even more anomalies.

The Connecting Rods are cast with part number 238142, which I believe is not a Land Rover part number at all, but is from a Rover P4, so apparently they used whatever was at hand. My pistons seem to be correct for the 2 litre, but wear a part number of 59 240575 1c, which I cannot find any reference to at all on the internet.

So when I went to order Con Rod Big End Bearings, I found that my engine is fitted with bearings marked with PV or VP 2726 0.30. Unfortunately that is neither a Land Rover nor Rover P4 part number. So with Con Rods that may or may not be the same as Land Rover 2 litre rods, can I safely order +0.03 bearing for a 53 2 litre motor and expect them to fit?

Any thoughts or advice would be greatly appreciated.

regards and thanks
Jeff

Jeff,
Because your piston pins are the smaller 17.47 mm size, you need the bearings for the 52/53 engine. The numbers on the parts are often the casting or makers reference numbers, not the Rover number. There is more to just fitting the bearings and tightening the nuts. They are a selective fit. The initial nip or crush is important. (See #4291 workshop manual) Have you measured your crank pins to see if they have been reground to .030" undersize? Until you measure all the re- sizeable parts, you are in the dark. The Rover motor is not as easy to rebuild as a modern engine as they were designed to be hand assembled by an experienced fitter. Not overley complicated, but they do require an understanding of 1930's engine design, part clearances and assembly methods. The super tight tolerances we expect today were not as readily available and very expensive, hence the rquirement of a lot of hand fitting, because skilled labour was a lot less costly than buying super expensive high precision production machinery of the time. They did not have access to the CNC machines of today.
You are going to need someone with this sort of background looking over your shoulder to avoid an expensive mistake. Have you rebuilt many engines previously? If not, this could be a bit of a worry for you as this engine is at the steeper end of the learning curve. Ask around at the local vintage car club or mens shed. There might be a retired old school mechanic in one of them. Not much point talking to any of the younger mechanics, unless they own an old Land Rover!
Don't get discouraged! Keep asking questions. 5380.