Production Time Line
Notable changes to the Pearson 10M over the production run from 1973 to 1981
Chain Plates
In the original design the 10M had the primary chain plates anchored to a knee about 6" aft of the main bulkhead. At some point in the first half of the production run Pearson made a change to the chain plate configuration. They removed the knee and replaced it with an aluminum I-beam unit to transfer the chain plate loads to the main bulkhead. The forward lowers still connect to a knee about 12" ahead of the main bulkhead. This change occurred sometime after hull 101 in 1975. For boats built before the change Pearson basically issued a recall authorizing owners to have re-enforcing added to the knee. There was apparently some deformation of the hull from the chain plate loads. The recall letter describes the deformation as cosmetic and not a structural problem. The original owner of 1974 10M #86 reported that he experienced a chainplate failure on the boat. The boat was repaired by the dealer at Pearson's expense. The owner was told his was the last 10M to be recalled for repair. Since hull 101 does not have the I-beam chainplate mount I think Pearson applied the reinforcing called for in the recall as the boats were built to the hulls after 86 and up to the first I-beam boat.

Engines
The 10M came with several different engine installations. Most seem to be powered by the Atomic Four gas engine with a direct drive transmission. According to the BUC price guide diesels were optional with a Faryman 25hp in 75 (I have seen a '74 with this engine), a Westerbeake 20hp diesel in 76. the Faryman again in 77, and a Volvo 23hp (MD11) from 78-80. The volvo MD11 in my 78 10M has a v-drive transmission with the output shaft of the engine facing forward and the prop (left handed) located about 3 feet forward of the rudder skeg. The Atomic 4 and the Faryman I saw have the output shaft facing aft and the prop was about 1 foot in front of the skeg.

Rig
The standard 10M rig has a jib hoist of 44 feet. There was a tall rig available with a jib hoist of 46 feet. I don't know what model years the tall rig was available but I think it was 1975 to 1978. The total sail area of the standard rig is 524 sqft, the tall rig is 549 sqft. I have been told 12-14 tall rig 10M's were made, there are three on my owners list. I think more then 14 were made.

10M 229 (one of the last made) has painted spars. The spars on my 10M are anodized.