1936 Engine Differences

Unknown

I have heard that the 1936 Hudson and/or Terraplane engines (6 cylinder) are a one year engine. I know the distributor is on the side, rather than on the rear top. What exactly are the differences between a 1936 and a 1937-1947? Also the Terraplane head is marked Terraplane...is there an internal difference between it and a head for a Hudson? Thanks For any help.

Jon B

As far as I know the Terraplane and Hudson engines are essentially the same. Of course in 1937 (and later years I'd guess) Terraplane offered either a single or a dual throat carb (the intake manifolds would have been different too). The Hudson Six would have had the dual throat carb (this carb carried through to 1947 with minor changes).



I think the valve stems got smaller in 1938.



All 6-cyl. engines had the distributors down on the passenger's side up to 1940 or 41 (I'm hazy on the exact year), when it moved to the top of the engine at the back. Here it stayed until the last year for the '3x5' six, 1947.



I'm guessing that the 1936-7 engines were identical except for the option of the dual-throat carb in 1937. However, there well may be some difference in the accessories like carb, generator, etc., and possibly the valve stem sizes.

Park_W

Jon pretty much has it. The distributor went to the rear for '40. Biggest difference from '36 to the '37-'39s was that in '37 they did go to the 2-barrel carb for the deluxe model Terraplanes, and the exhaust manifold on all '37 engines was enlarged a bit for better breathing. As Jon said, the valve stems were smaller diameter (Terraplanes and Hudsons) starting with '38. Hudson Six and Terraplane engines for '36 were basically the same, except for the cylinder head markings. There may have been some small differences in standard compression ratio between the two, but I don't think so. Optional higher compression heads were offered for the Terraplanes as well as the Hudsons.

Geoff

The '36 engine was indeed a "one-off". It had the same small exhaust ports as the '34-'35, but had the water pump mounted on the block instead of the head, and the head was the first "flat" design. So it is in fact a transition stage between the two designs. It uses the same head gasket, inlet and exhaust maniolds as the earlier engines, but the water jacket and pump are the same as the '37 onwards. Valves are 3/8" stems, same as '37. Carb is single throat. Crank, pistons, rods, etc are all the same from '34-'47, except the cam was changed in '41 to accommodate the top mounted distributor, with a worm machined into the rear journal and shimless rods were used from '38 onwards. The horsepower was slightly up from '35, to 92 in standard form. I think that about covers the differences. You can easily identify a '36 block, as it has round exhaust ports instead of oval like the '37 and later, and the head studs are all the same length. Earlier engines had longer studs in the centre row.

You can use a later head and gasket to give slightly higher compression.

Geoff.