On a d4, What years,series,was the air breather up by the radiator instead of in front of the operator?
Thanks

The air cleaner /oil bath by radiator was on the 4G/7j/2t/5T. sHOULD BE 39 OR 40 TO 50 just guessing but i do know that the air cleaner in front of the operator was a 6u or 7U model Jason

the U series D2, D4 and D6 tractors were introduced in 1947/48 with the D311, D315 and D318 engines. These engines had the cross-flow head with intake on the left side and exhaust on the right. All of these tractors had the air breather in front of the operator.

The earlier tractors used the D3400, D4400 and D4600 engines with both the intake and exhaust manifolds on the right side of the engine and the breather just behind the fan on the right side.

The RD4 was introduced in 1936 and became the D4 in late 1937

Thanks for the information.
Did they again change motors with the 40A tractors and move the air breather back up front?
What were the next ones after the 6 and 7U's through 40A?
Again thank you.

Yes the D315 was dropped after the 6U & 7U & the D330 engine was used, a totally different engine & the first in it,s series with the compact type fuel system. The compact fuel housing is on the right side of the engine where the D315 is on the left & there is no intake manifold as it is built in as part of the head on the left side where the D315 is separate from the head.