Trivea

[Nelson]

What modification was made to the R3 breather system in order to pass New York pollution standards?

[Dwight FitzSimons]

There are two kinds of "tubes" that attach to the right side of the oil pan, one capped off with an open breather cap, the other with a male fitting (3/4"?) for a hose to attach to.  That hose would feed into the intake system somewhere.

--Dwight

[Nelson]

That’s true, Dwight. What I was referring to was the valve cover breathers.

[Dwight FitzSimons]

On 9/6/2022 at 10:42 AM, Nelson said:

That’s true, Dwight. What I was referring to was the valve cover breathers.

Oh, so it must be open versus closed breather caps.

--Dwight

Edited September 13, 2022 by Dwight FitzSimons

[Nelson]

22 hours ago, Dwight FitzSimons said:

Oh, so it must be open versus closed breather caps.

--Dwight

 Correct. The small holes around the bottom of the breathers were silver soldered shut. Sort of odd when it could still vent around the clearance between the breather tube and the breather.

[Dwight FitzSimons]

4 hours ago, Nelson said:

 Correct. The small holes around the bottom of the breathers were silver soldered shut. Sort of odd when it could still vent around the clearance between the breather tube and the breather.

In theory I assume a PCV system would draw some (metered) air into the rocker covers through the breather caps in order to help the engine pull crankcase fumes into the intake to be burned.  But, in reality, with the loose clearances in an R3/R4 fumes might be pushed out through the breathers.

--Dwight

[mfg]

Very interesting topic!