The Stovebolt Site Forums The Shop Area General Truck Talk Removing Road Draft Tube On 235

I know you guys said you didn't want to modify it... So I'm just adding this comment for whomever else happens by-

The original Road Draft Tube had some fiber in the 'body' of it to filter incoming stuff and condense the outgoing stuff- Rumor has it that it was horsehair. Problem is that over the years it has probably disappeared. I think steel or brass wool might work as a substitute.

Lots of people add a PCV valve to their Road Draft Tube, or replace it. There are a couple of ways I've seen it done-

One way is to do it like it was done on the later engines, with the PCV valve on the road draft tube body. To do it you'd cut the draft tube off the body that sticks into the engine and weld a freeze plug into the hole. Before you weld in the freeze plug you drill a hole in it and weld on a bolt with threads that match a threaded PCV valve. Then you run a vaccum line from the other side of the PCV valve to the intake, which might require the use of a Tee if you have vaccuum wipers.

Another way is to get rid of the draft tube and buy and aftermarket push in valve cover breather with a hose outlet. The you'd use a tee on the intake that you could thread a PCV valve into and then run a vaccum line between the two.

Why convert to a PCV valve? Less oil under your truck, more negative pressure in the crank case to help not blow out the gaskets? Might be more fuel efficient...