The Stovebolt Site Forums The Shop Area Engine Shop Adding a PCV valve

Awkward? So what was your "handle"?

Tim's (tclederman) site is a great resource

http://www.1954advance-design.com/

I have it bookmarked for quick reference.

The PCV orifice diameter is the key part you need to look after. To small and it never sucks out enough condensation, to large and it affects performance (you really are simply creating a vacuum leak after the carb).

I'm sure 'close' is good enough. But most of my manuals that deal with trucks that come with and without PCV included the PCV orifice as a source of poor idle/performance.

If your motor is blowing by that bad, fix it.

This photo:

http://s142.photobucket.com/user/551stsuburban/media/1955%201st%206400/005_zps3d5a38e6.jpg.html

Shows the PCV valve just after the brass 90deg fitting. Of all the bits and pieces I have when I bought my truck motors I have a draft tube and air cleaner with PCV fittings.

I did read this from the 57 Truck manual in the specifications page:

CRANKCASE VENTILATION
Positive crankcase ventilation on forward control models... vacuum operated closed outlet tube from ventilator body to inlet manifold provides suction when engine is running.
Road draft ventilation on all others.

Looks good but where is it drawing air into the crankcase?
Need a vented cap unless there is a clean air source I don't see.

Update. Heres a pic of the PCV mounted in the road draft tube. It is still a temp setup so don't mind my little rigged up strap to hold the PCV into the grommet.
I figure the gorilla glue will eventually let loose and when it does I have a 30.08mm freeze plug that I will drive into the road draft tube w/a proper grommet that will hold the PCV. Until then this works

I went w/a PV1053 PCV is is the straight eqivilent to the 90 degree angled PV 141. The straight PCV lined up better.

The larger PCV that I tried and didn't work was the PV233. It is all metal and also straight but came w/a 90 degree adaptor. IT would stay in the glued in grommet without my rigged up strap but unfortunately is too large and draws too much vaccum which negatively effected the vaccum windshield wipers.
Dave

You need to have the proper air cleaner with the PCV hose connection. Its just in the manual that only COE's had PCV setups... regular cabs still used the draft tube.

For some reason its really hard to find a picture of an original COE w/motor... but I really didn't put much effort into it.

My 53 6400 firetruck has a PCV valve on it. The truck is origial with 11,000 miles on it. I got it from the original owner/department. It is not a COE. I can take pictures this weekend if anyone is interested in seeing the setup-

http://chevy.oldcarmanualproject.com/parts/1929_54/134.htm

List 'Ventilator unit - positive ventilation' and it says it comes with instructions... perhaps a dealer option?

I'm gonna guess that 'positive ventilation' is what we are calling the PCV setup?

Pics of old trucks are always welcome!

What year (or, years) are you referring to "only COEs had PCV setups"?

Resurrecting an old thread...

Does anyone know what the part number is for the factory PCV Valve? I have the 261 with the PCV setup that plumbs over the top of the valve cover to the intake manifold.

What year?

1948-1957 is shown here.

My 261 is a 1955-1958 model. I have the tube and the line that runs over the top of the valve cover and fits into the fitting on the intake manifold. All fits well, but the PCV valve is stuck and not able to be fixed.

This old thread has some part nos:
PCV Valve