The Stovebolt Site Forums The Parking Lot '60-'66 Trucks 283 v8 Valve covers / Breather holes / PCV ???

Hello... I seem to always have questions I don't quite know how to ask or where to begin so here goes..

My 1960 C10 283 v8 has aftermarket cheapo chrome valve covers (VC's). The passenger side VC has 2 holes (one is plugged with a cap and the other has a breather with a tube) and the driver side VC has only a breather cap. The oil fill tube in the front also has a breather cap (3 breathers). I found while looking for original chevy valve covers for a 1960 v8, that original orange Chevrolet VC's have no holes in them for breathers at all.

What's the science of "no breathers in valve covers" vs. "breathers in valve covers" and what is best for the 1960 283 v8?

I also just received a road draft tube conversion kit to replace the draft tube (lower driver side near the oil filter) with a pcv that vents into the rear plug in the back of the rochester 2 Jet carb. (is that right?)

Question 1... If I leave a breather cap on only the front oil filler tube will I have enough air through so i can I cap the holes in the VC'c, or replace the VC's them with stock "no-hole" vc's?

Question 2... Once I hook up the pcv conversion kit, should I leave the breather with the tube in the passenger side VC rear hole, hook a hose to it, and "T" it into the rear of the carb also?

Question 3... What is the ideal way to plumb this so i don't blow up my crankcase, blow a seal or gasket, or catch fire and still maintain the correct oil pressure?

Please any help sorting this out will be greatly appreciated.

Thanks in advance.
Q

the covers with holes are from newer engines that had tubes from them to the air cleaner and a solid cap on one for oil filling [no tube at the front] - there would have been no valve cover holes on an original 283, and there could have been an optional pcv valve from the factory - the road draft tube is replaced with a domed plug that has a fitting for the rubber hose to the pcv valve at the carb base [not actually into the carb, but into the manifold] - no problems with that configuration as long as you check/clean the pcv regularly .... you'll find info on the original style valve in sect.8 of the shop manual

re-reading your missive, I think you may not be aware there was originally a road draft tube at the back of the block behind the distributor, which is where the pcv ties into, NOT into a valve cover

Bill

Thank you Bill, This all helps clear up the mystery... So the Draft Tube attaches behind the distributor and drops down the side near the Oil Filter. That will be fun to get to!
Thanks again.
Q

Actually the road draft tube dropped down on the passenger side as seen in the image:

[IMG]http://img718.imageshack.us/img718/1170/283g.jpg[/IMG]

It is easy to access, being on top of the block right behind the intake manifold. It attaches with a long bolt right through the top. One of the bellhousing bolts captures a tab near the middle of the tube to keep it in place.

The concept of the road draft system was that while the vehicle is in motion air flowing over the bottom of the tube would create a draft drawing crankcase fumes out of the engine. The failing in the design is that if the vehicle idles a lot, or drives at very low speeds (like a milk truck) a sufficient draft was not generated to clear the fumes. The result was that early engines with this system were frequently packed with sludge so thick it could plug up the engine.

In the mid 60’s before the grommet was adopted for the pcv valve, early pcv installations used a metal adapter that attached with a bolt through the top just like the draft tube, but they had a hose nipple for connecting the smog valve.

none of my spare engines here have the original road draft still on, but I put up a picture of the OEM pcv setup so you can see what you need - I suspect yours may have already been modified there

Bill

Thanks again Bill... I would assume I can get to it without pulling the distributor or motor!! Sounds like a serious tuneup will be required after the conversion. Any Idea how to make the mixture more lean or less rich on a rochester 2 jet? I see there are only "idle mixture" screws?
Thanks
Q