Crankcase Ventilation System
 

Hey all,

So I am working on swapping my bad 305e with a running 305d in my 65 Suburban (thanks to Rustbucket providing the engine!). I plan to use the heads from my 305e on the 305d since they have recently been rebuilt (maybe they aren't compatible?). The 305d uses the closed type crankcase ventilation system that connects via hose (no flame arrestor though?) to the back of the intake. The 305e uses the filter type canister system and ventilation valves built into the heads under the valve covers.

First, are there pros and/or cons to using either crankcase ventilation system? To use the newer, rebuilt heads, should I swap the filter type canister onto the 305d? How hard is it to pop out the canister and press back into the block?

Maybe I am overthinking this, but I want to make sure I don't screw up crankcase breathing by combining the two. Thanks all! Ken

Re: Crankcase Ventilation System
 

Everything is interchangeable between blocks, you will basically converting the 305D to a 305E. The 305E ventilation system is more efficient with the two PCV valves that are directly mounted to the intake ports.:thumbsup:

Re: Crankcase Ventilation System
 

I have a 305D, and it is set up just like the 305e, the 305 a that I have uses a road tube

Re: Crankcase Ventilation System
 

The 305D use an external PCV valve, 305E will have 2 PCV valves, one mounted on each cylinder head, access to them requires removing each valve cover.

Re: Crankcase Ventilation System
 

Great. Thanks guys. Should I pull the filter canister off of the 305e and put it on the 305d? Or, can I just leave the closed system on the 305d and continue to use it with the new heads with built in PCV valves? I am worried I might damage the filter canister trying to remove it and press it into the 305d block. Thanks!

Re: Crankcase Ventilation System
 

Would like tto know if there are any proven methods for removing the canister, I destroyed one try to get it out for a club member.

Re: Crankcase Ventilation System
 

I was never able to remove mine. I finally went with a suggestion of flushing it with carb cleaner and of course changing the oil afterward. Mine was all clogged with gunk.
You can see the progressing starting around this post in my build thread...http://6066gmcclub.com/showthread.php?p=52791#post52791