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Holly carb sucking oil

Twin 86 454's FWC. The stb

Twin 86 454's FWC. The stbd Holly carb has oil hanging on the bottom of the flame arrestor. Is it possible that the vacum is sucking it from the hoses that are connected from valve covers??? (Each valve cover has a hose leading to a "T" then leads to the flame arrestor.) Port engine bone dry with same set up. Could I be having a Carb problem with excessive vacum? Any thing over 2200 rpms and the engine flutters after running for about an hour which I assume is related. Any solutions on this? I am looking forward to the day when I can open the fridge more than the engine hatches.
 
"A couple of things come to mi

"A couple of things come to mind on this issue. Yes, very likely related to blowby, and not related to excess vacuum.
I don't understand the "T" comment. You should have one, 5/8" hose from each valve cover and they EACH go to the outside of the flame arrestor.
Internally, the valve cover area is subject to oil misting, and a significant blowby will tend to blow out oil. You can move to a breather cap with the internal mesh to catch the oil mist. This will help even with strong blowby. They can be had either "twist in" or "push on" styles. About 3" in diameter or so, and with a grommet and barb to accept the 5/8" hose."
 
An 86 with a Holley....sounds

An 86 with a Holley....sounds like a mod.

Are the rocker covers stock or aftermarket?
 
Diver Dave...On my "T"

Diver Dave...On my "T" comment; I have a breather tube from each valve cover (stock covers btw)that lead to a three way tube in the shape of the letter "T". Since the flame arrestor only has one breather tube fitting...I used that connection so that B-tubes can connect to the flame arrestor. The old style flame arrestors had two attachements (one for each cover) the new ones do not. (2-yr old Hollys) So the opinion is excessive blowby...and a compression test will confirm this?
 
If the baffles are still in th

If the baffles are still in the covers then blowby is a good candidate. Do the compression test dry & wet.
 
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