I have a GMC small block, v8 on my boat. In theory, what would happen if I completely plugged the PCV holes on top of the 2 valve covers? The reason I ask is b/c the black tubes that let this pressure out go straight to my carburator, and its fouling up the air filter after every few weeks because its letting out an oily residue - not too bad, but bad enough to clog the filter and make the carb struggle until i clean it. So what would happen if I plug these tubes instead. BTW, there is no PCV valve so to speak, its only a hollow plastic black tube, going from top of valve cover to carburator.
2007-11-03 13:30:24 · 7 answers · asked by 80's kid 6 in Cars & Transportation ➔ Maintenance & Repairs
You'll blow a gasket in the engine from over pressurizing the crank case and oil will blow out all over the place.
2007-11-03 13:34:43 · answer #1 · answered by Mr. KnowItAll 7 · 2⤊ 0⤋
I don't know much about boats but what i have done on my truck which has a carburated 350 is just pluged the PCV hole going into the carburator and ran the hose coming out of the valve cover somewhere where it won't get dirt or water in it and let it vent into the the air.
2007-11-03 13:58:53 · answer #2 · answered by customcarswy 1 · 0⤊ 0⤋
Sounds like your PVC breather system is restricted. Check the PCV valves to see if they have correct vacuum. Also check the inside of the valve covers to see if the oil is draining down. If the valve cover has the oil filer cap on top, you can remove the oil cap and look in to verify this problem (would look like a bath tub not draining) and the covers will have to be removed to open the drain holes located in the top of the cylinder head.
2007-11-03 13:56:11 · answer #3 · answered by Anonymous · 0⤊ 0⤋
I have noticed some engines with a screen/mess inside the air filter canister ,located where the pcv line enters,before the air filter. this is presumably to help prevent the air filter from plugging off prematurely via the pcv valve
2007-11-03 16:28:08 · answer #4 · answered by trapper1_CA T 5 · 0⤊ 0⤋
Connect the tubes to the inlet manifold AFTER the carby, either that or vent them somewhere (not into a sealed engine compartment) but definately don't block them off.
2007-11-04 00:38:34 · answer #5 · answered by Anonymous · 0⤊ 0⤋
the function of your p.c.v.system is to vent excess pressure from your crankcase.......on older model,s....the vent tube was simply placed downward.....vented to the atmosphere.....since the mid 60,s....it,s been connected to a vacuum port near the carburetor so it can burn these emission,s.......in your case...just vent the tube to a rag or suitable receptacle.......if it,s excessive you may have a little blow by.
2007-11-03 13:57:08 · answer #6 · answered by slipstream 7 · 0⤊ 0⤋
if it's blowing oil out, you need new PCV's
2007-11-03 13:38:56 · answer #7 · answered by Camaro355Z/28 3 · 0⤊ 0⤋