2.0 Crank & Head Venting Issues |
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2.0 Crank & Head Venting Issues |
tjtryon |
Oct 17 2016, 03:56 PM
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#1
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Newbie Group: Members Posts: 20 Joined: 15-June 16 From: Indianapolis Member No.: 20,112 Region Association: None |
Car: 1973 2.0 with dual Webbers
Issue: I have a leak from the drivers side valve cover, and poking around, I know my crank & head venting is not correct, which may be what's causing issues. I wanted to fix this first, before I change the valve cover gasket. I have what I believe is the CB breather box already on the car. It has a hose connected to the oil filler area, one to the fan shroud, and one that is venting to atmosphere. I have a hose port at the base of the carb intake manifold on both sides, that does seem to vent air out. I assume these are the head or valve cover vents, but am not sure. Additionally, nothing in the system seems to pull vaccuum, unless the fan shroud vent does so. I have 3 main questions: What are the hose ports at the base of the carb intakes (front of intake on drivers side, rear of intake on passengers side)? What's the correct routing of the hoses? Where does the system pull a vaccuum? Many thanks in advance! |
HAM Inc |
Oct 18 2016, 06:32 AM
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#2
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
Plug the vents from the heads. You don't want them as they will allow oil to accumulate in the valve covers rather than drain back quickly to the crankcase. This leads to lower oil pressure, especially during spirited driving.
You only need one line (1/2" is plenty for a street engine) to breath the engine, and it's best if it comes from the oil filler area. You do not want to run a line from the fan shroud to the breather can. Many people route a hose from the top of the breather can to the aircleaner. This has pro's and con's. Pro's; less mess in the engine bay from the vapors. Con's; the vapors, if excessive, can gum up the carbs and intake ports. Len Hoffman |
falcor75 |
Oct 18 2016, 10:59 PM
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#3
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Senior Member Group: Members Posts: 1,579 Joined: 22-November 12 From: Sweden Member No.: 15,176 Region Association: Scandinavia |
Plug the vents from the heads. You don't want them as they will allow oil to accumulate in the valve covers rather than drain back quickly to the crankcase. This leads to lower oil pressure, especially during spirited driving. You only need one line (1/2" is plenty for a street engine) to breath the engine, and it's best if it comes from the oil filler area. You do not want to run a line from the fan shroud to the breather can. Many people route a hose from the top of the breather can to the aircleaner. This has pro's and con's. Pro's; less mess in the engine bay from the vapors. Con's; the vapors, if excessive, can gum up the carbs and intake ports. Len Hoffman Hi Len. I read your and Jakes research about plugging the head vents last year and figured I'd follow that advice for my stock 2.0 with EFI. While I'm not certain it was the only cause I think it may have contributed to my engine puking oil from the passenger side valve cover all over the dyno when I took it to get tuned. (the port on the oil filler tower was connected to the driver side ITB setup.) |
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