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! |
tjtryon |
Oct 19 2016, 02:46 PM
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#2
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Newbie Group: Members Posts: 20 Joined: 15-June 16 From: Indianapolis Member No.: 20,112 Region Association: None |
OK, GregAmy and Ham say to plug the 45° ports at the base of the carbs, and Falcor said it was a factor in making his engine puke from the valve cover. I have new (cork) valve cover gaskets (Felpro) to put on the engine, which looks like a 10 minute job (I'm sure it's not though), so hopefully, between that, and getting proper venting to the engine, mine will stop puking oil.
Replacing gasket looks to be: 1) Remove spring clip 2) Pull valve cover 3) Remove old gasket 4) Clean both mating surfaces 5) Put new gasket on cover 6) Mount cover on head 7) Return spring clip Can I use grease to hold gasket on valve cover, or do I need to use something stronger like an RTV? Anything I missed above? If not, it looks to be a 10 minute job. Afterwards, I need to: 1) Cap both valve cover/head vents 2) Only have host from filler cap area to breather box 3) From there, I can run a draft line from breater to vent to atmosphere below the car, vent to carb, or vent to a K&N filter. I assume venting to carb is more environmental, venting to a little K&N filter will cause a fine oily mess in the engine compartment, and venting to atmosphere would be bad, environmentally, but would be fairly simple, and provide a slight amount of vacuum to the system. Thoughts, suggestions or advice on what will make this simpler to complete this evening would be greatly appreciated! |
GregAmy |
Oct 20 2016, 10:23 AM
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#3
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Advanced Member Group: Members Posts: 2,311 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
OK, GregAmy and Ham say to plug the 45° ports at the base of the carbs... Negative, Ghost Rider. The Tangerine kit takes hoses off each head (to properly vent the top ends) as well as a hose off the port next to the oil fill, and runs them to the container. From the bottom of that container is a drain hose that is plumbed to a fitting at the base of the oil fill box. I decisively suggest you vent both heads and block to that container. |
barefoot |
Oct 20 2016, 10:56 AM
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#4
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Senior Member Group: Members Posts: 1,279 Joined: 19-March 13 From: Charleston SC Member No.: 15,673 Region Association: South East States |
OK, GregAmy and Ham say to plug the 45° ports at the base of the carbs... Negative, Ghost Rider. The Tangerine kit takes hoses off each head (to properly vent the top ends) as well as a hose off the port next to the oil fill, and runs them to the container. From the bottom of that container is a drain hose that is plumbed to a fitting at the base of the oil fill box. I decisively suggest you vent both heads and block to that container. OK, now I'm confused. You say vent the heads to the breather can, but HAM says plug the head vents. Does it have to do with the type of vent can design used ??? Barefoot |
GregAmy |
Oct 20 2016, 02:01 PM
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#5
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Advanced Member Group: Members Posts: 2,311 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
You say vent the heads to the breather can, but HAM says plug the head vents. Does it have to do with the type of vent can design used ??? No idea why someone is recommending you not use factory breather ports. Is it because their vent/can design does not allow oil to be separated and flow back into the engine? For example, my current design on the race car is just three 1/2" hoses going into a quart container, with a manual drain on the bottom. I collect 1/2 pint or so of liquid oil in there each day (couple session of hard running). I see no problem with that, it's part of the design. Mine is a brandy new Tangerine build with one track day and one race weekend on it. However, if this were my street car I'd likely be really annoyed at having to keep track of that can and ensure I empty it regularly so it does not overflow and/or I do not run low on oil (even though I'm running a 10-qt dry sump system so that's unlikely). I will be installing the Tangerine design, which includes a can that accepts hoses from all three places (both heads and the fill vent) with internal baffling to separate the liquid oil, condense the vaporized oil, and return the resulting liquid back into the crankcase through a fourth fitting added to the fill box. That, in my opinion, is the "correct" way to do it. |
HAM Inc |
Oct 20 2016, 02:11 PM
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#6
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
You say vent the heads to the breather can, but HAM says plug the head vents. Does it have to do with the type of vent can design used ??? No idea why someone is recommending you not use factory breather ports. Is it because their vent/can design does not allow oil to be separated and flow back into the engine? For example, my current design on the race car is just three 1/2" hoses going into a quart container, with a manual drain on the bottom. I collect 1/2 pint or so of liquid oil in there each day (couple session of hard running). I see no problem with that, it's part of the design. Mine is a brandy new Tangerine build with one track day and one race weekend on it. However, if this were my street car I'd likely be really annoyed at having to keep track of that can and ensure I empty it regularly so it does not overflow and/or I do not run low on oil (even though I'm running a 10-qt dry sump system so that's unlikely). I will be installing the Tangerine design, which includes a can that accepts hoses from all three places (both heads and the fill vent) with internal baffling to separate the liquid oil, condense the vaporized oil, and return the resulting liquid back into the crankcase through a fourth fitting added to the fill box. That, in my opinion, is the "correct" way to do it. I'm not interested in rehashing this subject, but I will set the record straight that I don't sell breather cans. |
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