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crank case venting question

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Old 01-05-04, 07:57 PM
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crank case venting question

hey carl, can i put the 2 crank case vent hoses to a T adapter then to the hardline on the firewall, ive got my ratsnest removed on the 79 and im still getting lung butter

im going to be rebuilding my 83-85 carb soon and putting that on the 79 manifold
cause the 79 carb is alot different than the 83-85

anyway just wondering if i can do that with the crank case hoses for proper venting

thanks

-greg
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Old 01-05-04, 08:11 PM
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Hey Gregs,

Can you tell me how did you remove the rats nest? Like, how the vacuum line should go on a 79?

Sorry for being off the subject in your thread.

Thanks,
Nelson
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Old 01-06-04, 08:13 AM
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Greg, you need some sort of PCV setup to pull out the junk from the case. My suggestion is to run it like the tutorial says, or use a PCV valve like peejay does.
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Old 01-06-04, 03:42 PM
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I ran a hose from the carbon canister in my aircleaner lid to one of the nipples on the oil filler tube, teed the tank purge line in to that line, and put a little oil breather filter on the other filler tube nipple. Works like a charm. That and the line for the vacuum advance are the only rubber vacuum hoses on the motor.
This is on an '80.
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Old 01-06-04, 05:59 PM
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I removed ALL vac lines and emissions junk, I'm going to run SU carbs, run a catch-can, and lock the dizzy - less to go wrong!
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Old 01-06-04, 06:07 PM
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You need to maintain a tank purge line and some means to vent crankcase gases.
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Old 01-07-04, 12:36 AM
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Just run a small breather on the neck.
I run a vented catch can connected to the neck, and blocked off the other vent on the block.

Works fine.

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Old 01-07-04, 12:42 AM
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DF can you get some more detaild pics and instructions?
thanks man
BTW your engine bay gives me wood
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Old 01-07-04, 12:51 AM
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Originally posted by Gregs
DF can you get some more detaild pics and instructions?
thanks man
BTW your engine bay gives me wood
I'll post some tomorrow. It looks nice and simple now, and works great. But This old setup gives me Wood.



Oh well. Later this year I suppose..
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Old 01-07-04, 01:00 AM
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This good enough? Or Do you need better pics?


Last edited by Directfreak; 01-07-04 at 01:05 AM.
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Old 01-07-04, 01:16 AM
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very very nice
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Old 01-07-04, 03:27 AM
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Originally posted by rotarydankus again
very very nice
so when is that going to be functional, dankus? keep the pics coming...
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Old 01-07-04, 07:18 AM
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Originally posted by Gregs
DF can you get some more detaild pics and instructions?
thanks man
BTW your engine bay gives me wood

Originally posted by Directfreak
I'll post some tomorrow. It looks nice and simple now, and works great. But This old setup gives me Wood.



Oh well. Later this year I suppose..
Dankus...

Notice how when someone's stroking Directfreaks prickly *****, he utters not a word about grammer?
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Old 01-07-04, 07:22 AM
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Originally posted by Directfreak
Just run a small breather on the neck.
I run a vented catch can connected to the neck, and blocked off the other vent on the block.

Works fine.

Do you suppose boost has anything to do with why you apparently don't need any suction to remove the emulsified steam that forms in the crank?
I've heard of others doing this with results, but only rarely, and had not made the relationship until just now.
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Old 01-07-04, 08:54 AM
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Originally posted by Sterling
Dankus...

Notice how when someone's stroking Directfreaks prickly *****, he utters not a word about grammer?
LOL. Gud kech, sTerling.

I'm not sure I understand your comment about boost being related to the icky emulsified crap. Can you explain?

DF, what's that breather mounted on?

Edit: Duh, it's a catch can. WTF is a catch can?
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Old 01-07-04, 09:13 AM
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Originally posted by Sterling
Do you suppose boost has anything to do with why you apparently don't need any suction to remove the emulsified steam that forms in the crank?
I've heard of others doing this with results, but only rarely, and had not made the relationship until just now.
Sterling:
You know, that is a very good question. I don't know the answer. Maybe the 2nd Gen guys might now, since they deal with both N/A and Turbo applications in the same type of car all the time.

Slashdawg:
It is a vented catch can from Jaz Products.


I got mine in clear so I can see when it has oil within it.
Here is a site with some details.
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Old 01-07-04, 10:43 AM
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Well it just seems that no matter how how I run mine, without a PCV valve to allow that **** to be sucked out into the carb as "oiled water vapor", it just stays in there and condenses in the steel tube.
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Old 01-07-04, 12:06 PM
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Thanks for the info and link DF.
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Old 01-07-04, 01:32 PM
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Originally posted by Sterling
Well it just seems that no matter how how I run mine, without a PCV valve to allow that **** to be sucked out into the carb as "oiled water vapor", it just stays in there and condenses in the steel tube.
That's been my experience also.

I was thinking the same thing about the boost affecting the way the crankcase gases vent, and it seems like there would have to be considerable blowby for any appreciable pressurization to occur. If in fact that is what's happening. Good question, though.
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Old 01-07-04, 01:42 PM
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posted by me
...now matter hoh how I run...
-I meant "hot".

It would be interesting to have a pressure gauge hooked up to the crank in both an NA and a boosted rotary just to see.
(I do not know what damage sealing the crank would do.)
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Old 01-07-04, 03:10 PM
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Originally posted by Wankelguy
That's been my experience also.

I was thinking the same thing about the boost affecting the way the crankcase gases vent, and it seems like there would have to be considerable blowby for any appreciable pressurization to occur. If in fact that is what's happening. Good question, though.
If blowby increased enough to cause the increased pressurization, wouldn't that cause other problems? Like increased oil consumption?
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Old 01-07-04, 03:13 PM
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Yeah most people I know just leave the line on the oil filler open. I've got the vent line on my block running to the charcoal canaster then back to the gastank.

For the line on my oil filler tube, do you guys thing I should leave it alone, get a breather filter on there, or plug it up?
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