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C4 transmission fluid coming out breather line

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Old 06-24-2014, 11:17 PM
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bradleyb
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Default C4 transmission fluid coming out breather line

Hi

I have a 66 mustang coupe with a C4 transmission with transgo shift kit, 302 engine, Edelbrock intake with Holly street avenger carb.

My problem is that I noticed transmission fluid shooting out of the breather line onto the intake in the back of the engine - when I measure using the dipstick at running temp, the fluid level looks ok. It also shifts and runs ok. Why is the fluid coming out of the open breather line (goes from vacuum modulator through hose and hard line to top of engine compartment in the back)???

Thanks in advance for your input!

Bradley
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Old 06-25-2014, 06:19 AM
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Boogie's_AutoRama
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The only way I figure trans fluid can get into the intake system is thru the vacuum modulator.
Vacuum mod must be leaking fluid.







.
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Old 07-18-2014, 10:00 PM
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bradleyb
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I have a rubber line that goes to a hard metal line that leads to the top of the engine compartment - I thought it was a breather line but fluid is coming up through that.

Would the vacuum modulator cause that?
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Old 07-19-2014, 12:44 AM
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rmodel65
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the vacuum modulator is on the trans. if the diaphragm ruptures you can suck transmission fluid thru the line
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Old 07-22-2014, 10:19 PM
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bradleyb
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If it ruptures will it still run properly? Mine runs great
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Old 08-02-2014, 02:39 AM
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bradleyb
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rmodel, do you think it would suck the fluid from the transmission up the metal line to the top of the engine compartment?
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Old 08-02-2014, 08:19 AM
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rmodel65
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yes you would have an active leak+vacuum= atf being sucked into the engine
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