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oil from breather
#1
hi guys there is oil coming from my breather cap and i dont know if it's the seals or worn rings
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#2
Normally this condition indicates high crank case pressure. Verify the PCV valve is connected and working properly. If no problems were found there, perform a dry/wet compression test. A dry test should isolate the offending cylinder, then squirt a little oil in to the cylinder and see if it restores the compression reading. If it does, your rings are bad on that cylinder. If the compression is down on most of the cylinders then restored with oil the engine is worn out. Either way a tear down will be required. How many miles on the engine? A cylinder leak down test can be very telling as well as being faster to diagnose the issue if the tool is available. Good luck and keep us informed.

[Image: 16ih3qg.png]
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#3
comanchepilot44;80337 Wrote:Normally this condition indicates high crank case pressure. Verify the PCV valve is connected and working properly. If no problems were found there, perform a dry/wet compression test. A dry test should isolate the offending cylinder, then squirt a little oil in to the cylinder and see if it restores the compression reading. If it does, your rings are bad on that cylinder. If the compression is down on most of the cylinders then restored with oil the engine is worn out. Either way a tear down will be required. How many miles on the engine? A cylinder leak down test can be very telling as well as being faster to diagnose the issue if the tool is available. Good luck and keep us informed.

well i only have the car a couple of months says their is 28400 on the clock but dont know hoe accurate that is
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#4
I'd agree with the above ^. check the pcv system and make sure its working correctly. If the car sat before you got it then it's not unlikely the valve is stuck and crankcase pressure is trying to vent through the breather.
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#5
Pull the breather and see if there is a baffle in the valve cover. Mine did not have them, and it puked out of the breathers. I put baffles in, and it stopped. If there are baffles, then see if it's being pushed out by above normal blowby.

1973 Mach 1 Q code 351 4V, 9A paint, standard interior, 3.50 rear, C6 trans.
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#6
Also make sure that the PCV is pulling from the valve cover and that the opposite valve cover cap is a vented cap. If a PO changed valve covers and didn't use a vented cap it will do as you described.

[Image: 1_01_07_15_8_53_18.png]

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!
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#7
comanchepilot44;80337 Wrote:Normally this condition indicates high crank case pressure. Verify the PCV valve is connected and working properly. If no problems were found there, perform a dry/wet compression test. A dry test should isolate the offending cylinder, then squirt a little oil in to the cylinder and see if it restores the compression reading. If it does, your rings are bad on that cylinder. If the compression is down on most of the cylinders then restored with oil the engine is worn out. Either way a tear down will be required. How many miles on the engine? A cylinder leak down test can be very telling as well as being faster to diagnose the issue if the tool is available. Good luck and keep us informed.

If only one cylinder shows low on dry and normal on wet, you can try soaking in trans fluid for a few days... remove spark plug, pour about a 1/2 cup of trans fluid in and replace plug, after time has eloted remove plug and turn engine over with coil wire off to blow out excess fluid and replace plug and start the engine, recheck compression. sometimes it is just stuck rings from carbon build up, or sitting for a while.

Is there blow by present when you remove the pcv valve?
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#8
Mine was doing the same. It had a loose fitting PCV valve. I put a new grommet around it and it solved the problem.

[Image: 386_07_10_13_5_58_42.jpeg]
My Mustangs:
71 M-code Mach 1, Medium Blue/White Sport, 4R70W, 3L50, Factory Ram Air.
72 Q-code Mach 1, Pewter/Black Sport, 4-spd, 3L25.
65 Convertible, Britney Blue/White/White, more modified than original.
05 Convertible, Legend Lime/Tan/Tan, future classic??
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#9
caspianwendell;80355 Wrote:
comanchepilot44;80337 Wrote:Normally this condition indicates high crank case pressure. Verify the PCV valve is connected and working properly. If no problems were found there, perform a dry/wet compression test. A dry test should isolate the offending cylinder, then squirt a little oil in to the cylinder and see if it restores the compression reading. If it does, your rings are bad on that cylinder. If the compression is down on most of the cylinders then restored with oil the engine is worn out. Either way a tear down will be required. How many miles on the engine? A cylinder leak down test can be very telling as well as being faster to diagnose the issue if the tool is available. Good luck and keep us informed.

If only one cylinder shows low on dry and normal on wet, you can try soaking in trans fluid for a few days... remove spark plug, pour about a 1/2 cup of trans fluid in and replace plug, after time has eloted remove plug and turn engine over with coil wire off to blow out excess fluid and replace plug and start the engine, recheck compression. sometimes it is just stuck rings from carbon build up, or sitting for a while.

Is there blow by present when you remove the pcv valve?
I haven't removed the pcv valve but the car is in the shop getting new brakes and have a new pcv valve bought
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