what is this hose for...and why is it peeing oil ?

[diymirage]

on the left hand side there is a breather (right?) the larger hose goes into the air cleaner
the smaller one hooks up to a small diameter tube that runs along the firewall underneath the car
this seems to be the cause (or better said, the place) of my oil leak

i had another breather from a 360 but it only had the larger nipple on it so for the time being i put that breather on and capped the smaller hose

where does it go ?


and what could cause this to leak ?

(i first suspected a bad PCV valve so i replaced it and that didnt fix it)

 

[TrailBeast]

You mean this one?
If so I would have to say the PCV may not be keeping up with the engine blowby so it's venting oil out the small hose.
Might want to clean or replace the PCV valve and see if it clears up.
Can you feel obvious vacuum at the PCV valve?

 

[diymirage]

that is the one im talking about

i did replace the PCV valve and it didnt really help

should i feel vacuum at the valve?
i thought that was a one way valve to let air out rather then in so i should feel pressure rather then vacuum ?

but, i shall check and see what i find

 

[TylerW]

The small line connected to the crankcase breather is the vapor line from the fuel tank. '70 and '71's routed it into the crankcase breather.

You should NOT have oil coming out of that line or the crankcase breather at all. Air goes in the crankcase breather, get's fumed up and gets sucked back out the PCV valve and burned.

You could check the line and the port at the carb to see if it's plugged up, but if not that's a classic sign of way too much blowby. What do you hear and see coming out of the oil cap if you remove it with the engine idling?

 

[nm9stheham]

You could check the line and the port at the carb to see if it's plugged up, but if not that's a classic sign of way too much blowby. What do you hear and see coming out of the oil cap if you remove it with the engine idling?

Yes do this and see if there is vacuum on the PCV; you would remove the PCV from the valve cover with the engine running and the PCV sitll connected to it's hose and there should be vacuum on the open end of the PCV (that you pulled from the valve cover). If no vacuum, follow the hose the carb base area and see where it is plugged.

 

[TrailBeast]

Thanks guy's.
I was away for a bit (like usual)

 

[diymirage]

thanks for the advice guys
i will check the vacuum and report back when i find out what is going on


on an unrelated note, i will be replacing this engine with a V8 soon, i take it i should route the fuel tank evap line (is that the correct term?) back into the same system no?

 

[TylerW]

Yes. Remember those breathers are cleanable with solvent, drying and then re-oiling. You can't buy the special 2-port version at anymore.

















Also maybe some semi-gloss black paint

 

[1970Dart198]

diymirage, if you plan to do a V8 swap, I would recommend keeping your early version of ECS. Does your gas tank have the 4 hoses on the driver's side of the tank? If so, plumbing off the line will not be very good. A good locking pressure-release cap will do you fine if you do want to block it off. But valuable fuel vapors will be escaping into the air.

See that hose that runs from the top of your your carburetor bowl to your fuel pump? That is also part of the ECS system and routes fuel vapors back into the crankcase to be re-burned in the PCV system.

If you do want to do a V8 swap, check out the factory service manual for your car and see how the V8's were hooked up. I know their breather caps had 3 nipples on them instead of the slant's two. One hose in the V8 version went to the 3rd nipple.

Good luck!