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Tube from CCV to Intake

BBeach

NAXJA Forum User
Location
Worcester
I couldn't find anything on this but I remember seeing someone who replaced the plastic line that goes from the front CCV to the intake (airbox for stock). I used some cheap caliper at CAP and it was 14mm and 16mm so basically 5/8 and 9/16. However all they had was heater hose and I've heard that it was bad to use that because the hot oil vapors damage the hose. Does anyone know where to go to get the right kind or would heat hose do good for a while?
 
NAPA had the hose assemply that goes from the front of the valve cover to the plastic joint for $21 and the plastic joint to air cleaner for $18. The small hose assembly that goes from the back of the valve cover to the intake was only $9.

Sure was easy.....

Bob
 
Well they sell the PCV line for $1/foot at auto zone and CAP but not in 5/8". I was gonna get 5/8" and then for the 9/16" end just use a hose clamp. Im not looking for a direct replacement but rather a more flexible longer "line".
 
BBeach said:
Anyone know if heater hose will work, or just do the pcv stuff?

I've got a rebuilt motor in my jeep with only 12k on it, and I've used a heater hose (I forget the size) on the front of the valve cover with no problems.

The front hose going from your valve cover to the air filter is for air to come into your valve cover to replace the fumes that were sucked out by the rear vacuum line going from your valve cover to the intake manifold. That's how it is designed, but it doesn't always work that way. If you have no piston or valve blowby, and if your rear vacuum line isn't plugged up, you'll definitely have no problems with the heater hose. It will just be carrying clean air from your air cleaner to inside your valve cover.

But ... if your motor is really old, and you have the blowby and/or plugged vacuum line, you'll likely see oil in your air box. In that case, pressure has built up in your motor, and it is spewing oil and fumes through that front hose into your airbox to relieve the pressure.

I'm not sure how well heater hose can stand oil and fumes. When I was a dumb teenager, I used heater hose to hook up an external oil cooler to an ancient VW motor that was running hot. The hoses became very flexible when hot, but never failed.

Overall, I think you'd be just fine with the heater hose. Just make sure you don't have oil in your air filter. If you do, you have a more serious problem to take care of.
 
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Yeah I just bought 2 feet of heater hose, drove maybe 100 miles and no problems. Out of curiousity, its not hard to change those PCV valves, I havent changed them since I got the jeep and it prolly cant hurt to do so if they're cheap enough.
 
BBeach said:
Out of curiousity, its not hard to change those PCV valves, I havent changed them since I got the jeep and it prolly cant hurt to do so if they're cheap enough.

Well, the elbows coming out of the valve cover are easy to replace ... but they aren't any sort of valve. They are just straight elbows. I wouldn't replace one unless it's cracked. If you have any leaks around the elbows, you can replace the gaskets only.

Underneath those elbows is something inside the valve cover that I think is some sort of oil deflection screen. I'm not sure. You take off the valve cover, turn it upside down, and look inside. You'll see each of the two openings is covered with something held by two screws. When I replaced my motor, I reused the old valve cover and didn't take those things off while I was cleaning it. I wish now that I did ... just to be thorough and make sure it's clean in there.
 
Yeah I took one off a 99 4.0 before and its just a straight through kinda thing, not sure where I got valve in there...but mine leaks a little around the little rubber gasket. Im pretty sure I can just buy that by itself at auto zone or something. It sure looks better with a hose too.
 
montanaman said:
Well, the elbows coming out of the valve cover are easy to replace ... but they aren't any sort of valve. They are just straight elbows. I wouldn't replace one unless it's cracked. If you have any leaks around the elbows, you can replace the gaskets only.

Underneath those elbows is something inside the valve cover that I think is some sort of oil deflection screen. I'm not sure. You take off the valve cover, turn it upside down, and look inside. You'll see each of the two openings is covered with something held by two screws. When I replaced my motor, I reused the old valve cover and didn't take those things off while I was cleaning it. I wish now that I did ... just to be thorough and make sure it's clean in there.

I took them (the oil deflelction screen somethings you mentioned) apart on my valve cover, cleaned them and reused them. They are a sort of reed valve system like they use in air compressors. A thin flexible sheet steel flapper over a flate plate, probably designed to allow air flow in just one direction. Still not sure I reasembled mine correctly. They are designed to stop oil from getting out.

Now that I think about it they should be set up in reverse order, one as an inlet the other as an outlet valve. I do know they needed cleaning BADLY on mine at 225,000 miles! They were stuck open with sludge!:eek:. I am afraid I reinstalled mine as both inlets or both outlets. I had not paid enough attention to how they went together when I took them apart.:doh:

I think I am going to look into replacing them on mine along with a better valve cover gasket. I am not liking the Cork gasket I used 12 months ago.
 
Ecomike said:
I took them (the oil deflelction screen somethings you mentioned) apart on my valve cover, cleaned them and reused them. They are a sort of reed valve system like they use in air compressors. A thin flexible sheet steel flapper over a flate plate, probably designed to allow air flow in just one direction. Still not sure I reasembled mine correctly. They are designed to stop oil from getting out.

Now that I think about it they should be set up in reverse order, one as an inlet the other as an outlet valve. I do know they needed cleaning BADLY on mine at 225,000 miles! They were stuck open with sludge!:eek:. I am afraid I reinstalled mine as both inlets or both outlets. I had not paid enough attention to how they went together when I took them apart.:doh:

I think I am going to look into replacing them on mine along with a better valve cover gasket. I am not liking the Cork gasket I used 12 months ago.
I'm in the same situation as you ... I used cork gasket and don't really like it ... at some point, I'm going to take off the valve cover and reinstall it with no gasket ... just ATV compound and clean the reed valves.
 
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