PCV doesn't seal to manifold. . .how do I fix it?

[Zero Signal]

I went to change the PCV valve the other day and noticed that there is a gap between the outside edge of the valve and the intake manifold so it can't make any vacuum. It also has oil all around the opening where the valve goes. The valve works fine, in fact it seems to be better than the Fram one I bought to replace it so I'm gonna keep it.

Has anyone else noticed this? I though I had a vacuum leak and I think this might be the problem. Now I'm trying to figure out a solution.

 

[95CobraMike]

can you buy a new rubber gromet? i have seen them at auto zone before...i think for $4 if not i know they have them at a ford dealer for about $10


would that fix it?

 

[SeventyMach1]

Is the gap you're talking about between the valve and the grommet...... or between the grommet and the intake?

If it's between the valve and grommet.... I'd just clean all of the oil out of it and see if the valve has a tight fit. If not, just get a new grommet.

 

[HISSIN50]

John, in this heat I would strongly suggest getting a new grommet, screen and motorcraft valve. Aftermarket valves tend to not fit too tight.

on both stangs, the grommet was totally vulcanized - new ones are so supple compared. I had to use silicone spray to get the valve into the grommet - it was that tight.

LRS sells the 3 pieces for cheaper (even with shipping) than the dealer probably (unless you have a hook up).

Good luck bud.

 

[RIO5.0]

the grommet was totally vulcanized - new ones are so supple compared. I had to use silicone spray to get the valve into the grommet - it was that tight.

Wow..Good point...mines slides in like butter...maybe its spent, I'm sure it is...Who is LRS ??? Got a link...

 

[Zero Signal]

Well I just picked up the vatozone special for $3. I'll try to get it in before work in the morning and see if it sits right and seals with the valve. Like I said, the stock valve is working perfectly, so it's staying. Besides I don't feel like replacing that hose that goes to it since its super brittle but still good.

I hate working there, it's a pain having to do all that with one hand.

 

[18mustangs]

Wow..Good point...mines slides in like butter...maybe its spent, I'm sure it is...Who is LRS ??? Got a link...

LRS is Late Model Restoration in Waco, TX. Their website is 50resto.com and they have good prices.
Tim

 

[RIO5.0]

Thanks Tim....

 

[HISSIN50]

Yeppers about LRS (Andy, we know you knew that).

John, I used a grommet from Checker in the 88 vert and it sealed fine. It was a Motormite IIRC. The factory grommet is about as cheap from LRS, which is why I suggested it. You should be good to go.

FWIW, some guys RTV their valves into the grommet. That does not sit well with me.

I wondered if that line to the PCV valve was really molded or just as hard as a rock. I removed it when I did the air/oil separator (motivated by Andy. ) and I was afraid to drop the hose.

 

[RIO5.0]

I went to Napa and got 3' of 3/8" fuel line hose and swapped all the PCV stuff for under 3.00, I needed that much for the oil separator lines...2' would do the stock PCV set-up...Rock hard hoses are not a good thing...
Hose is cheap money..

You can replace every vaccum hose for under 10.00 just buying it by the foot...then ya got no worries on vac leaks... I can see John's point though, one handed working the PCV hoses would be a pain...

 

[legalize420]

I went to Napa and got 3' of 3/8" fuel line hose and swapped all the PCV stuff for under 3.00, I needed that much for the oil separator lines...2' would do the stock PCV set-up...Rock hard hoses are not a good thing...
Hose is cheap money..

You can replace every vaccum hose for under 10.00 just buying it by the foot...then ya got no worries on vac leaks... I can see John's point though, one handed working the PCV hoses would be a pain...

thats what i did. ford wanted like 28 bux for the hose assembely and they did not even have it in stock. 3/8 fuel line and a new tee will do the trick. i got my screen gromet and valve from 50resto.

 

[CManT1914]

LRS is Late Model Restoration in Waco, TX. Their website is 50resto.com and they have good prices.
Tim

Actuallly they are in Hewitt. Used to have a g/f there.

 

[extremetrek]

Maybe this a stupid question but what kind of problems might a loose fitting grommet cause?

 

[HISSIN50]

Maybe this a stupid question but what kind of problems might a loose fitting grommet cause?

a vac leak and unmetered air situation.

 

[extremetrek]

Okay, so thats obvious enough, but what actual SYMPTOMS might it cause in the operation of the vehicle?

 

[Zero Signal]

Potentially pinging but probably not, and a minor funky idle. Nothing major, maybe not even noticeable, but it's one of those things you fix just becuase it's not right.

 

[91LX_5L]

humm mabye ill get a new grommit. mine slips in so easily takes NO effort at all to pull it out. ???

how can i tell if my pcv valve is worn? do the aftermarket ones work as good as ford ones?

 

[extremetrek]

Yeah thats why I was asking, I noticed when I did my intake swap that the grommet was pretty loose and I have recently had problems with idle but I think thats all timing related. Thanks!

 

[SeventyMach1]

how can i tell if my pcv valve is worn?

Test it by shaking it with your hand. (up and down) You'll hear it rattling inside. If it rattles good (everything moves freely) it is good. If it feels like it is moving really slow.... or sticks at times..... it is bad. Also..... all kinds of gunky buildup around and in the valve signify a bad one.

 

[HISSIN50]

To add to Justin's comments: there is a spring inside the PCV valve which can break or lose tension. The valve will still rattle, but wont necessarily function properly.

John et al hit it about the vac leak. Often a leak causes a hanging idle (like if one revs the motor and gets off the gas, it takes a bit to come back down to idle, instead of quickly returning).

Some aftermarket valves dont fit real tight in the grommet. I dont like spending more than I have to, but I do use Motorcraft parts for the valve, grommet and screen (though like I mentioned and John posted, parts' store grommets seem to do fine).