348 vapor canister purge valve removal

I just had my canister replaced....it was falling apart internally

 

hi ernie,
I dont know if the 348 section has a Fderrari parts equivalent thread or not but the Testarossa section does. It would be good if you could add this Ferrari part number and its equavalent in that thread, see here....

http://www.ferrarichat.com/forum/showthread.php?t=125008

P

 

I'm reading this article, all "la de da, I don't have any symptoms of this..." and then you mention the gas cap. OH CRAP! Yes, mine does a mini "whoosh" every time I fill up. OK, OK, off to the test bench we go.



Anyway, thanks for breaking the trail, Ern.

 

P.S. My luck it won't be the easily obtainable $90 part, but the, you-gotta-send-to-somebody's-cousin-in-italy-to-not-get-ripped-off part, the canister.

 

Yes, it's an inward whoosh. Still pretty moderate, i.e. I don't really have to pull on the cap to get it off, just lift it, but as soon as I do, I get a whoosh of air entering the tank.

Better safe than sorry, so I'll be looking at the valves soon.

 

But what if the new part is defective? Happens. Ferrari will pay to replace whatever the new defective part breaks, such as your gas tank. That's not a cheap Ferrari part! So Ferrari is pricing in a premium to pay for a potential defect breaking a more expensive part.

So here I am offering a defense of Ferrari. You are paying for a Ferrari warranty when you buy a part through them. If a defective new purge valve implodes a new gas tank, then Ferrari is going to buy your new gas tank (within say, about the 1st year of your installation).

Now, that being said, I'm as big of a fan as you for buying the off-brand parts to save money. I'd readily install the Kia purge valves rather than pay the Ferrari premium...but...I do recognize that when I buy the Ferrari part instead that I am getting something more than just the part. Ferrari is standing behind it (and not for free!). Anyway, if the valves in question are parts #21 shown in the diagram below (Ferrari #130978), then Ricambi has the Ferrari-boxed ones for $150: http://www.ricambiamerica.com/product_info.php?products_id=196477

That's the money quote. You have developed a *test* to see if this problem is on any of our cars! Very cool. Take a bow, ernie!

...and in that spirit, here is a tip of my own: put a little anti-seize lubricant on your fuel cap threads. You'll thank me some dark night when your gas cap removes properly rather than gets stuck shut due to age, rust, temperature, or fuel tank vacuum.
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"Ferrari will pay to replace whatever the new defective part breaks, such as your gas tank...."

Where in the world did you come up that? Sorry, I don't believe that for a minute. And if the customer installed the part himself, rather than having it installed by the dealer, I doubt if Ferrari would even pay for the defective part. Do you happen to have a parts invoice from a Ferrari dealer that includes a written warranty statement?

 

All that I saw was that Dennis McCann has the vapor canisters for $225 under Ferrari part #138419: http://www.allferrariparts.com/parts_list.php

 

That *is* a nice find - it is much, much higher, (nearly $900), at other outlets .

 

Fellas, I'm looking at the parts diagram for my t and what I am seeing has me really wondering if the faulty valve was the cause of your tank implosion, Ernie. The system is designed to replace the old fashioned tank vent which consisted of a small hole in the fuel cap. This was required since as the pumps pull fuel out of the tank, air has to come in to replace the pumped out fuel. Problem is that when the car sits, fuel evaporates out of the hole. So, close the hole and attach a vent tube to a canister that will catch the evaporating fumes from the tank and absorb them. The air comes in the tank at the bottom. The top of the tank has a line attached to the intake manifold so that when the engine is running, it will draw air in over the charcoal and evporate the absorbed gas and burn it. When the engine is running, the tank can pull air in through the cannister as the fuel leaves, but it has to pull it through the cannister and through the "rollover" valve, (Ferrari calls it the "Anti turning-over valve"). That is between the cannister and the tank to prevent fuel running out when if the car is upside down. Manifold vacuum is not enough to crumple the tank. But seal the tank shut and those fuel pumps could do the job. So, as long as the cannister is not plugged, and the rollover valve is not closed, you should be fine. Even if the cannister is plugged at the bottom, the valves should still allow enough venting to prevent collapse. Even if one locked shut, since they are teed together, the needed air should be able to enter the tank through the other one. I think that your more serious problem, the blockage that caused tank collapse was somewhere downstream of the valves. You've probably cleared it, but I'd keep an eye on it.

I also think that my tank's vent is starting to get plugged somewhere.

I think. I have not confirmed that the Ferrari cannister is the open at the bottom type. Still, something is not adding up here.

Really the way to test this might be to install a t between the rollover valve and the tank. Put a vacuum guage on it, run the engine and see what happens. If vacuum starts building disconnect from things one piece at a time, starting at the cannister to see where the plug is. Another method would be to plug the cannister's port attached to the valves and put a vacuum pump and guage on the port attachted to the rollover valve. You shold not be able to draw much vacuum unless the cannister is shot not letting air in.

Whattaya think?

 

I think that ernie's test is still valid even if the purge valve wasn't the culprit. Open the gas cap with the engine running. If there is a super strong vacuum on the fuel cap, then there is a venting problem.

If not, then no further vacuum analysis is required.

 

Yes, it is valid. A very simple and to the point test. I missed that. However the reason that I went into all the detail about how this system works is to point out that Ernie may still have an issue even if he now passes the "palm test". Clearly one of his valves was malfunctioning, but I don't think that is what caused his tank to collapse. Hopefully I am wrong, or at least hopefully whatever it was does not return. Also I am trying to suggest likely places to use to pinpoint a problem, once one is evident.

 

I hear you Ernie. You are right, but that just reinforces my analysis that the cannister has to be plugged for the valve to cause a problem. Just like you are saying, the manifold can pull some vacuum, (and the fuel pumps can displace some liquid). The air intake to keep all this from being an issue is supposedly in the bottom of the cannister. So, say if both valves are stuck open all the time, no vacuum should build up since air just flows in at the cannister. Unless it is old and plugged, hmmm? I bet mine is too. I won't have time to look at mine for a couple of weeks. The reason they have the valves, is that if they were open all the time you would pull too much "unmetered" air, not to prevent tank implosion.

 

That's when you cleared whatever was blocking it. Maybe?

That's probably all you needed to do to prevent further tank collapse. I'm not saying that those valves can be ignored: it they are stuck open that lets in unmetered air throwing your "lambda" out of wack. If they are stuck closed, then you don't dispose of the absorbed gas and who knows what will happen.

Of course if you blew air in so that it was coming out of the vent in the top, that is the reverse of the correct air flow direction so it may plug up again when the manifold is drawing air in through that route.

Would it be possible to blow air in the vent and see that it come freely out both exit ports: the one that connects to the manifold, and the one that connects to the tank? I would test them separately - plug one and test the other one.