355 Anti Rollover Valve

The ROV is not serviceable, you remove and replace. There are several threads on doing that and some xref parts as well.

 

From Ernie's DIY...
https://www.ferrarichat.com/forum/threads/348-anti-rollover-valve-anti-tilt-valve-replacement.453019/

 

I also tried to detach the rollover valve from the vapour separator recently, but the forces required were more than I was willing to exert (knowing that the parts were no longer available). The manual wasn't making much sense and I was just curious about the construction of the vapour separator.

Ricambi America list the vapour separator and the rollover valve as separately available items.

https://www.ricambiamerica.com/car-diagrams/ferrari/v6-v8/355-group/f355-m2-7-1995/antievaporation-device.html

I assume you are talking about item 21.

21 is the rollover shutoff valve (mounted on the "vapour separators").
22 is a two way breather valve (the red thing).

Since the rollover valve is a plug-in part of the vapour separator, I cannot see it as being an aftermarket item.

Here is the F348 valve as a comparison:

https://www.ricambiamerica.com/car-diagrams/ferrari/v6-v8/348-group/348-1989-1992/antievaporation-device-valid-for-catalytic-vehicles-and-sa.html

Two different beasts

Cheers

 

Here's my 5.2 Rollover Valve/Vapour Separator

Fuel leakage disappears

I had a split pipe behind it.

 

Here are some photos of the vapour separator without rollover valve:

https://www.ebay.com/p/Ferrari-F355-Fuel-Disaerator-157977-ANTIEVAPORATION-Device-Dis-aerator-355/1029913359

(EDIT: Sorry, I copied and pasted the link, but it's not working in FChat)

Here's the photo instead:

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Friction fit (after you take off the clamp)?

An oddly cheaper item including the rollover valve:

https://www.pacificmotors.com/auto-parts-shop/ferrari/ferrari-f355/fuel-system-vapor-seperator-disareator-157977-oem-ferrari-f355-spider-1995/

(EDIT: Seems the early 2.7's had a different vapour separator with the part number 157858, later 2.7's with the part number 15797)

 

Actually that's not a bad idea... Definitely worth a try!

 

It looks like the rubber seal is damaged in that photo. Maybe a screwdriver was used to separate them. Unfortunately, we don't know if the plastic rollover valve survived the separation. For what it is worth, the seal is still available (P/N 155313)

The rollover valve is also found on lots of other Ferraris (also NLA) P/N 124193

 

I had to drill a little bit to get the pin into the rollover valve and it took some pressure/force to get It in, which seems good because it's more secure but I'm worried I might of pushed the pin a little too far in, I'm not sure if it's just vapors that goes through there or if gas comes out.
Can you tell me the size of the T-Connector I would need if I go that route?

 

I'm just using the resources that are available, Paul All it takes is practice. Ricambi and other parts suppliers provide us with the parts diagrams and part numbers. With the part numbers, we can search for pictures on eBay, etc, using a simple Google search phrase "Ferrari part XXXXX".
At the risk of breaking the rollover valve, I think the use of carburettor cleaner (in situ) sounds like the better option to free the ball or whatever is in the valve. I'm not sure what effect WD40 will have on the rubber.

Sorry, Bryan you've lost me on this one. Pin?

 

Paul,
I think if you remove the ROV and shake it back and forth, you should hear it rattle. If you remove the vapor line (on top) and blow some compressed air into the fuel tank you should have air coming from that port. Just be sure to use a regulator set really low to avoid subjecting the tank to high pressure. That will at least confirm that it is allowing vapor to pass. The red and white valve that releases vapor to the charcoal canister may hang up and stick. That could cause excessive tank pressure. I think if you read some of the posts on here you will find that most 355's have this issue. I know I was concerned about this right after I got my car, because of the amount of pressure I had release from the gas cap when the car was hot was in my opinion too much. I replaced the vent valve with a new one to see if the condition got better, but have not checked on it since. I doubt it changed anything. Hope this helps.

 

The roll over valve is pretty genetic. You can probably find one that fits at your local auto part store I found this, which looks like it might fit, in about a minute.

https://www.everythingcarts.com/p-8439-e-z-go-rxv-gas-tank-rollover-valve-fits-2008-up.aspx

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Google "Nissan 240SX Maxima Sentra Stanza Fuel Tank Check valve" for another option

 

If the Ferrari rollover valve has a barb on the end of the tube like that one, I'm not surprised we can't get the darned thing out.

That Nissan Maxima rollover valve has the pipes pointing in the wrong direction. The valve's entry and exit points need to be at right angles.

 

I purchased one at Scuderia parts. PN 170442 tank ventilation valve

 

PN 170442 tank ventilation valve not the roil over valve, but agreed it could be the problem, and more likely is since the roll over valve is normally open, unless you live in AU.

Vent valves are cheap and available at local auto parts stores. Just take the old one with you and they will match it. Realize that most of these parts are standard, off the shelf parts from regular suppliers. They are not unique to Ferrari or custom made for Ferrari. No need to spend extra for a Ferrari PN + shipping when you can get it locally.

Here is another source for a roll over valve that might fit. $5.28 -plus shipping. For that money I would buy it just to see if it fit.

https://www.usplastic.com/catalog/item.aspx?sku=14535&gclid=EAIaIQobChMIjavr7pP44QIVR0SGCh19IAOFEAQYDyABEgKN4_D_BwE

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John, could you clarify your comment on the rollover valve in AU? The Ferrari parts manual only lists one part number for all F355's and the fitment orientation is the same.
There are a few variations in this system in general, however. The 170442 valve is not fitted to later model USA, Canada and AUS cars, but rather 174594.

 

A little joke Ian. Everything is upside down in AU, so it follows, your car is rolled over.

 

Sorry, John... missed that one.. too early in the morning here )))