Roll-over Check Valve (sorry so long)

Hey everyone...I've been lurking/searching for a couple of months now. I picked up 79 CJ5, 258, etc... as a restore project. I've run into a few areas where searching this forum and the net just hasn't paid off. So I'm hoping for a little help...

The CJ already has the Weber Carb conversion...so most of the stock vapor lines not needed with the conversion is gone or rotting away. Which brings me to my problem..

I went to fill her up and ended up leaking gas all over the station (not fun). The two vapor lines into the rollover check valve/liquid check valve decided then and there to rupture (dry rott final gave way). Further inspection reveals...the rollover check valve and liquid check valve are also completely done in by the years and weather. QUICK FIX - I looped some rubber fuel line on the vapor outlet into itself.

Search the web vigourusly for NOS/replacement parts...nothing. Go to the dealership...not in production anymore...

Questions

1. Where can I get replacement parts? If it's even neccessary...
2. Should I expect "vapor lock" in the future since I looped the vapor/vent lines (negating the vapor canister)?

Any wisdom would be appreciated

Joe
Colorado Springs

 

Wow, tough crowd...back to lurking/searching.

Joe

 

If it's not needed for emissions in your area, leave it looped or just cap off at the tank.
You won't have any vapor lock problems with them looped/capped off.

 

Ok, don't discard the vapor recovery system unless you have to. The system vents your tank properly, and has very low maintenace requirements, and no performance penalty.

Without vapor recovery, you ahve to have some other way to vent the tank. In the olden days, this was done using a filler cap with a vent. If you don't have a vent, if everything is sealed, you'll build up a vacuum in the fuel tank that will prevent your fuel pump from sucking gas from the tank. You'll also have the possibility of building up positive pressure from the vapor pressure of the gasoline, and the pressure blowing out somewhere.

If it were mine, I'd fix the vapor recovery system. At least one style of liquid check valve is available for the Wagoneer on the BJ's FSJ site. You could make that style work, or the correct replacement amy be available.

The roll-over valve keeps liquid fuel from draining in case of a (guess). You don't need it for everyday operation, and leaving it out would be no worse than using a vented cap, I'd think. Only the CJs came with this valve, which says ... something.

<edit> Just a comment - In CA, every car 1976 or later has to have all the emissions equipment it was delivered with. There is a visual and tailpipe inspection, and they are thorough. I would expect other states to start following CA's lead - I think areas of AZ are already as strict as CA, if not stricter. My point is that, even though your Jeep isn't smog-checked where you live now, there are areas of the country where it would be, and these stricter standards could be coming to your state.

In the past, there's been a lot of misguided enthusiasm for stripping every emissions system from hobby cars like ours. IMO keeping these systems, if you have them, makes a lot more sense than removing them. Vapor recovery is perhaps the most benign and beneficial of all emissions systems, and IMO removing it is particularly wrongheaded.

 

Arizona only has testing in the Tucson and Phoenix areas. Most states have no inspection for emissions and a huge chunk of them have dropped safety inspections in the last 20 years.

If the system can easliy be fixed I say fix it, if parts are unavaillable plug it and forget it.

 

Well tomorrow will be the test, got it registered and plated.

Thanks for the shared experience...I've been a TJ, XJ suspension/body protection fabbing guy for years. This CJ endevour is a whole new beast.

Thanks again,
Joe

 

BTW if the vapor canister isn't connected under the hood properly, the whole system is pointless. The earlier systems used used the draft from the air cleaner snorkel to purge the canisters (through the 70s?), but the later systems were connected directly to manifold vacuum via a purge valve in the canister. I don't think there's any way you can make the earlier systems work with anything except the original air cleaner. The '72 and earlier systems are even stranger, seeming to purge directly into the crankcase (I'd have to look at the manual more closely).

If you have one of these systems, and it isn't purged regularly by engine vacuum, the charcoal in the canister will become saturated and you'll be simply venting the tank through the bottom of the canister.

 

I have them looped together. I use a vented gas cap. The cap seems to work properly, I do not hear any pressure releasing from build-up when I open the cap.

 

Chuck,

Please define "our area". Does it include Denver? I haven't heard anything about it, but then, I don't follow the news very much. Can you give me a reference article that I could read up on it? I'm not doubting your word. I'd just like to be more up on this subject.

tommy b

 

Bummer.

tommy b

 

I'm not sure who I should ask this ? because of the age of the discussion, and not having ask a ? yet on the forum. Here goes I'm getting my feet wet or tires wet depending how you look at it. I pulled into my garage after taking the cj out for the first time after replacing rear axels, brakes and found a gas leak coming from my drivers side rear tucked up in there. I did a little browsing through ECJ5 and found the names of the culprits and that I could get the ROV from the Delorean Motor Company but haven't found the LCV. My LCV has a crack it in the bottom and spitting gas. Does anyone know where to get the LCV? Since reading Tim's reasoning for keeping the original equipment I would agree, just not sure where to find it all.

 

Hi Jeff - I presume this is for the '78 CJ-5 you have in your profile? Best to put that information in your message or in your signature file. Is the picture you show from the '78 TSM? Again, I presume it is, since the '78 TSM is present on the Tom Collins site. Not to pile on, but I would have started a new thread with a descriptive title rather than appending your question to a very old thread.

IIRC MTS sells a LCV work-alike. MTS COMPANY, L.C. - Jeep CJ/YJ Gas Tanks Look at JLCV-1. Your diagram looks the same as what Jeep started using in 1973, without the roll-over valve. I'd guess the roll-over valve is just that, to keep the tank from emptying through the vapor canister if the Jeep is upside-down. Seems worthwhile.

 

Thanks Tim for the advise on using the forum! I will include the specifics on my vehicle in the future. This tread was very helpful. I really appreciate you getting right back to me with the info.

 

Barring using oem style parts, another option would be to plug one of the ports and use a simple rollover valve with a fuel filter on the other. Rollover valves are common in racing and can be sourced from Summit Racing, Jeg's, etc. This would filter and vent the air yet keep it from leaking in case of a rollover or serious off camber situation.

 

i found this liquid check valve, thanks Tim for the link, I’m assuming it’s the same principle as original just built different. I would just need to get the ROV to go with it.