Heresy

[Bryan Boyle]

Going to ask a question which some may view of heretical...after my description of the current state...but here goes...

I'm continuing my quest to return 3291R to decent mechanical condition (acknowledging that I'm also working on renovating the interior to some extent...).  Somewhere along the line, a (d)PO thought it was a good idea to remove all the fuel vapor containment devices...the catch can, charcoal canister, and the VCG breather (PCV, after a fashion) gubbins and throw them in the packing cases of parts that I'm digging through. 

In doing so, they just cut the vent lines from the fuel filler necks and left open to the atmosphere.  Accordingly, I get a whiff of gas smell in the cockpit from time to time.  And, to be honest (though I'm not a tree-hugging ecomentailst), it does bother me a bit that I'm just venting hydrocarbon vapors to the outside world when I don't have to.  So...I'm starting to assemble the bits to put things at least back together to close off the system to free atmosphere.

To that end, I've acquired a nice air/oil separator for the PCV system (and will go about plumbing that in, mounting the can in the right rear dead space next to the boot and running the air back to the backplate of the carb air box), and would like to plumb the fuel vapor containment system.  For that, besides a healthy run of hose to run back and forth as per the diagram in the parts manual...I need to source a charcoal canister...if not to feed back to the base of the carbs (the ports for that are capped off right now), at least to filter the vapor from the ports on the filler neck.

So...has anyone sourced a useable charcoal can?  Is my idea without merit?  z

Heretical, I know...putting emission stuff back on...but, thinking of doing my small bit (not to mention not getting fuel vapors in the cockpit...).

Thoughts?

[Kendo]

My car is in that state. And I have the gas smell (or did before I emptied the tanks). Researching vapor containment, I saw quite a few charcoal cannisters for sale, in all kinds of different shapes. So you shouldn't have any trouble finding one. I think you have to keep it above the neck of the tank, to keep gas from spilling down into it. Some one here suggested putting RC plane gas engine filters on the vent ports of the gas tanks, to provide a slight pressure on the vapors to stay in the tank. There are also roll-over valves to keep gas from splashing past the vapor ports of the tanks. I haven't done any of these yet; I'm still painting the body.

Let us know what you decide to do. I might want to go that way.

[BDA]

So...has anyone sourced a useable charcoal can?  Is my idea without merit?

I bought one when I was building my car but I never hooked it up (I probably still have it around somewhere). My fuel tanks are vented with no hoses or other hardware. I did have a bit of fuel smell when I first drove my car but I believe the cause was a fuel leak that I have since solved since I no longer have that smell and haven’t for a long time.

[EuropaTC]

Hi Bryan,

I'm not going to say "aaaagh, no, no, no !" on reinstating emissions gear, but why not simply duplicate the UK spec cars by blocking off the extra holes ?

I can honestly say I've never had fuel smells inside the car or even the engine bay come to that. Venting is by the filler cap and I would have thought that what comes out of the cap is nothing compared to what comes out of the exhaust pipe with no catalyst fitted ?

Random thoughts....   if it's a charcoal canister trapping vented fuel, does this have a life cycle and replacement interval ? Do they get "full up" at some point ?

Brian 

[Bryan Boyle]

Hi Bryan,

I'm not going to say "aaaagh, no, no, no !" on reinstating emissions gear, but why not simply duplicate the UK spec cars by blocking off the extra holes ?

I can honestly say I've never had fuel smells inside the car or even the engine bay come to that. Venting is by the filler cap and I would have thought that what comes out of the cap is nothing compared to what comes out of the exhaust pipe with no catalyst fitted ?

Random thoughts....   if it's a charcoal canister trapping vented fuel, does this have a life cycle and replacement interval ? Do they get "full up" at some point ?

Brian 

Our gas caps aren't vented (different part numbers for both the flip cap and the filler neck per the parts manual), hence that long canister at the front of the engine compartment ostensibly to capture raw gas (#14 on TC parts page LA) the vapors of which were to be drawn through an activated charcoal filter  (LA #16...remember Lark cigarettes here in the US?) by the vacuum in the carburetor through #19 in diagram LA...and the pressure equalized by part #18, which was connected to the airbox. All very Rube Goldberg, but then, the US EPA was never known to impose regulations that were based on hard science rather than what was fashionable at the time. 

Yeah, the do have a life limit; current thinking is somewhere around 100K miles, but may be wrong.  The systems have gotten more and more complicated as time has gone on, and no doubt, the pollution has markedly decreased where they've been implemented, and these initial halting steps were the beginning of what we have today.  (remember 5mph bumpers?  What they've morphed into?  How about the interstate 55 mph speed limit? 85 mph speedometers? WIN buttons?)

[Bryan Boyle]

Just to update...found a 'universal' carbon canister for all of $70 USD.  Has all the right nipples (vapor, vent, and carb).  Now to plumb it all in.  Going to use the same nylon hose that the company seemed to prefer for fuel liquid, and found the nipple on the air box, both filler necks, and some right angle fittings to pop onto the carbs flanges (which were in the Boxes O'Parts that came with the buggy.

Will report back after getting it done (which will be in a couple weeks due to work travel next 2 weeks...could do it tomorrow, but have tix for the Red Sox game against St. Louis tomorrow in Fenway...).

And, oh, the 'rebuilt' head came in that was listed in the FS section...but it's so dirty (and no assembly lube on anything!) that I'm going to hand off to Union Jack Exotics near my PA residence to go thru and make sure everything (clearances, seats, valves, bearings, and a good cleaning, etc) are done before tackling swapping out my existing for an O/H head.  3291R is running pretty good (starts right up, albeit rear 2 plugs say it's a bit rich, front 2 are nice tan color...maybe drop the rear needle a quarter turn and see..none show any oil contamination, has decent acceleration, shifts pretty much as it should, and brakes work...clutch still judders a bit sometimes, but going to put in the alternative rear cable mount in to see if that cures it...) right now and don't want to jinx it...and get a couple more months out of the old gal before starting the heavy mechanical stuff...