Fuel Evap Check Valve Replacement (1 Viewer)

[Spike Strip]

Just an FYI for anyone who finds that the evap check valve is bad or missing and might be smelling fumes in the cabin, or getting excess pressure in the tank.

The OE valve is still available from Toyota, for around $55, and I can't argue with it lasting 40 years, but this is an alternative for around $25 shipped.

This check valve from McMaster-Carr works perfectly and is high quality. It's for Gas and Diesel, opens at 0.3 PSI .... Couple of 1/4" barbs and you're good to go. I used a female x female version - they also sell it as a male. Your choice. I got the female 'cuz I knew it would argue with me

Part # 7775K52

McMaster-Carr

 

[LAMBCRUSHER]

MC is the poop...

 

[sggoat]

language not allowed on MUD----

 

[Spike Strip]

Shatko.

 

[antFJ]

Brilliant

 

[LAMBCRUSHER]

sorry, I grew used to the robot protecting you guys; will try harder...

 

[GA Architect]

That I like!

 

[antFJ]

sorry, I grew used to the robot protecting you guys; will try harder...

god forbid anyone gets offended these days. Wouldn't want to lose MUD to a lawsuit.

 

[LAMBCRUSHER]

honestly, I thought it didn't matter anymore...I mean...look around, right? but hey, like I tell the kids, there aren't any bad words, just some people feel bad when they hear certain words...this is what happens when you mollycoddle, America. make the kids cry...

 

[Weber Sarge]

Great solution - gonna try it on my '77 since the original wants to split the tank despite cleaning it twice ...
Sarge

 

[micruz60]

Great fix, going on my to-do list.
Perhaps an addition to the cheap mods <$50 FAQ?

 

[powthief19]

Do these original check valves go bad? Are they supposed to be replaced at a certain interval?

Toyota is sure proud of them: 90917-10020 - Genuine Toyota VALVE, CHECK

 

[ginmtb]

I think they can clog up over time or the valve can fail. Something happened with mine as it was causing significant pressure in my tank - sounded like it was going to split a seam. So I removed it. Everything seems to work fine without it. FYI - I have capped my fuel return line since I have a Trollhole carb which doesn’t have the return line. Not sure if that was part of the problem. Can’t imagine it being but who knows. I also replaced my charcoal canister thinking that might be the problem. But even with new canister the pressure was still building up badly.

What is the purpose of this check valve? Keep some vapor inside but then relieve the pressure when it gets too high? Am I venting fumes unnecessarily by having removed it? I don’t have a gas smell in the garage... this looks like an interesting solution. Just wondering if I need it since all seems to be fine.

 

[GA Architect]

Just wondering if I need it since all seems to be fine.

I installed a new check valve, but it made quite a bit of pressure in my system. Thus I re-plumbed my fuel tank vent line. When I did, I removed that check valve and ran straight to the charcoal canister. My CC is plumbed to the rear of my rig thru the frame, vented to atmosphere. Been running this way for a few years now, doesn't seem to bother the performance of my 2F, nor do I get gas fumes in my cab either.

Note, it has been discussed a few times about drilling a hole in the fuel cap to relieve pressure, so I don't see any difference of removing the check valve.....but I'm an architect, so my reasoning may be flawed.

 

[Beehanger]

Resurrecting this thread, could use some input. My 60 doesn't have the check valve in the vent seperator area, but im thinking of installing one custom after reading this thread. Ill get the mcmaster part and the toyota valve, figuring that this will help the vapor in the cab issues im having before it can hit the seperator. Apparently only german and european 60's had the valve there, mine is at the block but has already been replaced along iwht the cansiter.


P.s. here's my troubleshooting thinking process if this is

Alternative explanations:
1.) upper vent hoses need to be repalced along iwth the venting seperator.
2.) is there a check valve all the way in the fuel tank area that could be old and clogged or is this only for Fj40's? (see photo)\
3.) I've read guys have issues with the seperator sometimes getting clogged, has anyone seen this?

4.) Finally, I suppose it could be clogged somewhere all the way back in one of the meta vent lines going under the truck towards the engine bay as the truck sat for a while before i bought it 3 years ago. If you have any ideas much appreciated, trying to car camp in this thing over the holidays and rather not have fumes haha.

Best,
Dan