Question for the carburetor Guru’s (1 Viewer)

[BuckMark]

Hi Folks,
Im working on a 78’ FJ40 (Cali smog) project & having a great time! My question is, can I use a 77 California carburetor (26k mi & clean) on my 78? The only noticeable difference I could see, is the 78 has a bib & hose on drivers side that is hard piped to the charcoal can through the Outer Vent Control Valve (on the can). Can the OVCV on the charcoal can still be fed from the 77 carb?
Thanks for any input guys.
Mark

 

[thebigredrocker]

Mark's Off Road would know. Or maybe @Fast Eddy or @Spike Strip

 

[BuckMark]

Bump..... help?

 

[thebigredrocker]

In case you are working in it now and don't get responses, here are some OVCV threads

Search results for query: vent control valve

forum.ih8mud.com

 

[BuckMark]

Thank you thebigredrocker. I appreciate the links. Ive been reading them all day. I think FJ40Jim covered a similar question in an old post, hopefully he’ll see this or I can message him.
Mark

 

[thebigredrocker]

Yeah, without generous knowledge sharing from professional mechanics like FJ40Jim mud wouldn't be quite the same. Hopefully he's seeing some fruit from all his technical support.

 

[Catching Neutral]

May or may not help. SOR has carb identifier photos front, back, side and top in their carb section. You might be able to study those photos and deduce something

 

[AntFarm]

I'm not a carb guru, I just enjoy working on them. However, the main difference you are referring to is that 7/77 and earlier do not have a float bowl vent on the drivers side. But your current emissions setup is for a 78 which connects a float bowl vent to the OVCV. I would think a simple remedy for this is to plug the port on the OVCV that opens the float bowl vent , remove the hose and hard line between your (previous) float bowl and the OVCV, and then just let the purge system run as normal. Be sure to keep the rest of the canister system (line from the fuel tank, VSV, line to the intake), to keep your vapors all sealed up. A bigger consideration for you in California is, what are your emission requirements? Is it a sniff test, or a visual? If you require a visual inspection in your area, they might pick up on this mod, so you will need to research this first. Good luck!

 

[BuckMark]

AntFarm, Thank you for the suggestion! I appreciate it. So if I understand correctly, I would remove the rubber hose & hard pipe from current 78 carb (float bowl vent to OVCV valve), and the OCVC valve itself . Then plug the hose from (now removed) OCVC to charcoal canister. I can then install the clean 77 carb.without the float bowl vent Correct?
I am in the process of sending the 78 carb to FJ40Jim, but I’m hoping your suggestion will work temporary solution. (and a easy switch back to the 78 when completed).

 

[AntFarm]

AntFarm, Thank you for the suggestion! I appreciate it. So if I understand correctly, I would remove the rubber hose & hard pipe from current 78 carb (float bowl vent to OVCV valve), and the OCVC valve itself . Then plug the hose from (now removed) OCVC to charcoal canister. I can then install the clean 77 carb.without the float bowl vent Correct?
I am in the process of sending the 78 carb to FJ40Jim, but I’m hoping your suggestion will work temporary solution. (and a easy switch back to the 78 when completed).

I didn't know you were planning on reinstalling your 78 carb. That changes my recommendation a little. If that's the case, I would remove as few components as possible when running the 77 carb, so that changing back to the 78 is seamless. I wouldn't remove the OVCV, and only remove the soft hose between the float bowl vent and wherever the hard line begins (if you have a hard line at all). Just plug the port in the remaining hard line to the OVCV, and leave it all attached. Originally I was recommending that you leave the OVCV attached and plug it right at the valve, but now I would try to keep any hard lines still in place, since this 77 carb is just temporary. After JimC works his magic you will be really happy.

 

[Fast Eddy]

Make sure you tell Jim you have to pass smog. His 'normal' choice of primary jet size won't pass. It has to be the small one that came in a CA carb, .028 or something like that.

If you have a carb jet tool you can run one for the test and one between tests. I don't though. I just live with the lower perf and cleaner smell at idle.

I'd have to go out and look at how my '76 is plumbed from the charcoal can to the carby. I sold my '78, so I can't look at what the stocker looks like, but I was in there recently, so I have a fairly recent memory of it. My '76 is a frankenstein with a fj60-era 2f and a '75ish carb that was rebuilt by Mark A.

The smog man is going to want to be made to believe that it's all bone stock. He won't pass it if he can see anything blocked off. BBs in vaccum hoses will pass though. There's no functional check and no real check of hose topography. Everything you have has to go somewhere and every port has to have a hose connected to it.

My '78 failed the visual inspection because the rubber air intake hose was cracked. It was still pulling air from the stock air horn. My '76 has no stock air horn or rubber hose at all. I'm interested to see if they notice that it was supposed to have one. I'm guessing not.

 

[BuckMark]

Thanks for the update AntFarm, I will leave the parts attached. I’m glad to hear that it’s that easy. Email has been sent to Jim at TLC!
Fast Eddy, thanks for the tip. I’ll be sure to mention to Jim to choke it to Cali specs I’ve been trying to keep all the smog gear intact, & connected. Hoping my smog guy is easily distracted . Thanks again fellas, I appreciate you.
Mark