Another Emissions Question

[NJFJ40]

On my 02/80 FJ40 - I just completed re-assembly on my exhaust manifold rebuild and smog rebuild. Runs well (after I reconnected the PCV hose that came off).

I have a small vacuum leak which I traced back to the nut that mounts the air cleaner to the carb. This is the nut that connects on top the air cleaner to the post that comes out of the carb. It is leaking at that connection. Note I do have the ring gasket on the bottom of the air cleaner where it seals to the carb and that seems to be fine. The leak is coming from on top the air cleaner at the nut.

I checked SOR but can't see if there is supposed to be some type of gromet or fitting here to seal the connection on top the air cleaner.

Any advice would be appreciated.

And Happy Holidays to all.

AndrewT

 

[Pin_Head]

You can just get a grommet at the hardware store to seal the leak, but it is inconsequential for emissions. The only leaks that cause emission problems are ones that occur below the air horn on the carb and alter the air/fuel ratio.

 

[NJFJ40]

Cool.

Thx PH. I already put a gromet in there just to reduce the flow (leak) and the truck idled much better. I'll go get the right size one and should be good to go.

AndrewT

 

[spotcruiser]

Yep. SOR has them. 012-03B A/C WASHER-1/75-8/87 1.80

They are steel washers with integral rubber seals. You need three for the air cleaner. Should use the stock wingnuts also, because the inside of the washer seal is sized correctly for the lower portion of the wingnut.

A very small air leak at this point will not affect engine performance, but will let dirt into your carb. Another good thing about the OEM seals is that they keep water out. Up here in the Pacific Northwest, condensation on the underside of the hood during the winter fills the depressions (around the air cleaner wingnuts) with water.

Dealer probably still has both of these also. May want to check for best price.

Good Luck.
Todd Bull.

 

[Koffer]

You can also find these on alot of japanese cars in the junk yard . they fit well in your pockets when your looking around for bigger better things like $8 birfeilds that someone already took off for you
I didnt need them but at that price you cant pass it up when someone else did the hard work in the nasty junk yard dirt

 

[Pin_Head]

Cool.

I already put a gromet in there just to reduce the flow (leak) and the truck idled much better.
AndrewT

That sounds mighty peculiar. The only thing a leak like that should do is maybe let a little dirt in. The only way I can envision it having an effect is if the idle mix is lean, the leak was substantial and your air filter is so clogged that it actualy produces a choke effect.

 

[NJFJ40]

More Problems....

OK - the idle was somewhat better but not much. It seems rough so I assume I have to adjust the carb though I didn't change any adjustments on the carb when I removed it. Also, with the choke fully engaged at idle, it doesn't seem to rev as high once warm as it did before. Then, when I run it at high RPMs with the choke off , it seems to lose power as if the choke is on (though it is off). Any ideas?

Before, it ran well but I had an exhaust leak so I took the whole thing apart and rebuilt. I bought all new emissions gear (VSVs, BVSV, etc..) and gaskets and vacuum lines and installed according to my emissions FSM. In doing so, I noticed a whole host of errors from PO where certain hoses were either missing or not connected to the proper location.

I plan to trace back the entire emissions curcuit to ensure all connections were made to the correct location. I also plan to test each individual circuit as per the FSM.

Besides this, what other major items could be causing issues? Timing? Plugs? I want to make sure I start with a 'clean' foundation before I start further dignosis and possibly compound problems. Could a fresh emissions system now unearth other problems which were there before but not noticeable?

TIA,

AndrewT

 

[NJFJ40]

Anyone?

To narrow down my question - I am wondering if a newly repaired and properly functioning smog set-up could cause me to re-adjust the carb (and timing?) after rebuild. Intuition tells me yes. Just need to get some time to go poke around if others think I am heading in the right direction.

AndrewT

 

[spotcruiser]

Depends on how the carb and timing are set to begin with. With properly functioning smog system, everything else should be set to specs. You can probably advance the timing a little, but everything else should probably be set to spec in order to work right. Smog equipment is all inter-related.

 

[NJFJ40]

Thx - Gonna post a new thread as I just got some more info from vacuum readings.