gas tank filler neck?

[blzn1]

Hey gents,
gotta smog my beast. At the pre-test (scam) the guy told me i need the filler neck with the flapper. My question is this. Do I need this to pass smog? Mine does not appear to have one. Also, he checked the timing and it showed 48BTDC. WTF? What sould be the likely cause of this. Any leads on where to get the filler neck is greatly appreciated. LMC carries one, but for 84-91. Is this the same gas tank?

thanks
Rick /forums/images/graemlins/dunno.gif

 

[dyeager535]

Well, if they say you need it, you probably do.

IIRC the change in the fill necks was made for the conversion to unleaded gas. Before my time, but perhaps nozzle diameter is smaller on unleaded pumps, thus the bigger leaded nozzle wouldn't fit in the unleaded vehicles fuel necks?

Anyways, I believe all the "hidden" (gas door) K5's and Suburbans share the fill neck, meaning either will bolt up ok. (although there is a difference in diameter for the actual fill hose between early/late, guessing with LMC's description, '84 was changeover year)

When looking for one myself, it seemed fairly common for people to rip that flap out. (either that or it breaks off easily)

 

[blzn1]

thanks for the info /forums/images/graemlins/thumb.gif

 

[gravdigr]

That little plate is called a restrictor and if your vehicle came from the factory with a cat ie unleaded fuel only it will require one. Why is beyond me since leaded gas is no longer sold at the pumps. I learned this with my 79 as when I got it there was no gas tank or filler neck. I snagged a filler neck out of a military blazer which of course was a diesel and had no restrictor plate.