79 Fuel Filler

[iflyfisher]

I have a donor bed from a 79 that will be going on my 73 K20. The bed didn't come with filler pipes or hoses. I was on LMC this morning, and I believe a filler pipe from a 79-83 with a filler hose from a 79-81 is the right combination. Based on the drawing on LMC's website, the filler pipe likely bolts to the bracket that is set back a few inches from the door. What I am not clear about is what may have attached to the inner side of the fuel door opening. When I open the filler door, I see a missing mounting bolt for the door and a missing rubber stop. But there are also three other holes that perhaps were used to attach a housing. The only housing LMC shows on its site is for a 84-87 style door. Anyone out there with a 79-83 style bed that can share a picture or two and enlighten me? Thanks!

Ken

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[bucket]

That does not appear to be a '79 bed. It appears to be an '84+ bed that used the plastic filler housing.

 

[iflyfisher]

Thanks Andy. The guy I got the bed from said it was from a 79. It has the fuel shield from what appears to be an 81-83 I believe (see image below). The tailgate is also late 70's style. The only reason I care is so I can get the correct fill pipe, hose, and housing. I'm not familiar with the various fuel filler/door iterations and am going only by what I see on LMC's website. Doh...nothing is ever straightforward with this truck!

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[PrairieDrifter]

On my 79 they are definitely floating.

 

[iflyfisher]

Hey Mason, would you mind posting a picture of what lies behind the door of your 79? Does yours also have the shield on the inside panel below the door?

I looked up the housing for an 84-87 on LMC's site. It does show three mounting holes, likely matching the three holes in the side panel behind the door. Maybe I need the filler pipe for an 84+. If that is the case, will the 82-87 filler hose work with my old 73 tanks?

Thanks.

 

[PrairieDrifter]

Hey Mason, would you mind posting a picture of what lies behind the door of your 79? Does yours also have the shield on the inside panel below the door?

I looked up the housing for an 84-87 on LMC's site. It does show three mounting holes, likely matching the three holes in the side panel behind the door. Maybe I need the filler pipe for an 84+. If that is the case, will the 82-87 filler hose work with my old 73 tanks?

Thanks.

I'd have to double check, but I believe it's only the filler neck in the hole, don't believe there is any splash guard.

The hose should work as long as the diameters are the same. I'm not super well versed in the dual tanks as all of mine have been good working order other than selector switches.

 

[Turbo4whl]

Questions, 1973 has the fuel tank on the passenger's side? Newer truck, door and filler on driver's side, or duel tank, filler on each side. 1973 tank fitting is smaller than the later models, do you have a newer tank?

 

[iflyfisher]

Thanks Mason. I thought I had read somewhere that the tank openings were a different size from 84 onward, but I really don't know.

Wayne, my 73 K20 has the stock dual tanks. The donor bed, still not sure of the year, has dual doors. I go back and forth about replacing the tanks. LMC shows different 20G tanks for 73-81 and 82-86. I don't know exactly what the differences are, e.g., exterior dimensions, filler hose connection, sender unit opening. I won't be installing the new bed for a while, so I am trying to sort out now what I need.

 

[bucket]

Thanks Mason. I thought I had read somewhere that the tank openings were a different size from 84 onward, but I really don't know.

Wayne, my 73 K20 has the stock dual tanks. The donor bed, still not sure of the year, has dual doors. I go back and forth about replacing the tanks. LMC shows different 20G tanks for 73-81 and 82-86. I don't know exactly what the differences are, e.g., exterior dimensions, filler hose connection, sender unit opening. I won't be installing the new bed for a while, so I am trying to sort out now what I need.

Iirc, the filler hose connection at the tank is larger starting sometime in the early 80's.

 

[Radiohead]

Hey Mason, would you mind posting a picture of what lies behind the door of your 79? Does yours also have the shield on the inside panel below the door?

Timing is everything.

I am in the middle of redoing the steel and rubber lines on my '79. It is going back together when some parts show up, so I figured I'd get pictures for you of what a '79 CA emissions big block dual tank design looks like. I did it tonight because I may forget in the excitement and not get any before pictures.

So, this is the fill hose assembly off the driver's tank off its nest

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Closer look at mounting tangs on the money end of the circuit

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Now a look in the driver's side fuel door area

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Looking at a different angle, you can see some sort of a skirt/splash shieldy object in there and on this truck it's made of steel. 18 GA maybe?

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Now, that's driver's side. Passengers next.

 

[Radiohead]

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Looking at the other side is a mirror image but here's what stuff looks like

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This fill hose assembly hasn't been messed with yet, that's 1979 waving a hand at us from the passengers tank. Oddly enough, I keep seeing reference to that tank as a main tank and drivers side being an auxiliary.

Also had fun fitting a steel line for the pump to carb section as well. Didn't come with one when I got it. No more fuel delivery hinkeyness once the tanks go back in.

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It's the little things. Anyone been around a while understands that.

But yeah, I broke that egr vacuum switch getting happy during persuasion. Oh well.

At this point it's therapeutic. I just wish it were spring and not fall.

 

[bucket]

I forgot I had these pictures. On the left is the '79-'81? style. In the middle is the '82?-'83 style... notice the larger hose at the tank end and the different breather hose hookup. On the right is an '84+ filler that's meant for use with the plastic shroud.

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[iflyfisher]

You gents are awesome! Thanks Eric and Andy for taking the time to post some pix! Huge help. After looking at the pix, I do think the bed I have is an 84+ as Andy earlier suggested. Given that, is there a fuel hose that will connect the shorter 84+ style filler pipe to my 73 tank? I have been debating about replacing the tanks. This may make the decision for me.

Eric, nice job fitting that hard fuel line to the carb! My garage schedule is the opposite of yours. I don't work on my truck at all during the summer. Too hot here in the desert. My garage time is late fall through until mid May. So, I am just getting back to mine after 5 to 6 months off.

 

[bucket]

You should be able to use a '79 style filler hose, the '82+ vent hose, the '84+ filler neck and the '84+ shroud.

Or if you replace the tanks, just get the later ones with the larger filler opening and use everything '84+ style.

 

[iflyfisher]

Thanks Andy. You have been a huge help!