Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

OK, spent the last 2 hours reading every thread I could find on replacement in cab gas tanks.

I have a 72 K10 with rust inside the tank. Just had Lars rebuild my stock carb and don't want to clog it all up.

My tank appears to be an original EEC tank, however, there is no sign of the 'canister' anywhere under the hood. Does anyone have a pic of what a complete EEC system should look like?

If my EEC system is not 'complete' should I bother ordering an EEC style tank? I don't need the truck to be perfectly original. Would the older style tank be a direct bolt in as long as I get the correct gas cap?

I've read that I need to get the Canadian-made spectra tank and not the taiwanese one. It appears nobody actually makes a correct 72 EEC tank reproduction with the 1.5" neck, all the repops have the 2" neck anyway. Which is why I began wondering, is it even worth messing with this EEC stuff and I'd be better off just getting the older style tank and calling it a day?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I just ordered an in cab tank through Autozone. No shipping.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Interested to see responses here. Haven’t decided whether I want to go in cab on my K10 or not. Keeping it pretty original so I might....

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

davischevy, do you know if yours is a spectra?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I am not sure. I was impressed with the finish. I did have to change the fuel cap.

The thing about buying through a local parts store, you can send it back if no satisfied.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I'm pretty sure it is a Spectra, but only pretty sure.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

This thread is 4 years old. so maybe someone started but no one at the time made a correct 72 EEC tank. GMCPaul still doesn't carry one, so I'd assume one isn't made.

http://67-72chevytrucks.com/vboard/s...3&postcount=13

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I have a stock EEC system in my truck, I’ll take a picture of it after work tomorrow and post them.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Replaced my 70 tank with one from a 72. I might want to go with a ls sometime and this will give me a return line option. Was a Key tank from J.C. Whitney fit is like factory. The first tank was damaged in shipment that shows in the pics. I think it was 160 shipped to the door.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Run all the vent tubes. Like stock then when it comes to the canister just delete it. Add a filter to the end of the main vent hose that runs to the canister and get rid of all the vacuum lines. Never had a problem.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

69Tom - Yeah, I saw that thread too...and I was like here we go, nothing is ever as simple as it should be!

SRU1436 - That would be super helpful! Mine has an open, uncapped line that terminates underneath inside the frame rail on the passenger side close to the bottom or the radiator/battery box. I had been wondering what it was for. I am guessing it is reminiscent of the old canister.

OL Skool - Your tank looks like it fits like a glove. That's what I'm after. I don't plan on doing an LS swap, so I'm staying traditional.

71GMCC15 - Is that what you did with yours or are you recommending that approach?

It appears that my current tank has the wrong cap on it, and there's no canister. It only has a 2 line fuel pump too. The EEC trucks had a 3 line fuel pump correct? I'd like to just follow the path of least resistance in getting a new tank in here. I don't particularly care if the truck is EEC or not as long as it works right and I don't have to make any custom modifications...

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

That what was already done to mine. The canister was still there but the bottom was blown out. So I just put a filter on one house that was still there and called it a day.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

No kidding. I'm glad you posted this. I just got a 72 and only had earlier trucks prior to this so I was all set to chuck my original tank and just buy a new one. After reading through numerous threads on the subject, I think I'm going to take my tank to the local radiator shop and have them hot tank it to clean it out and see where I'm at at that point. Mine is a SoCal desert truck, so if it wasn't lacking a cap for god knows how long, there'd probably be nothing too wrong with it.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Does yours still have canister?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I don't blame you for trying to save the original tank. I tried to save the one I just replaced. I put a bunch of time and money into it. All seemed well, then I took it for a drive and started smelling gas fumes. It had developed a pinhole on the back side.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Since my system is incomplete and I don't plan on completing it, it's basically going to operate as a pre-'71 in function...I'm thinking I have 2 options.

1) Replace with an EEC tank but it leave it kinda of 'unhooked' and use an old style gas cap.

2) Replace with a non-EEC tank which might be a little cleaner/simpler?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Gas caps are different between a 1971 and a 1972.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Right, but mine has got a cheapo, pre-72 on it already, and gas caps are cheap anyway.

bah someone tell what they would do if they were in my shoes I can't make a decision

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Here is my canister on my 72 c10. It’s a California truck.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Interesting. Thanks sru1436. I bought my truck out of Oregon but don't know if it's whole life was spent there or not. Does your truck have 3 lines coming out of the fuel pump?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Yes. The second photo is the three lines coming from inside the cab

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Thank you very much for those pics. That is very helpful. Looks like me EEC system is missing most of the parts. I've got a spare line that runs inside the passenger frame rail, but thats it.

I'm leaning towards just going non EEC tank. If I switch to the older style tank, Do you think I'll have to cut my old EEC line off where it goes into the cab/tank or can I just leave it in place, defunct? I'm assuming it wouldn't interfere with anything...

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

You’re welcome

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I have an EEC tank but I don't have 3 lines in the floor of the cab. I have 2. I have 1 fuel line and 1 vapor line. Does anyone know about these 3 lines?

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I just put a new tank in my 68 C10. Original truck so it is just a straight tank never had the canister or vent lines.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I read through this old thread and most of the information is pure bologny and false, erroneous information.. The fuel pump has nothing to do with the EEC system. They are two totally separate systems not connected together in any way..

Starting at the fuel pump, there are 2 variations.. One pump has 2 connections - the rubber line coming from the sending unit in the tank, which is the pump suction line. This line draws fuel out of the tank. The other fitting (a flare type fitting) on the pump is connected to the line that delivers fuel to the carburetor. If you have only one line connection on the sending unit, this is probably the fuel delivery system you have.

The other fuel pump has 3 connections.. Two of the connections work as described above. The 3rd connection is a 1/4" nipple. it serves as a fuel return through a line back to the tank. This recirculation serves to keep fuel moving at a faster rate to help prevent vapor lock. This line runs basically parallel to the suction line all the way back to the tank sending unit.

The EEC system is a fuel vapor only system.. There is a nipple on the gas tank in the upper corner on the passenger side of the tank.. This nipple has a rubber hose connecting to a steel pipe that runs up through the B pillar and back down through the floor in the area where the liquid fuel lines pass through the floor. This line continues along the frame rail to the front and connects to the charcoal cannister located under the battery. Coming off the canister are 2 more vacuum lines connecting to vacuum control pieces on the engine.

The simple facts are:
#1- If you have 3 connections on the fuel pump and 2 on the sending unit, you have fuel recirculation plumbing..

#2- If you have that nipple on the upper passenger side of the tank, you have an EEC system. If the EEC system components are in place and working, you will need a non-vented gas cap for the system to properly function.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Good stuff.

If you go by the parts book the recirculated system was installed beginning in 1972ish. I say ish because you know, sometimes they installed new stuff before the next year, sometimes even old stuff from the former year.

You say it has nothing to do with one another, fuel/vapor. Tell that to my former mechanic:lol: After the canister and that were pulled he connected the vent line to where a return line would be on the fuel pump replacement. It worked somehow, couldn't tell you, though the replacement cap was vented.

You know what else is BS is vendors sell upper fuel lines varied on whether or not the truck has A/C. It has nothing to do with A/C, some people suggest it does. The difference is whether or not the fuel pump takes a return line. They figure a return line means it's A/C equipped:metal:

Here's a tank assembly for an EEC system for reference. Images of the two different fuel pumps too.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

There is a difference between stupid and ignorant.. Ignorant is simply a lack of knowledge.. A little education and the problem is solved...

Now stupid is a horse of a different color.. Stupid can't, or won't, learn... They do things just because they can, not because they should. You'll have to tell that to your former mechanic yourself.. I never make any attempts to teach the stupid.. :):)

You are a wise man to have made him your "former mechanic"... :cong:

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Words of wisdom. Agree, personally I like being corrected and tuned. I'm world champion for questions, and too many times I think something is fact when it's not at all. It's an education when you're open to it, and hopefully learn to hold things at bay till proven.

He was actually a good mechanic for the most part. I think meth did him in. He took over the old man's shop, and that old man was excellent. I used them because I knew nothing about these and mechanical beyond simple, and shied away from it.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

'
I'm quite elderly and retired now, but I was a mechanic for some 30 plus years. Twelve of those years I was a shop owner. I would never do a hack job on any car in my shop or work space, even if the customer only wanted it done that way. I have ethics and a penchant for honesty. I had a good reputation and was rewarded very well for my efforts. I put both my kids through college. One is a loan officer at a lending institute and the other is a safety engineer at the worlds largest petroleum refinery.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

You don't realize just how fitting that photo/meme is to me.. Check the cover photo on my facebook page and you'll see why..

https://www.facebook.com/nick.gans.96

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I believe the third line was for an A/C truck and was a fuel pump by-pass return line to help prevent vapor lock.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Irony is awesome. Same that farm, thank you. Texas must be neat, seems of the folks are handy and talented. I like how many can string words together & wit that comes with it. Nice B-day present, she must be a peach.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

That's what I've heard, but I rebuilt this 71 a/c without it, because i'm 99% sure it didn't have a return. Hopefully it won't vapor lock, :lol: Gross:smoke::metal:

I believe this truck didn't have a return line because of memory, and how I found the truck when I tore her down. It's a numbers match original 402 A/C. I've had it since 89, the original owner was an old man who primarily left the truck alone.

A return line for example requires different tube retainer clips. This truck has them for 2 & 3 tubes where a return needs them for 3 & 4 tubes.

Additionally, if you look at the parts book, and if we're to assume it's correct and representing, the 71 took the shorter fuel pump (no return) and the single line fuel sender too. Regardless of A/C, it's straight forward.

If memory serves me right, the part's book calls for a return line for turbo hydramatic transmissions. Couldn't tell you why. Beginning in 1972. 71 takes a different fuel cap than 72 as well. Seems the 70 is the same as a 71.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Oh, she's a peach alright.. We met a little over 60 years ago when she was 14 and I was a college student. We celebrated our 56th wedding anniversary this past October.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

I believe the automatic trucks had three lines. Supply, return and the EEC vent. The manual trucks had two lines. Supply and EEC vent. Ive read somewhere the return line was to help with vapor lock issues.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

No:lol:

If we assume GM's parts book doesn't lie on the subject, and I don't believe it does in this case, return lines were installed beginning in 72, not to say late model 71 wouldn't have one. My 71 A/C 402/400TH didn't have a return line. The pick-up is one line and the pump the same. More confirmation is my retainers took no more than three lines (brakes, vapor, gas). Some of the retainers take four with a return.

But seems you're right about automatics, at least some. I know a 72 with a TH transmission calls for a return line. You may be right about vapor lock too, perhaps more prone with A/C on? My truck has never vapor locked, knock on wood.

Re: Let's Talk about In-Cab Reproduction Gas Tanks and EEC vs non-EEC
 

Thanks for all of this info!! Just to clarify, if I have all of #2 but NOT all the components of the charcoal canister but just a line going to the front through the frame rail with a filter on the end to “cap” it off, then is a vented gas cap ok ?