Blazer Tank Swap

[Russell]

Hey guys!

I'm sure a couple of you fellas have done this swap already, so I thought I'd get some advice before I dove into my fuel tank swap.

First off, the placement of the crossmembers -- Is there any science to this, or do put the rear crossmember in, bolt it up, put the fuel tank up with a couple jacks and put the next one on, or is there a different procedure?

Second off, would there be a problem with running a homemade filler hose out of exhaust pipe that'll run along the inside of the frame rail to the stock gas door?

Finally, would it be safe to run rubber fuel lines from the fuel tank to the fuel pump, or should I run with metal compression fittings the whole way?

[bigblock73]

Here is Chris' article on the Blazer tank he put in Su...

http://www.captkaoscustoms.com/blazertank.html

[Russell]

Thanks Jeff!

I'm gonna see if I can make stuff work with the factory brackets, if not, I'll do what the Capt. did with the angle iron up front.

[Captkaos]

The factory Blazer mounting stuff wouldn't work under the pickup for me, it would hit the rear of the pumpkin. Mine is REALLY close as of now. Since you are going EFI, I would use braided line like the factory used. Just my opinion.

[Jonboy]

is there more room behind the axle on a long bed? If so, Russell should be in the clear.

[Russell]

Originally Posted by Jonboy

is there more room behind the axle on a long bed? If so, Russell should be in the clear.

Not sure, I'd guess that the frames would be the same from the wheel wells back, so that may be an issue, we'll see. The only things I am gonna be doing different is put some spacers in so I don't have to notch my bed crossmembers, there are more in the way with my longbed than there would be with a shortbed and use the factor rear frame crossmember. I'm gonna get a couple buddies over tonight to pull my box off again so I can get started on the swap. I need to park the truck for a couple weeks to save gas money anyways. As far as the fuel lines go, it'll be a solid fuel line from the fuel pump all the way up to the front of the frame, I just need to figure out what type of fuel line I need between the fuel tank and the fuel pump (will only be a few inches, I plan to mount the pump on top of the tank)

[Jonboy]

If you get the tank from the wreckers, try to get as much of the fuel lines as you can. An 87-up Burb tank would be ideal for what you are doing, as it would be baffled and have the correct pickup and all for the TPI swap. FWIW, an 87 fuel tank from a pickup would work perfectly too, but would bolt right up.

[Russell]

Burb tanks are too long, you'd have serious clearance issues with the rear diff. Thats one of the first things I checked I got all of the fuel lines from the tank up to the front of the K-5, so no worries with pipe. I need to borrow a pipe straightener / bender though, so I can do some customizing with the lines. An 87+ blazer tank would have been best, but a blazer is hard enough to find as it is, so I can't really choose, lol

[Jonboy]

I think you will need the baffles in the 87 and later tanks for the EFI, to keep fuel from running away from the pickup. Have you checked into aftermarket tanks? They are about $100 or so down here, and about that in the LMC catalog. There is a section in the JTR manual about modifying your tank for EFI, but I am not a particularly big fan of welding on a fuel tank.

[Captkaos]

Originally Posted by Jonboy

is there more room behind the axle on a long bed? If so, Russell should be in the clear.

DUH! Yes there is...
BTW, the "normal" 27gal gas tanks for Burb are the exact tank that a K5 uses.

Russell
You have to use EFI spec. rubber hose where you aren't using hardline. I am sure you knew this, just verifying since you said you were trying to find out what you wanted to use.

[Russell]

Originally Posted by Captkaos

DUH! Yes there is...
BTW, the "normal" 27gal gas tanks for Burb are the exact tank that a K5 uses.

Russell
You have to use EFI spec. rubber hose where you aren't using hardline. I am sure you knew this, just verifying since you said you were trying to find out what you wanted to use.

Then my buddy doesn't have a normal burb tank, it woulda had about 3 inches of tank above the rear axle on my truck. I know I need 250 + PSI rated fuel line, just trying to decide where I want to run with rubber, and where I want to go with steel lines, basically what I need to figure out is if I want to hack tank's fuel line ports to go with hard line, or if I want to run with a rubber line from the tank to the fuel pump / hard return line.

[SanitysBane]

don't use a an intake fuel pump on a vehicle that had TBI, thats only about 7psi, not anywere near enough for TPI, i've got an 88 sending unit and fuel in my truck that i had to cut down about 1 3/4 so it would fit, and with a carb, it doesn't matter to much if the pump sucks fuel. also the 88 trucks have nice pretty braided steel flex line too

[Captkaos]

Originally Posted by Russell

Then my buddy doesn't have a normal burb tank, it woulda had about 3 inches of tank above the rear axle on my truck. I know I need 250 + PSI rated fuel line, just trying to decide where I want to run with rubber, and where I want to go with steel lines, basically what I need to figure out is if I want to hack tank's fuel line ports to go with hard line, or if I want to run with a rubber line from the tank to the fuel pump / hard return line.

It is probably the 41 gal version. You want rubber line anywhere you cross to a potential flex point. ie: frame to tank. Frame to engine/trans.

[Russell]

Alright, thats what I was looking for.

I tore the box off today, thats a real work out doing it by yourself!

Tommorow I'll mount the rear bracket, and decide what is gonna happen with the front bracket.

[bluex]

Originally Posted by Jonboy

is there more room behind the axle on a long bed? If so, Russell should be in the clear.

Yes there is about 4.5" more after the rear tires on a long bed.

[Russell]

Alright, I got into this project after sickness and homework have delayed me for almost a week... I got my rear bracket mounted, and the rear-most frame crossmember removed. As far as I can see, I will only need to remove one more crossmember and be able to leave my brake line mount attached. My electric fuel pump also arrived, so I can get started on my fuel lines right away too. My only worry now is if my plan to use the front filler door and route the fuel using exhaust pipe is a bad one, what do you guys think?

[Russell]

I got my front bracket installed, I won't need to touch my brake line mount I'm still gonna want to remove my old unused factory exhaust bracket, and I need to remove the middle frame bracket. I'm also gonna install some angle iron spacers, so I'll have four more holes to drill for them, otherwise I'm nearly done the tank install. I still need to figure out how I am gonna plumb my filler neck, and I still need to plumb my fuel lines from the tank to the pump to the location of my old fuel lines. Gonna be using compression fittings on the steel line the whole way up from the fuel pump, and rubber EFI fuel hose rated for 250 PSI from the tank to the pump, and for the return line. I'll worry about the front fuel lines later.

Tommorow I'll post pictures This whole blazer tank is a bolt up upgrade for a longbed truck, sure is a pain in the butt to drill all those holes though...

[SanitysBane]

i got mad at my truck for taking so long to fill up so i cut a whole in the bed floor and ran the filler neck right out of bed floor, fills up great now!

[Russell]

Well, I got my tank mounted today -- I ended up discovering why most guys make their own front bracket, my tank sits about 2" above the framerails (dome on top of the tank and fuel inlet / outets included in that 2") so I'm gonna have to cut the two crossmembers under my bed by 2" for about 28" across, should be fairly easy work with my acetylene torch. I would have had to have done this regardless of if I intended to or not, I wanted / need to use the skid plate as I broke one of my tank hold up straps, so I don't trust the second one. While mounting the skid plate I discovered that it tightens the tank up against the crossmembers I installed just as tight as the straps ever could, so I tightened the one strap and mounted the skid plate. I also discovered upon my first attempt to lift the tank into place that I had my front crossmember back too far, so I ended up moving it forwards, but as I started drilling the second hole on each side, I broke my bit, so ended up only putting 4 bolts onto the front crossmember. Still more than the original and the skid plate helps move some of the weight to the back, so I feel it'll hold just fine, esspecially considering all the bolts I've used are 1/2. I also installed my return line and attached it to my factory return line under the cab. The fuel pump I have right now doesn't have a return line port, so no worries about my fuel pump filling my blazer tank while I drive it over the next couple weeks.

Tommmorow I need to plumb up my supply line / fuel pump, and finish hooking up the sending unit wire. After I get my fuel pump plumbed in, and my bed notched, I'll be ready to put my box back on, and start doing some of my first body work, putting my truck's third gas door on at the back. After much hmming and hawing, I decided I'll just try putting in the fuel door, If it works good, I'll do it to my new bed as well, if it doesn't, I'll get a body shop to help me out.

Its all getting there, I'll post a couple of pictures from tonight after I resize them here...

[Russell]

Here are two pictures, I didn't take very many becuase it was dark in the shop by the time I got around to taking pictures, and when I take dark pictures, it makes stuff look rustier than it actually is, lol

[Russell]

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