I have a '73 Blazer. Just installed a 454 from a 3/4 ton chevy truck. Had some vapor lock issues, and now I want to install a return line to my original tank. I dropped the tank today, expecting to see the 3 outlets. I removed the sending unit, and noticed that the inside of the tank is dirty, and the sock is tore at the end. How do I proceed form here? I am having a hard time finding a 4 outlet sending unit for a '73 blazer tank. Am I stuck with modifying a new 3 outlet unit? Help! I want to drive this thing before the weather gets nasty.
CK5
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Fu;el tank and sending unit questions...Help!
- Thread starter rman45
- Start date
You can buy a new sock at any parts store. As for a return line I would drill a hole in the sender and then cut a proper length of steel fuel line and run it through the hole and get it as close to the pick-up sock as you can while at the same time making sure it doesn't interfere with the float then silver solder that steel fuel line to the sender. I did this years ago when I installed TPI on an old blazer project.
I just replaced my tank, fuel lines and sender recently. Also rebuild the carb and replaced the fuel pump.
I bought an aftermarket Spectra but it was not the correct fuel line size for my 78. GM changed the fuel line size at some year. What size is yours? If you want my 4 line sender let me know. I have no need for it and would sell it to you. I also have compression clamps for the fuel hose if you need those.
For steel lines go with Inline Tube. You will need the return line. You could also use fuel hose but I prefer steel line.
Get a new tank from Rock Auto. The Spectra premium is made in Canada and looked better then OEM. They had it stamped made in canada on the tank. For only something like $120 it was a great deal. MTS sells plastic tanks but i prefered the steel. Spectra coats the tank with some zinc material and they also have nice welds.
My fuel line is a 3/8 hose. I think the return line is 5/16 or 1/4" . Let me know if your will work. I would assume they need to be the same depth. I'll get a measurement this afternoon.
Thanks.
Thanks.
So here's what I did to resolve my vapor lock issues:
1. Added electric fuel pump and filter near the fuel tank that supplements mechanical pump 1-4 lbs. This will add pressure to the fuel between the tank and the mechanical pump, lowering the boiling point of the fuel.
2. Installed a Mallory fuel pressure regulator with gauge and bypass ports just before the carb. Russell oil filled gauge works great and good looking. Currently adjusted to 5.8 lbs.
3. Installed a fuel return line which runs from the fuel regulator, back down the right side frame rail.
4. Added double layered heat shield with adhesive exhaust wrap that covers from the right side motor mount bracket to about 8" behind rear leaf spring mount on the frame.
5. Modified my 3 port sending unit by adding a 4th port using Russell connecting parts and a 5/16" fuel line which drops just above the filter sock.
I used Russell blue 3/8" twist lock fuel hose from the mech pump to the carb. The twist lock hose is NOT an easy application as they suggest. It's a PITA but looks and performs great.
There doesn't seem to be a lot of complete information regarding vapor lock issues, and I perhaps went a little overboard, but it's an easy diagnosis, and simple to fix. I am curious to find out if this changes fuel mileage. Cooler fuel = performance and?
I hope someone who needs some information finds this helpful.
1. Added electric fuel pump and filter near the fuel tank that supplements mechanical pump 1-4 lbs. This will add pressure to the fuel between the tank and the mechanical pump, lowering the boiling point of the fuel.
2. Installed a Mallory fuel pressure regulator with gauge and bypass ports just before the carb. Russell oil filled gauge works great and good looking. Currently adjusted to 5.8 lbs.
3. Installed a fuel return line which runs from the fuel regulator, back down the right side frame rail.
4. Added double layered heat shield with adhesive exhaust wrap that covers from the right side motor mount bracket to about 8" behind rear leaf spring mount on the frame.
5. Modified my 3 port sending unit by adding a 4th port using Russell connecting parts and a 5/16" fuel line which drops just above the filter sock.
I used Russell blue 3/8" twist lock fuel hose from the mech pump to the carb. The twist lock hose is NOT an easy application as they suggest. It's a PITA but looks and performs great.
There doesn't seem to be a lot of complete information regarding vapor lock issues, and I perhaps went a little overboard, but it's an easy diagnosis, and simple to fix. I am curious to find out if this changes fuel mileage. Cooler fuel = performance and?
I hope someone who needs some information finds this helpful.
