V8 or I6 Fuel Tank Sending Unit

[Legolas894]

I need to buy a new sending unit (the little resistance wire is fried). I know it's 90ohm but when I look in the LMC catalog, they have one for 2BBL and one for 4BBL. In Classic Trucks, they have one for 6 cyl and another for 8.

My truck had a six in it from the factory but has a 283 in it now with a quadrajet carb. Is it a fitting size thing? How can you tell which sending unit will work.

Thanks,

[cdowns]

6cyl outlets r 5/16 and 8cyl r 3/8

[Longhorn Man]

inline 6 is 5/16ths
2 bbl small blocks were 5/16ths
4 bbl small locks were 3/8ths
big blocks were 3/8ths
GMC only;
v6 trucks 3/8ths

[Legolas894]

Ok-Forgive my ignorance but is it he size of the wrench that fits on the fitting or the size of the pipe?

Thanks a lot Cdowns and LH Man!

[Blazer1970]

Originally Posted by Legolas894

Ok-Forgive my ignorance but is it he size of the wrench that fits on the fitting or the size of the pipe?

Thanks a lot Cdowns and LH Man!

It is the size of the tubing that is used for the lines. The smaller 5/16" tubing has been known to starve a healthy V8 for fuel.

[Legolas894]

Thanks-I should have known that answer but I always get confused with what "size" fittings, nuts, bolts, washers etc are. They almost never seem to be the size you could actually measure with a caliper or tape. I think it's even different between "tube" fitting and NPT! Probably a conspiracy to sell more parts and tools! In Canada, we all have to have both sets of wrenches (SAE and Metric).

[BurnoutNova]

Originally Posted by Legolas894

In Canada, we all have to have both sets of wrenches (SAE and Metric).

Unfortunately thats the same way here in the U.S. The Snap-On and Mac guys that come to my work takes full advantage of that. I especially love when I have to buy SAE, Metric, 6 point, 12 point, E torx, regular torx, tamper proof torx, Hex drive, and Tripple square sockets. I wish it stopped there but thats not even it!