I have a choice between 2- not sure which one to order for my 67 Olds 330 2 barrel.

SPECTRA PREMIUM Part # FG88C Includes Fuel Sender, Float and Strainer (Fuel Pump Not Included); 0-35 Ohms
Exc. Station Wagon; 5/16" Outlet

SPECTRA PREMIUM Part # FG88D Includes Fuel Sender, Float and Strainer (Fuel Pump Not Included); 0-95 Ohms
Exc. Station Wagon; 3/8" Outlet

 

you need to figure out what you are running currently the ohms difference is way to far off gauge will never read right 5/16 is small block 3/8 is big block does yours have a return as well some are two line some are three

 

I have the '67 chassis service manual (I have a '67 Delta), and in the section on troubleshooting the fuel gauge, it says that the resistance of the sending unit should vary between 0 and 90 ohms. This is for all series, Cutlasses as well as the big cars. You want the second one.


I'm actually kind of curious what cars the 35-ohm unit is intended for. Not that I've heard of a lot of them, but I've never heard of a sending unit from that era that DIDN'T operate over the 0-90 ohm range.

 

many thanks.

 

You're welcome. Now watch, you'll buy the 90-ohm one, and it will turn out to be the wrong one. Remember, all my advice comes as is/where is. No returns. All sales final!

 

Your fuel line (from the tank to the pump) is either 5/16" or 3/8". Find out which it is and choose the sending unit to match it.

Norm

 

Not in all cases.

I don't know if it's the case for the Cutlasses, but on my '67 Delta, the fuel line is not metal all the way from the tank to the fuel pump. There is a short (about 3-foot) rubber section that connects to the sending unit outlet at the tank at one end and goes over the rear axle and connects at the other end to a steel line that then goes to the fuel pump. If this is the case for his car, then does it really matter what the outlet line diameter is if all he's going to do is slip a rubber hose over it and tighten a hose clamp?

I would think that having the proper resistance would be the key factor, because if he has the wrong one, his dash gauge will not read properly. If he puts the 35 ohm unit in, and he's supposed to have a 90-ohm, the gauge will read empty when the tank is empty just fine, but when his tank is full, the gauge will only be pointing at the 1/3 mark.

 

Follow up:

I checked the '67 chassis service manual, and, like the big cars, the Cutlasses did use a short length of flexible hose between the end of the fuel tank outlet and the start of the steel line on the other side of the rear axle.

I also found that the Cutlasses did use two different fuel tank units, depending on which engine was in the car. 400 cubic inch engine cars used a two-line sending unit where the second one was a fuel return line. Cars equipped with the 330 used only a single-line sending unit.

Both of the units that Bottoms mentions in the first post are single-line units. Again, I think he needs to go with the 90-ohm unit as that resistance value is the only one mentioned in the manual.

One nice thing about your car is that you can remove the sending unit without dropping the tank. That's a HUGE advantage over my '67 Delta, where the sending unit is on top of the tank, rather than on the side. That's makes it a bit more bearable if you have to get under there to change the sending unit twice!

 

A little mismatch between a rubber hose and hard tube in a fuel system might never leak, but it is not the kind of work I do.

I would think that the diameter of the line would match the gauge in the car, as well as the existing sender.

Norm

 

Of course it isn't. We would be disappointed if it was.

 

So I pulled the tank and indeed the sending unit outlet is 3/8th. A new Spectra tank and sending unit is on the way- the old tank sounds like it's filled with BB's. Is the fuel pump something i should replace as well- does fuel sit in it normally when not running? (worried that that may be gummed up). I plan on rebuilding the carb and replacing the 2 sections of rubber fuel line. So in the end the entire fuel system should be pretty much new with the exception of the old hard lines which I'm hoping I can clear with compressed air. Am I forgetting anything? Thanks

 

I don't know. I've never replaced one. I would probably go by the car itself. Was it running before you started all this? If so, the pump's probably ok. If not, or if you don't know, heck, you're replacing everything else, so might as well throw one of these on, too.

 

The car last ran in 96'. My father had a full tune up done and then parked it. So it was running good then- but that was a long time ago.

 

I ain't no expert, but if the car ran fine when last parked, try starting it without replacing the fuel pump. You'll probably be fine. If you're concerned at all, perhaps you could take it out and clean it up. Run some fresh gas through it.

 

So much for my impression of a diplomat.

To be a little less delicate: It is a move that only a schlock would consider.

Norm