The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Calling everybody that has switched out a gas tank on a 73-87

tucsonjwt · 10-04-2012, 05:46 PM

Good point on not using a metal screwdriver. A piece of hardwood like oak or maple will work.

If your sending unit is working just reinstall it. You might need to replace the o ring - just a few dollars at any parts store. Be extra careful taking that sending unit out of the tank and re installing it. It has fragile parts on it and a nylon sock on the end. If the sock is shot you can get a replacement.

I forgot about unscrewing the fuel inlet hoses prior to tank removal. I have a dump conversion so my fuel inlet hoses are just sitting there not hooked to the bedside.

When you take the short hoses off between the sending unit and the hard lines you can take those hoses to the parts store when you pick up a new o ring and just have the store clerk measure them up. Depending on your truck, I think you have 3/8", 5/16", and 1/4" hoses etc. As I said, the best bet is to measure the outside diameter of the sending unit nipples, but you can just match them up at the parts store - they do this all day at the store. The only issue is if the hoses are ballooned out of shape you have to guess at the true diameter. If your new o ring does not fit well, just clean up the old one and re install it. The aftermarket o rings seem to be extra fat and don't fit well in the factory recess.

10-04-2012, 05:46 PM	#22
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Calling everybody that has switched out a gas tank on a 73-87 Good point on not using a metal screwdriver. A piece of hardwood like oak or maple will work. If your sending unit is working just reinstall it. You might need to replace the o ring - just a few dollars at any parts store. Be extra careful taking that sending unit out of the tank and re installing it. It has fragile parts on it and a nylon sock on the end. If the sock is shot you can get a replacement. I forgot about unscrewing the fuel inlet hoses prior to tank removal. I have a dump conversion so my fuel inlet hoses are just sitting there not hooked to the bedside. When you take the short hoses off between the sending unit and the hard lines you can take those hoses to the parts store when you pick up a new o ring and just have the store clerk measure them up. Depending on your truck, I think you have 3/8", 5/16", and 1/4" hoses etc. As I said, the best bet is to measure the outside diameter of the sending unit nipples, but you can just match them up at the parts store - they do this all day at the store. The only issue is if the hoses are ballooned out of shape you have to guess at the true diameter. If your new o ring does not fit well, just clean up the old one and re install it. The aftermarket o rings seem to be extra fat and don't fit well in the factory recess.