Sender unit safe to pull?

[jpalmer1717]

My fuel guage reads 3/4 and up correctly, but never drops below 3/4. I'd like to pull the sender/pump unit and hopefully fix the float one way or another. I started the process, but could not remove the hoses after sliding the hose clamps off. So I am wondering if it's safe in general to take this little project on, and how to get the extremely tight hoses off. Or should I just take it to a local mechanic which so far I have avoided. Thanks for any advice!

[Meanmyz]

I will be tackling this project this winter and hope to gain a little knowledge that I can pass on then. I am mechanically inclined and have an idea of what to expect. It is just that I haven't done this project before. In my initial research, I think I have found some places that will refurbish the sending unit at a good cost savings over trying to find and buy new parts.. It may not be the float at all. If you wait, maybe I will have some points to offer. While you are in there, Carter, here on this forum, has a part in the assembly, that he makes as an upgrade.

If you loosen the clamps, I am sure a needle nose pliers working just past the end of where the hose is slid on, will break its hold on the pipe end.

The double clamped hose sends fuel to the engine. The other is the return. I would buy a new rubber tank gasket and have on hand when putting back together before you start taking apart .

[ZWILD1]

I replaced the fuel pumps in my first ZR1. As I recall what I did was use a pair of pliers to first loosen the lines by moving the pliers back and forth around the rubber line where it fits over the metal line. Then once loose I could work them off. But if those lines are showing signs of cracking or rot you should just replace them. If so you can use a blade to carefully split the ends but not scar the metal lines.

[Flyman 27]

I would use a 90 degree "pick" tool to slip in between the hose & steel tube, then work it around. You will want to install new fuel hose and clamps. I got German clamps from Amazon, didn't want to install Chinese clamps.
Mark H told me that he commonly removes the cover to the sending unit & cleans off the resister coil with a scotch brite pad. This usually works for him.
The R&R is an easy DIY job, just get a new gasket first like recommended above.

[Meanmyz]

I would use a 90 degree "pick" tool to slip in between the hose & steel tube, then work it around.

That was such a good answer, I wish I had suggested it!

[jpalmer1717]

Thank you so much for the great advice. Gasket is ordered and pic tool too!

[WARP TEN]

I would use a 90 degree "pick" tool to slip in between the hose & steel tube, then work it around. You will want to install new fuel hose and clamps. I got German clamps from Amazon, didn't want to install Chinese clamps.
Mark H told me that he commonly removes the cover to the sending unit & cleans off the resister coil with a scotch brite pad. This usually works for him.
The R&R is an easy DIY job, just get a new gasket first like recommended above.

Picks are great to have when you need them. I got a set of regular heavy duty picks a while back and keep them in my tool chest. They are great when I can't otherwise get to something. But when working with smaller things, like my Lionel trains, I need smaller picks, so your note prompted me into action. I just ordered a set of dentist's picks off Amazon for about $12, a slightly better set than the one for $8 but it probably would have worked too. I am sure that when I get in to my annual winter maintenance on the Lionels I will make use of them, and who knows for what else. For the price it seems like a useful item to have just in case. Thanks George--Bob

[Flyman 27]

I have & use the dental picks as well, they are cheap and useful.
I also have the picks in the small & medium sizes. They really came in handy when we dismantled & reassembled my steering column, for the little clips on the main shaft.
The picks are also available in a larger size, about 15-16" long. But I just can't figure out what they would be good for.

[mhobtr]

I use channel lock pliers to rotate the hose slightly before trying to pull it off. You don't need much pressure and all you want to do is break the sticky area under the hose clamp hose loose from the metal pipe.

On the fuel tank connections, I have had better results pushing them off rather than pulling. I use a plastic pry tool for this.

If all else fails, I go to a 90 degree pick.

[jpalmer1717]

Does anyone know where I can find a diagram of the sender unit? There's a decent chance I will pull it out and common sense will kick in and tell me what the problem is...but I thought maybe while I'm waiting for the new gasket to arrive, I'd start studying the part itself. I can find info on non-ZR1 sender units on Youtube, etc, but I'm not clear on the difference with the ZR1 unit.

[Flyman 27]

The standard C4 sender unit holds 1 fuel pump.
The ZR-1 holds 2 fuel pumps.

[Perry Mitchell]

If it was a picture of a sending unit you wanted, here is a couple from a 91 ZR-1. The unit is available.

[jpalmer1717]

How much $$?