How I Fixed Fuel Sender Binding Problem in 88 Tank (Page 4/4)
V8Steve JAN 19, 09:46 AM
That's a great idea! Wish I'd thought of that.

Given the amount of labor messing around with solving any kind of fuel tank problem, maybe the split float is a safe choice. You can buy replacement floats online so, if the size was right, that might be another solution as well.

I remember doing a lot of bending to solve it and I seem to remember I bent it at least a 1/4" away from that side baffle with no improvement.
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88GT 355 CI Sequential Holley HP Multiport EFI, AFR milled 180, Dyno'd at 427 HP, 320 WHP, F40 6-Spd
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[This message has been edited by V8Steve (edited 01-19-2021).]

Dennis LaGrua JAN 19, 03:19 PM

quote
Originally posted by V8Steve:

That's a great idea! Wish I'd thought of that.

Given the amount of labor messing around with solving any kind of fuel tank problem, maybe the split float is a safe choice. You can buy replacement floats online so, if the size was right, that might be another solution as well.

I remember doing a lot of bending to solve it and I seem to remember I bent it at least a 1/4" away from that side baffle with no improvement.


Good info but you are saying that shortening the float 1/4" may not work. I'd have to believe a 1/2" cut would probably do it but it may not. All you need is to have enough buoyancy to float the rod at the top of the gasoline level. I guess that I'll do the cut and weld of the split float and play it safe. It just pains me to think that I'd have to do this on a brand new part.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
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Larryinkc JAN 19, 05:20 PM
I put one in my 88 Mera several years ago. I had the same problem with the float hitting the baffle. I called The Fiero Store and they were aware of the problem and told me to bend the sheet metal mounting plate where it is spot welded to the metal fuel line. I was concerned that bending it would break the welds, they assured me that it wouldn't. I don't remember exactly what method I used to bend the plate but the welds held and it works great. I have had it out to change the fuel pump and all is still good. On that thought I will only use a genuine Walbro pump bought directly from Walbro in the future, you won't get a knockoff from them. They are a bit noisier but are very reliable fuel pumps.

[This message has been edited by Larryinkc (edited 01-19-2021).]

V8Steve JAN 23, 01:08 PM
UPDATE
My modification to Archie's float ended up with a problem. The Fiero Store unit was binding on the passenger side of the tank. When I made up the paint roller modification for Archie, it didn't quite come out on the center of the rod and the binding moved to the driver side. For reasons beyond this thread, Archie was able to remedy this and keep moving.

My own split float worked immediately but there is a word of caution here. Today I took out my cutaway tank again and measured the inside dimension between the two baffles at the EMPTY position. It's around 4-3/8". The Fiero Store float plus an allowance at each end for the rod makes the overall length around 2-7/8" - 3", resulting in a total clearance of 1-3/8". I seems like a lot but the clearance at EMPTY is critical and depends on where the rod is. The position of the rod depends on the location of the wiper as welded to the return tube. So, in Archie's case we ended up with binding right wehre the tape measure shows the 4-3/8". Above that, the same driver side baffle practically disappears and opens up a huge space. This would result in a float that moves freely when full but won't freely descend to EMPTY.




So, this tells me there is a chance the equally split float might still have issues that might vary from one assembly to another. The way to solve that would be to attach the cross piece and make it around 3-1/4" long and centered on the rod. Weld it in place. DO NOT CUT THE FLOAT YET. Then put it back in the tank with the correct Delco seal and check the ohms at empty and upside down full. (If you take the easy way and assemble without the seal, the results may be inaccurate). If the ohms are too high on empty, trim the float axle back until the EMPTY ohms are OK. If it's binding on returning from FULL, you know the opposite side needs trimming. Eventually, the float rod will go up and down freely.

Once you reach that point, it's time to carefully note if the float axle is centered or if you removed more material from one side than the other. Then make sure each side is long enough to hold a portion of the float along with the locking push on washer. Cut the float to fit the respective dimensions on the axle and assemble. Check one last time before installing in the car. I connect the harness to the chassis harness before actually installing the tank just be sure the dash gauge is working. Put a gallon of gas in the tank first for the final check.
RCR JAN 24, 08:55 AM
Great writeup, Steve. Gave you a plus.. Figures my tank is full, but this might explain why my gage stopped working.


quote
Originally posted by Archie:
I'll be installing this as soon as it gets back here.
Hopefully by then I'll figure out how to get PIP working for me again.
Thanks
Archie



Archie... You don't need PIP. There is an image upload button now....

Bob
DrXtreme JAN 31, 11:44 AM
Does anyone else have a wire tapped into Purple sending unit wire? Found it when I dropped my tank (no plug to disconnect of course) and it goes somewhere up towards the engine.

Its a very thin wire, will try to trace it thinking its for low fuel warning in Caddy since its N* motor?
DrXtreme JAN 31, 08:33 PM
So I discovered the previous owner purchased the Fiero store tank line assembly. Of course they used the regular fuel line hose in the tank, so when I poked it with a screw driver it was soft and only a matter of time before it let go. I too had fuel sender issues; read full down to 66%, float hanging up on passenger side baffle.

So after reading this thread, I took needle nose pliers and bent the plate holding the sending unit and float to move it more center of the tank. You can see in the pictures the float is right of center, so I moved it left of center. Tried it 2 different times and gives the full and empty readings on the ohm meter.

Waiting on submersible hose to connect new pump. Then install, check gasket for leaks and double check float operation. Hope this helps others.

Dr Xtreme [img]http://images.fieroforum.com/userimages/DrXtreme/Float%20mod%20 2.jpg[/img]