The Stovebolt Site Forums The Shop Area The HiPo Shop 12v conversion fuel sending unit question

I'm doing a 12v conversion and an LS swap is planned for next year...I'm installing a fuel tank from a '94 Fleetwood Limo and obviously it has the 90 Ohm sending unit/fuel pump combo...is it possible to get my current fuel gauge to work with the 90 Ohm sending unit ?

Moved your post (and replies) to the Hi Po forum

The quick answer is "yes".

Click here

Hmmm...ok...yes that does seem to solve the issue (per the product description) but not sure about the install/setup instructions and review(s) aren't favorable.
I assume my options are minimal and looking at custom gauge pricing...not an option at this time.
Hopefully someone else has ran into and solved this before me.

Then try a different brand. Tanks Inc has this one.

A converter of some kind is your best bet if you want to use the stock gauge and stock sender. I built my own, but it was still $30 in parts and a month of work.

Another option that might be cheaper/easier would be to get a universal sender in the right resistance range for your gauge, add it to the new tank, and ignore the one with the wrong range.

Amazon example has one review.........BAD didn't work
The other may be OK but $90. It will also work with your ruduced voltage gauge. BE SURE you tell them what you are doing and get them to say by email it will work before you buy.

The best option, in my book, is leave the stock gauge alone and add a 90 ohm 12V gauge somewhere.

I agree this is the easiest...if only I could find this in the stock gauge format and do a replacement but I haven't found that option

I do see a lot of fairly cheap options for this...but none are a pump/sender combo so I assume that I'd need to cut a new hole in my tank which I'm not a fan of

HRL and some other fabricators will probably vote to impeach me from the forum for this post, but I did a farmer fix on my '57 GMC in 1998 when I installed a mid 80s Mazda B2200 pickup gas tank under the bed behind the rear axle.

Of course the Mazda tank's sending unit didn't match the GM 0 ohms empty, 30 ohms full gauge.

To solve this problem I removed the electrical connection (green circle) from the GMC mounting flange and then cut the pickup tube in two places (red lines) leaving me with the electrics from the GMC. I removed all the electrical bits from the Mazda sending unit leaving just the flange, fuel tube and sock. I used two small screw-type hose clamps (purple) to attach the GMC electric and float assembly to the middle of the Mazda fuel tube and ran the electrical connection through the Mazda mounting flange. The GMC tank was taller than the Mazda tank (needed more movement of the float from full to empty) so I partially straightened out the bends (marked in blue) on the float arm to allow full movement at the GMC float within the Mazda tank.

The tank and sending unit worked fine for 13+ years until some idiot T-boned the truck. In later life I have come to realize that there were two classes I really should have taken in high school, welding and typing.

I applaud your ingenuity...I also just got back from a first fit of the tank and found that my preliminary measurements weren't quite accurate enough (done with the tank still in the donor car and a tape measure...somewhat guessing the edge of the tank) and the tank doesn't fit between the rear springs...lucky for me the tank was free...just the scrapes and cussing getting it out of the donor vehicle...I do have a couple other donor vehicle options to choose from...this one was just the easiest.

You might force a 0 to 30 ohm gauge to "sort of" work with a 0 to 90 ohm sender by using an adapter, but I'll be very surprised if you get a linear output. A variable resistor needs to be constructed to have a certain specific start point and a certain specific end point and a certain sweep arc to be linear. Below you can see where some not very clever worker in China tried to turn a 90 ohm coil into a 30 ohm coil so he could sell it as a 30 ohm sender...and he sort of succeeded---he wiped out enough of it dribbling molten solder on it but there is absolutely no linearity and no accuracy to this mess. Good luck! I'd get a 0 to 30 ohm sender or do what Bill did.