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Author Topic: Fuel Tank Sending Units - Modern Upgrade...  (Read 5184 times)

August 21, 2012, 12:24:01 am

southernman

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Fuel Tank Sending Units - Modern Upgrade...
« on: August 21, 2012, 12:24:01 am »
Guys, I had started another thread under the IDI section (yes, still a novice), but then remember I had promised to come back and share my solution to the age old problem of finding a sending unit for our old grease burners...

Well, after doing some research, I determined that my tank's depth was ~9.5"; and the calibration requirements between sender and gauge were ~33-240 ohms. Based on this information, I located a Moeller reed type Marine sending unit, with 9" of vertical travel; stainless steel construction; and proper resistance. Here's the part details:



While this part was on order (Product Description: Moeller Reed Switch Marine Sending Unit Tank Depth 9" - Product # 035761-10), I took my tank to the local radiator shop to have it boiled out; re-sealed internally; and external coating.

Once I had the sending and tank back in the shop, I started by fabricating a round adapter plate, which would be sandwiched between the new sender (it's gasket) and the fuel tank. Please note that when you cut the hole in the center of the adapter plate, you will have to offset it (towards the drivers side on my truck) ~ 1/2" to prevent the float from bottoming on internal baffles. Once you've drilled the main hole, you will quickly see which direction you need to adjust it. So, here's what I came up with for the adapter plate:



I drilled and tapped 5 holes (8-32) to accept stainless set screws, which were used to mount the sending unit. The set screws are loctite'd in and flush with the bottom of the adapter plate - do not over install them as it will lift the adapter plate and you will have a leak. Here's what it should look like:



Once you have drilled and tapped for set screws at the sender, check the sender for fit. You then drill 5 thru-holes (1/4") for self tapping screws around the perimeter of the adapter plate to mount everything to the tank. When final fitting, it may be necessary to shift the aluminum plate around some just to be sure the float isn't bottoming on a baffle. When you've got it located, mark the holes, and remove the assy. Drill holes through the top of the tank, corresponding to the 1/4" holes in the adapter plate, and mount the sending unit's adapter plate to the tank. Be generous with the sealing compound. I did not use a gasket. Here's what you should end up with:



Now, you can install, for the last time, your Moeller Sending Unit and wire the unit in. I used ss nylon nuts to secure the sender, with loctite on the adapter end. I also checked operation of the unit before final wiring, and the gauge worked perfectly, with much quicker response time than the original unit. And here's the final installed unit. It fits nicely under the sheetmetal, is made of stainless steel; it's calibration is spot on with no "catch up" cycles from top mounted pivots; and I can buy a replacment at any local marine store.



Like I said earlier, this mod worked great on my truck, and it's 100 times more accurate than the original hardware. I hope you fellas find this helpful, and I apologize it this is a redundant read, as I think I posted, originally, in the wrong forum.

I'm also testing here to see if my pics are actually posting with the text. If not, I'll just post the pics and you can see it's a simple job.

S





'82 VW Caddy w/ 1.6 NA Diesel - completely stock.

Reply #1August 21, 2012, 02:11:30 pm

8v-of-fury

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #1 on: August 21, 2012, 02:11:30 pm »
Well, this is quality work! I will be putting a link to this thread in the FAQ section. :) Good work!

Reply #2August 22, 2012, 12:46:19 am

southernman

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #2 on: August 22, 2012, 12:46:19 am »
Well, this is quality work! I will be putting a link to this thread in the FAQ section. :) Good work!

Thanks 8V, I appreciate the feedback and feel free to post as you like. If you want to take the time to re-paste the images between the text, even better. Again, just glad to bring some solutions for members.

David
'82 VW Caddy w/ 1.6 NA Diesel - completely stock.

Reply #3March 30, 2013, 12:45:13 am

8v-of-fury

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #3 on: March 30, 2013, 12:45:13 am »

Reply #4March 30, 2013, 01:01:14 am

shorttimer

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #4 on: March 30, 2013, 01:01:14 am »
Much appreciated write up.

Reply #5March 30, 2013, 12:03:22 pm

wolf_walker

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #5 on: March 30, 2013, 12:03:22 pm »
Well done!

I used to live in Rocky Mount, hour or so east of you.  :)
Many things we do naturally become difficult only when we try to make them intellectual subjects. It is possible to know so much about a subject that you become ignorant.
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Reply #6April 02, 2013, 09:33:40 pm

audilvr

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Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #6 on: April 02, 2013, 09:33:40 pm »
i used a sender out of an old westy.

Reply #7April 11, 2013, 02:58:00 am

shwak23

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    1990 VW Golf TD. Engine Code CY
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Re: Re: Fuel Tank Sending Units - Modern Upgrade...
« Reply #7 on: April 11, 2013, 02:58:00 am »
Does anyone think this would work on a MK2 tank?

Sent from Outer Space!