Fuel Tank Issue

[rcl700]

I see that the fuel tank in the 48' has a"self cleaning" pickup tube/ filter. I'm in the process of rebuilding the fuel pump now but after blowing compressed air through the tank outlet I'm thinking the pickup is clogged. Air is not Flowing freely from outside in. 

Is this pickup flow both ways. I don't think there would be a check valve but worth asking.

 

If replacement  of tank is needed, I found this.. any thoughts on this tank. I have a Summit local to me. 

https://www.summitracing.com/parts/tnk-48dp-a/make/plymouth/model/p15-special-deluxe/year/1947

 

 

[Los_Control]

Probably your best bet ..... I bought a Tanks for my truck....I'm ok with it & like it .... Evidently summit has a contract with them & sell a bit cheaper.

I went through Tanks website for purchase, also got a sending unit .... I called in my order over the phone, the lady on the other end was very helpful & polite.

Just saying I would do it over again if needed.

https://www.tanksinc.com/index.cfm/page/ptype=product/product_id=226/category_id=68/mode=prod/prd226.htm

 

You can tell by looking at the area around the filler neck, that tank may be leaking already, or soon will be .... Hard to say whats inside it.

When I first got my truck running I used the original tank.  It would run fine, then some crap floating around in the tank got sucked up into the pickup tube & it would die.

The top of the tank was full of pinholes ..... Just thinking, the sooner you ditch that old tank & get a clean fuel supply the happier you will be.

[9 foot box]

   I would replace the tank with one that resembles the the original. I replaced mine with one from Auto City Classics. Sam got one from Vans Auto. Acetone might loosen the varnish in the filter element and the tank. If you can get low pressure air to blow through the filter, dump the acetone and use dishwasher soap and water with a length of 1/4” chain to scrub the inside. There is a special ferrule when you disconnected the fuel line from the tank. Don’t lose it. The tank I cleaned was for a truck, and didn’t have the filter, but I removed the sending unit and capped it and the inlet, for my process.  Rick D.

[Sam Buchanan]

13 hours ago, rcl700 said:

I see that the fuel tank in the 48' has a"self cleaning" pickup tube/ filter. I'm in the process of rebuilding the fuel pump now but after blowing compressed air through the tank outlet I'm thinking the pickup is clogged. Air is not Flowing freely from outside in. 

Is this pickup flow both ways. I don't think there would be a check valve but worth asking.

 

If replacement  of tank is needed, I found this.. any thoughts on this tank. I have a Summit local to me. 

https://www.summitracing.com/parts/tnk-48dp-a/make/plymouth/model/p15-special-deluxe/year/1947

 

 

 

Here is the tank I put in my '48 Plymouth, it is a near perfect replacement but doesn't have the trouble-prone pickup filter:

 

https://vansauto.com/product/41-48-dodge-plymouth-desoto-chrysler-6-cylinder-gas-tank/

 

 

A suggestion....if you replace the tank, replace the entire fuel system....lines, filter, hoses and pump. This is an area where if one component has gone bad the rest of the system is suspect. Just rip it all out, start over, and not have to deal with a car stranded due to faulty fuel delivery.  No need to ask me how I figured this out.......   

Edited May 21, 2023 by Sam Buchanan

[Kilgore47]

21 minutes ago, Sam Buchanan said:

Here is the tank I put in my '48 Plymouth, it is a near perfect replacement but doesn't have the trouble-prone pickup filter:

 

https://vansauto.com/product/41-48-dodge-plymouth-desoto-chrysler-6-cylinder-gas-tank/

I just ordered one of these tanks for the P15.  Last time I was under the car I noticed small leaks on the bottom of the tank.  I'll replace the fuel line at the same time.

[Tired iron]

if the tank is in good shape, and its just the pick-up filter screen that is plugged, you can unsolder the pick-up tube where it connects to the tank and then pull it out. then clean it, or remove/destroy the screen, and then solder it back in.  And, absolutely, no flame for the soldering...just one of the big old soldering copper irons that you heat remotely.

 

I'm not wanting to start a long thread about gas tank explosions...just offering up a trick to use IF the tank is worth saving.

[DonaldSmith]

Per 9 foot box, 

“The filter is located about 5/8 inch above the bottom of the tank; therefore, approximately three pints of water and sediment can collect below the filter.  It is advisable to remove water and sediment which may collect in the bottom of the fuel tank, about once a year.  Remove the drain plug when the fuel supply is low to drain off the accumulated sediment and water.”

 

There was a little more than an inch of gas in the bottom of the tank. I drained off almost 2 gallons.   Good news, no water on the bottom, no objects in suspension.  Troubling news, particles in the bottom of the drain pan (shown upside down here for dramatic effect.) 

 

 

 

For keeping the tank:  Ma Mopar designed the tank to filter the gas being sucked out, and to have the sediments settle, to be drained off periodically.  And the sintered bronze filter is supposed to be cleaned off by the sloshing of the gas in the tank,   The gas I drained off had the sediment settling quickly.  

 

For cleaning and sealing the tank, or replacing it:  Scary.  There is sediment for sure.  Looking into the tank shows the bottom  covered by grains of something.  

Last Fall the engine quit twice at highway speed, but re-started immediately.  One can imagine silt sucked against the filter and falling away when the engine stopped. 

 

Chime in, guys, while I mull this.  

[DonaldSmith]

See "Best Fuel Tank Restoration Method."  It seems we have roughly parallel threads. I checked out that thread, with its recommendations for the RenU process.  They hold the patents for recoating and sealing fuel tanks.  Although the patents ran out years ago, I'm impressed.  I'm dropping the tank and taking it to the local RenU licensee.  End of story.  I'll post any news on the other thread.  

 

 

[Rodney_Hamon]

I have a ‘36 dodge truck with the original gas tank. Way back in 1975 I relocated the tank from underneath the cab to the front of the bed and put it in a fake tool box. Reason was an R-10 overdrive was added to a newer engine and the tank didn’t fit due to linkage etc.  In 2015 or so after many years of the truck not running since 1986 or so I decided to take the tank to the last radiator shop here in Albuquerque to have it cleaned out. I wanted to reinstall the tank back close to where it should be. The varnish smells were pretty bad btw.  The old guy told me he would seal it his way as he thought new ones didn’t know what they were doing with all this new **** on the market.  I had been reading this forum and others about sealing tanks and was on the fence about it. Was considering not doing it. He convinced

me to. I did and took it home and let it sit in a garage for several months with the gas cap on. I should have let it breathe/air/cure  with open air I think.  When I installed finally and started the engine up I got green gas afterwards and had to drain the tank and clean the carb bowl and...was a pain. Did it twice. Engine ran shitty.   It settled down but I was spooked and could not bring myself to put more than a couple gallons or more of clean gas in to just start the engine.  I don’t know to this day if the tank lining is cured now or if I fill it..it will dissolve this lining.  Alas.  I wish I had never said yes to a recoat.  Well, it was all about saving $500 in a new gas tank being fabricated.  1936 is an odd year for gas tanks.  Bottom line...I monitor my fuel filter and replace it when it turns funny color.  

[Sam Buchanan]

Most of us are old enough to remember the Fram (?) commercial where the grizzled old mechanic says "You can pay me now or you can pay me later...". Very true, and a rule I learned the hard way. I now find it easier to just pay up front and be done with it. 

Edited May 24, 2023 by Sam Buchanan

[Plymouthy Adams]

today that commercial is You can pay me now and you can pay me again later as I did not diagnose the problem correctly the first time, nor the second and subsequent attempts these days. 

[rcl700]

LOOK AT THIS! ?

Well since I had the tank out I have been experimenting with it. I just washed it out and all I can say is wow. I have been using electrolysis rust removal method on it for a week. After rinsing it out today this is what I found. 

12v @10 Amp 

 

Now I'm thinking this tank can be saved. ?

Sorry for the poor quality photos is hard to get the phone to focus looking down the sending unit hole. 

Edited May 27, 2023 by rcl700

[rcl700]

[FarmerJon]

Wow! Looks great!

[rcl700]

[rcl700]

Does anyone know what type of gasket goes on the fuel drain plug? What was left of the old one looked like a paper type gasket. Should this have a brass compression washer? 

The underside of the plug I'd cupped. 

[DonaldSmith]

Hot topic for me.  My tank is being renewed.  I had taken the old plug out, and was reminded what I had done, lo those may years ago.  

 

I had cobbled a drain plug with a close nipple and a cap, 1/2" pipe size, with a rubber gasket compressed by the shoulder of the cap.  It worked for years. 

 

Thanks for the photo. That's what the plug is supposed to be.   The answer, a rubber gasket will work fine.

 

Mother Mopar built the tank with drain holes at the base of the threaded sleeve over the drain hole, so that every last drop of sediment and crud would be drained out, (every year as recommended?).  So a pipe plug would not work.  

 

I told the tank guy what I had cobbled for the drain, but he said he would get me something proper.  It'll probably look like plug in the photo above.  

 

 

[rcl700]

1 hour ago, DonaldSmith said:

Hot topic for me.  My tank is being renewed.  I had taken the old plug out, and was reminded what I had done, lo those may years ago.  

 

I had cobbled a drain plug with a close nipple and a cap, 1/2" pipe size, with a rubber gasket compressed by the shoulder of the cap.  It worked for years. 

 

Thanks for the photo. That's what the plug is supposed to be.   The answer, a rubber gasket will work fine.

 

Mother Mopar built the tank with drain holes at the base of the threaded sleeve over the drain hole, so that every last drop of sediment and crud would be drained out, (every year as recommended?).  So a pipe plug would not work.  

 

I told the tank guy what I had cobbled for the drain, but he said he would get me something proper.  It'll probably look like plug in the photo above.  

 

 

A few additional photos. Hope this helps.

[Sam Buchanan]

Rubber would definitely not be my first choice but if you use rubber be sure it is Viton, otherwise ethanol fuel will make short work of the gasket. I would use a copper crush washer similar to what is used on the oil pan drain plug.

Edited May 29, 2023 by Sam Buchanan

[rcl700]

29 minutes ago, Sam Buchanan said:

Rubber would definitely not be my first choice but if you use rubber be sure it is Viton, otherwise ethanol fuel will make short work of the gasket. I would use a copper crush washer similar to what is used on the oil pan drain plug.

Well, I'll need to locate one big enough. I think the outer rim is the only part that will touch the tank. So the washer will need to be larger than the head of the plug

[Sniper]

6 minutes ago, rcl700 said:

So the washer will need to be larger than the head of the plug

 More like thicker than the cup.

Hardware store should have a selection if your local parts store doesn't.  All else fails McMaster Carr has them.

 

Another thought is an O ring.  Buna N is recommended for gasoline, but doesn't handle ethanol well.

 

Fluorosilicone O rings can handle both and is recommended for both.  Again, McMaster Carr has them.

[rcl700]

On 5/29/2023 at 4:25 PM, Sniper said:

 More like thicker than the cup.

Hardware store should have a selection if your local parts store doesn't.  All else fails McMaster Carr has them.

 

Another thought is an O ring.  Buna N is recommended for gasoline, but doesn't handle ethanol well.

 

Fluorosilicone O rings can handle both and is recommended for both.  Again, McMaster Carr has them.

Any idea if nylon washer would work for the fuel tank drain? 

[Sniper]

I looked up the compatibility of nylon with gasoline and ethyl alcohol

 

Alcohols: Ethyl         A1-Excellent
Gasoline, unleaded     A2-Excellent

1. Satisfactory to 72°F (22°C)
2. Satisfactory to 120°F (48°C)

 

Not too worried about temp listings, my oil pan gasket is nylon, holds up fine and is listed as

 

Petroleum     A1-Excellent

 

I'd do it.

[rcl700]

40 minutes ago, Sniper said:

I looked up the compatibility of nylon with gasoline and ethyl alcohol

 

Alcohols: Ethyl         A1-Excellent
Gasoline, unleaded     A2-Excellent

1. Satisfactory to 72°F (22°C)
2. Satisfactory to 120°F (48°C)

 

Not too worried about temp listings, my oil pan gasket is nylon, holds up fine and is listed as

 

Petroleum     A1-Excellent

 

I'd do it.

Nice. Thanks for the quick informative reply.  I'll look for one that fit.