Welding on a factory saddle tank.

[uao85]

Hey guys I have been brewing up some ideas for my biodiesel/vegi-oil conversion and think I have an idea of what it will take. First of all I will be running dual tanks on an m1008, dual electric fuel pumps, valve selector, no mech pump, and all polyurethane reinforced lines from tanks to intake, and already have all the parts to do so. Well my question is in regard to the pass side tank that I will be using for the vegi oil to run off of after its warmed up. I got to thinking today, well the heater core I have is narrower than the fuel tank, and have eliminated the heater under the dash so I will already have a few ports open in the radiator that will be usable. Why not just put the heater core inside the fuel tank on the front of it by the fuel pickup with the ports sticking out so I can run the heating lines to them to have a built in heater for my veg oil tan, with the tank and lines where they stick out of the tank being sealed and all. What do you guys think, I know it will work, but wanted to ask about the whole welding on a fuel tank. BTW the tank is from a diesel truck, is completely empty, and has already been drained and all the fuel washed out. Any problems to foresee or things I should look out for?

 

[bajaviking]

How was the tank washed out? I believe there is a special solvent to use for this purpose, please ask somebody that really knows about this before you start welding, it can be very dangerous if you don't prep the tank correctly.

 

[Roland_Jenkins]

This is what I did and it didn't explode. Make sure all the fuel is out of it *duh*
I took out the fuel sending unit and anything else so it would ventilate and let it set for a few days with a air hose running inside of it.

When I finally did weld I ran the hose from an argon gas tank in it while I was welding. Argon won't feed the fire.

I also brazed a gas tank that had a crack up near the top. I rinsed the tank out several times with water and then filled it so the water was just below where I was going to braze.

It all went well both times but I got to tell you, had a popcorn kernel popped nearby I would have messed my pants.

 

[peterpan]

i don't recomend welding on a fuel tank
now with that said i have welded motorcycle tanks by filling them with water and leaving the cap off incase it did ignite any fumes it would just vent out the cap instead of blowing up but a truck tank is much bigger the water in the tank might reduce the fumes to a point that makes it allmost safe but once again i don't recomend welding on fuel tanks a guy at the local scrap yard here was killed buy a trying to cut a gas tank out of a car with a torch so if you weld on a tank its at your own risk they do make a wash that will make it safe but i don't know what its called

 

[k204dr]

I just cut a hole in my suburban tank, and made a plate to connect my steel line/heating coil to, and then silicone and screwed the plate down with self-tapping screws. just made a 2100 mile trip with no problems running straight wvo.

 

[uao85]

I just cut a hole in my suburban tank, and made a plate to connect my steel line/heating coil to, and then silicone and screwed the plate down with self-tapping screws. just made a 2100 mile trip with no problems running straight wvo.

Cut and patch eh????? Thats a new one to me............maybe its worth a shot. It would be available as a hatch in case any foreign particles get into the tank, or I need to change out the heater core element.........JBWELD TO THE RESCUE!!!!!!!!































jk I will have to check around on this one.
Thanks for the comments and keep em coming.


Regards,
Remington

 

[k204dr]

thats how alot of people converting tanks for wvo do it. works pretty good.

 

[Pookster]

why not just take an old tranny cooler, mount it to the outside of the tank on the bottom where the fuel pickup is. Clean up area, mount cooler and lines, use insta foam around edges, let it set. Then fill tranny cooler up with sand (better heat conductor, or if you have heat sink gel, but I think that might freeze, then put a sheet of thick aluminum if you have it) then use some more insta foam to cover it up. Sand down when dry, and paint with a high void epoxy paint.

I like this way better, there's no chance of coolant contaminating the oil, which results in the quick demise of your engine.

 

[uao85]

why not just take an old tranny cooler, mount it to the outside of the tank on the bottom where the fuel pickup is. Clean up area, mount cooler and lines, use insta foam around edges, let it set. Then fill tranny cooler up with sand (better heat conductor, or if you have heat sink gel, but I think that might freeze, then put a sheet of thick aluminum if you have it) then use some more insta foam to cover it up. Sand down when dry, and paint with a high void epoxy paint.

I like this way better, there's no chance of coolant contaminating the oil, which results in the quick demise of your engine.

You mean, pack sand all around the cooler in between the fins and all and around it, but after a while, wouldnt the sand just starting heating the tranny fluid since there is no airflow to the cooler, and its packed with something that soaks up alot of heat?? hmm well thats an idea, but I still wouldnt like the idea of something hanging below the tank to get scraped off somewhere down the road, plus I will have a skid plate running the entire length of the tank on both sides with no usable clearence in between. What about running the tranny cooler inside the tank as a heating element? If there is a leak, then the engine will still run off of tranny fluid, I guess I would have to keep tabs on the tranny fluid level pretty often......Hmm I am liking this idea a bit better since the ports to the tranny cooler are already on the pass side right next to where the tank will be................hmm yes yes I am liking this idea better and better................ Well what do you guys think about this??..............................BTW thanks for all the replys so far, its helping me brainstorm from every angle, critiquing(sp?) an idea never hurts.

Regards,
Remington

 

[diesel4me]

one problem??..

Only thing I see "wrong" with both ideas,is NO heat is produced until the engine is warmed up..

I assume your running a valve that you can shut off the veggie oil with,and run it out of veggie oil before shutdown..then start it up cold on diesel,and switch back to veggie oil..

(something I'd consider a pain in the butt--thats one reason MY 6.2 isn't using it--other than the lack of available veggie oil..here its considered "hazardous waste",and you cant legally take it from resturaunts unless your a licenced contractor ,and they must keep a "log" on how many gallons were disposed off,and who took it!)..

Wouldn't an electric heater be a better solution?...then you could just switch it on,and get instant heat to the veggie oil tank...but finding one that uses 12 volts could prove to be difficult..

I've seen VW Rabbits running waste veggie oil here--they use exhaust heat they rob from the muffler or exhaust pipe to warm up the oil..one guy simply wound copper tubing around the exhaust pipe just before the muffler!..I'd be afraid of it boiling and possibly exploding,but he says "naa--it'll never get THAT hot!"..another one I saw had a tank type block heater running off a 110V inverter as the waste oil "heater"..both looked scary to me!..

I thought about using an ordinary radiator from a small car with a built in tranny cooler,and running coolant thru the radiator,and the veggie oil thru the tranny cooler..it would help cool the engine AND heat the oil up at the same time!..but it'll still be ice cold the next morning!..

I'm interested in hearing more about using waste veggie oil..most of the guys using it here are giving up on it,as cold weather approaches..like me,they have found it difficult to get free,without a hassle..and if they forget to switch back to diesel before shutting them down,it can be a hassle to get them to start again!..

I'm wishing I could run a diesel on used crankcase oil..my friend nearly always has 100+ gallons at his repair shop,that is a pain to dispose of!.I'd have a full tank forever!...