View Full Version : Leaky tank problem

Video Man
12-07-2011, 03:40 PM
I volunteer at the local rail museum,where we have a General Motors E9 diesel passenger locomotive. It has two large engines, each of which has a coolant storage tank of welded, galvanized steel, about 3x3x3 feet. They have both developed pinhole corrosion in the bottoms and are leaking...the problem being, they are buried inside the engine compartment in such a way that they are not removable. Access is limited. There is a small inspection port in each. I'm scratching my head for a process of repairing these leaks. Any help would be appreciated!

I'm thinking: needs to be repaired from inside? Would some kind of mastic or chemical work? (I know a guy who repaired a motorcycle gas tank with some kind of epoxy made for the purpose, poured inside as a coating --- is there a similar fix here?)

12-07-2011, 03:53 PM
Clean it out and use a pourable silicone.

Weston Bye
12-07-2011, 03:56 PM
I'm certain that there must be better ways, but I once plugged oil leaks on an S-10 oil pan using JB Weld from the outside. The pan started leaking at the spot welds where an internal baffle was attached. I drove the truck home in the evening, drained the hot oil, cleaned the outside of the pan with sandpaper and then laquer thinner, then smeared on the JB Weld before any remaining oil could seep out. Lasted the rest of the life of the truck, several years of daily use.

As I said, there are probably better ways. How deep are the tanks? A head of water may exert more pressure on the repair than a few quarts of oil.

12-07-2011, 04:06 PM
Leaking water seals on bottoms of the tank rings, of the huge gas storage tank in downtown LA, were sealed in early 1962 using a material from the oil and gas drilling industry. Evidently still working. Don't ask how we placed it.

Look up Adomite, a clay like powder, which when wetted will settle to bottom and becomes quite hard, and impermeable.


12-07-2011, 04:18 PM
Agreed on the epoxy -(if that,s what it is,) used to patch leaky gas tanks, might be a problem getting it to spread around on a staitonary tank of that size, but it should work.
A bit pricy but it is used a lot on antique car tanks, i think it,s around $60.00 a quart up here.
The stuff i seen looks like thick aluminum paint.

12-07-2011, 04:37 PM
These folks make a product for that purpose. I've used it for three 6gal outboard motor fuel tanks. Worked well for me.


Though the por15 fuel tank repair process involves first cleaning it thoroughly with a product they provide, by shaking/sloshing; and application of the sealer also needs sloshing around inside. That's going to be a major problem in your situation.

12-07-2011, 04:51 PM
Just my opinion but I've found that regular JB Weld works a lot better than the 5 minute kind.

12-07-2011, 05:02 PM
Sodium Silicate (Waterglass) might be another option.

12-07-2011, 05:30 PM
About 15 or so years ago I had a similar problem with an air tank repair I did. I welded in a new piece with a wire welder using flux cored wire. I was new to welding at the time and got some porosity. The fix for me was to clean the inside of the tank with inhibited acid which I obtained from a local A/C supplier and clean the metal and any rust to bare clean virgin metal. This acid is one that will eat rust & corrosion but not good steel and is used to clean water cooled A/C units. After thoroughly drying I poured in a thin epoxy called Steelflex made by Fasco http://www.fascoepoxies.com/products.html and rolled the tank around until the interior was completely coated. Since that time the tank never has any rusty color in the condensate I drain out and there are no air leaks. The pressure is limited to 130 PSI so I cannot attest to how this might work at high pressures, but it doesn't sound like you're dealing with that anyway.

Another option might be to use a fuel tank repair kit similar to Kreem Permatex, POR, etc). There are other similar products made by other companies but I can attest that the Kreem product is quite good. The kit includes an acid that cleans the tank (probably like the inhibited acid previously mentioned) and a sealer that adheres to the clean inner surface.

I believe the Kreem or similar solution would be more expensive than my first suggestion.

Video Man
12-07-2011, 11:32 PM
Thank you, gentlemen, a lot of good information to start working on. Cleaning the internal corrosion in these tanks is a head-scratcher due to the limited access into the tanks and their size. I'll start persuing your leads, and thanks again!:)

12-08-2011, 12:09 AM
I had a leak in a 1" deep water pan for a air conditioner unit. Had to fix it quick... So I just wire brushed off as much of the corrosion as I could, And hit it with 10 coats of fast drying paint that was rated for underwater use (or somesuch!). Worked for years afterwards till I retired the AC unit.

Galvanized metal is not to be used as a water tank :(

Video Man
12-08-2011, 04:33 PM
This is a radiator coolant tank for a diesel locomotive, guess they made them that way in the 1950's. Part of the concern for a repair is there seems to be (although I can't find a spec) a huge flow through the tank. The input and output pipes are about 4 inches in diameter. I expect in a cubic yard of coolant there's a lot of turbulance, which makes a repair even more difficult.

I appareciate all the good thinking and ideas, gentlemen, I'll post a solution when we come up with one!:)

12-08-2011, 04:52 PM
Sodium Silicate (Waterglass) might be another option.

Hmmm... really? Sodium silicate is water soluble. I use it after a calcium chloride wash to harden and seal cardboard mortars. The cardboard is impregnated with calcium chloride and then the sodium silicate wash causes an ion replacement reaction so I'm left with calcium silicate, which is insoluble in water.

Videoman - That turbulence can severely aggrevate the corrosion issue. Any debris, rust flakes, etc will get hammered around and can accelerate the wear issue. I think maybe this is referred to as corrosion-errosion accelerated wear? So, yes, the flow rate is an important thing to consider. Many of the epoxy repairs were meant for low flow rate applications and/or low temperatures (like in a fuel tank). I'm interested to hear how you manage to repair these.

12-08-2011, 05:22 PM
Try a product called Belzona it is a industrial version of JB weld I have used it to repair some pretty worn parts on the ships I have been on.

12-08-2011, 06:12 PM
The inside of the tank must be quite dirty I assume that there is a drain plug hopefully large. My thought would be to insert a rotary water blasting head (Idon't think you can get one that can use a sand additive if you can that may be the way to go) in the inspection hole to get the most of it out.( the type they clean pipes with)Then fill the tank with baking soda and water (self tapping screws in the holes) and put a anode in push a current through it, you may have to do it a few times to clean it but I think it will do it. I used my single phase welder to put the charge through my drill press stand that was quite rusty made of second hand steel that was stored out side.It would have been in a tank about the same size as your tanks and I used about kilo of baking soda and about five hours of power on the lowest setting on the welder the only thing is, stay with in the duty cycle of the welder I got distracted and had to have a repair done. It cleans the steel back to gray when you water blast it clean put an inhibitor in the water to stop the rust bloom as the steel drys then your epoxy coatings or what ever you choose to use as sealant has good chance of sticking ---food for thought
Cheers Kiwi

12-08-2011, 06:22 PM
Part of the concern for a repair is there seems to be (although I can't find a spec) a huge flow through the tank. The input and output pipes are about 4 inches in diameter. I expect in a cubic yard of coolant there's a lot of turbulance, which makes a repair even more difficult.

If you should use the epoxy solution I doubt that turbulence will cause trouble as long as the tank is cleaned thoroughly before application so adhesion is assured. A large proportion of water tanks in fire apparatus are made of fiberglass these days. They are repaired when they crack due to flexing of the chassis with either fiberglass or epoxy resin.

12-08-2011, 06:57 PM
Kenworth block sealer.......

12-08-2011, 07:20 PM
Hmmm... really? Sodium silicate is water soluble. I use it after a calcium chloride wash to harden and seal cardboard mortars. The cardboard is impregnated with calcium chloride and then the sodium silicate wash causes an ion replacement reaction so I'm left with calcium silicate, which is insoluble in water.

Im not quite sure how the reaction works, but it is used to seal up leaky engine blocks among other things.

12-08-2011, 07:23 PM
Kenworth block sealer.......
Are you trying to say "K&W block seal"? Duhhhhhhhhhhhhhhhh
I don't think that this tank has the temperature to make it work, assuming that the prime movers run.For that amount of K&W he could build a new tank.

Videoman, where exactly is this tank located? Is it for expansion or reserve capacity? I assume but may be wrong that this is a pressurized cooling system. If so I,m curious about the pressure as a rectangular tank can't take much. Please advise.

Video Man
12-09-2011, 12:18 AM
@tdmidget, the tanks are located in the center of the engine compartment on the locomotive, between the two Diesel engines. They were probably installed on the chassis before the engine body was installed. They are now immovable, as there is no room except upwards to move them and the way is blocked by the upper structure of the locomotive body. There are also no doors big enough to pass them through, even if they were somehow gotten loose....as to pressure, and exact purpose, I am not sure. There must be some amount of pressure as the tanks are welded all round and have only small access panels which are sealed. And as I mentioned, the intake and output pipes are pretty big. I have just come onto this project, so I don't have any hands-on data from running the engine, but I'll try to find out more. Thank you for your and our fellow HSM's interest!

Rookie machinist
12-09-2011, 01:34 AM
Just a thought, could you weld a patch panel to the exterior of the tank? Won't solve the corrosion problem on the inside but could seal up the tank.

12-09-2011, 12:25 PM
Videoman that's the ones I thought they were. Some had a dynamic brake unit above them and some had a water tankabove them for the steam generator. If, hopefully, you don't have either of those obstacles then out the top is how you do it. I think there is a roof hatch there. I guess it's been empty for a while.

Video Man
12-09-2011, 04:43 PM
@tdmidget, thanks for the info. The tanks are encircled by all kinds of piping and obsticles, much of it rusted in place for 60 years....I'm pretty sure moving them is not going to be an option. I assumed that the dynamic braking system was up there as in a couple other passenger engines we have, not sure what it is but pretty sure whatever is there isn't going anyplace!:eek:

12-09-2011, 04:52 PM
Best bet might be to measure everything and build a new one in place. Might get lucky and find some stainless and then you won't have to fool with it every 60 years.

12-09-2011, 05:04 PM
You might just be able to plasma cut the bottom and install a new plate.

12-09-2011, 08:57 PM
Could you enlarge the inspection ports to gain better access?
If both are easily accessable then it would be relatively easy to use a plasma to cut them larger and then fabricate two matching cover plates.

Mr Fixit
12-09-2011, 11:51 PM
Video man, What about lining the tank with fiberglass? You will need a larger access hole to work on coating the sides and top. With a good cleaning and rust preventive first you should get a long life tank. Just another idea. P.S. Be sure and ware a approved for vapor respirator if you do fiberglass in a confined space.

Mr. Fixit :)

Video Man
12-10-2011, 06:39 PM
Lots of good ideas here, thanks, guys! I would post a picture if I could to show how limited the access is ---tanks are sitting in large brackets and there isn't room to swing your arm in the engine compartment. The small access panels make doing anything manual inside sort of like the surgery they do where they take out your liver through your navel...! We're going to pursue this with the hope of some kind of chemical cleaning and coating, I think. I'll post whatever we come up with! Better, I hope, than the last guy's effort, who put metal duct tape over the holes! Leaking into motors and generators mounted below, we got problems.....:eek:

12-10-2011, 06:52 PM
The guy who designed these tanks in place, must have later been an aoutmotive designer.:rolleyes:

12-10-2011, 07:16 PM
The guy who designed these tanks in place, must have later been an aoutmotive designer.:rolleyes:

Nahhhhhh, it lasted 60 years, they would have never given him a second thought.

12-12-2011, 06:46 AM
The place that did my spray in bed liner sprayed the water tanks of a lot of fire trucks. Not too large a port but larger than a handhole. The material was a 100% polyurea product and was hot applied. I can't remember the brand right now but 10 years of beating it hasn't phased it.

Video Man
12-12-2011, 02:02 PM
@BudB, I'd really like to pursue this lead if you have any more to go on, thanks!

Black Forest
12-12-2011, 02:10 PM
Yeah I can just see it. You driving your train down the street to the Rhino lining shop!!!

Joe Rogers
12-12-2011, 02:14 PM
Nah...they will come to you if the job pays enough. The Pentagon has used the product to harden the exterior walls (from the inside) to prevent terrorist attacks. I know they didn't deliver the Pentagon to the local spray company.:D

12-12-2011, 08:19 PM
Here's another vote for JB-Weld. I've used it on gasoline tanks and crankcase pans that have withstood the test of dozens of years and it is still golng strong.

Good luck!

Video Man
12-13-2011, 01:18 AM
The Rhino mention is a good lead, apparently they make a tank lining spray. Video here: http://www.youtube.com/watch?feature=player_embedded&v=ws0HDIfiQ4sideo

There's a dealer nearby who handles their truckbed product, will see if they can come and do this...and what kind of $$$ they need....:eek:

Black Forest
12-13-2011, 01:35 AM
We would use a lining called tnemec we sprayed on the inside of the frac trucks we built. It is a concrete lining used to line the acid tanks. It is a term much used in general as Zerox is used for copies. As in "Will you Zerox this for me?"

If you use Tnemec it will outlast the rest of the train!

Tnemec is cement spelled backwards!

Video Man
12-20-2011, 01:44 PM
<big sigh> Turns out these are not just coolant tanks, they are the intercooler for the oil system and are full of pipes, radiator fittings and other stuff to within centimenters of the sides of the tank....and even if not, according to the local Rhino dealer, too small to get their wands into for coverage, even if they were empty. Nothin' is ever easy. Thanks to all who have replied, your input is much appreciated!:)