TR2/3/3A Cleaning the gas tank...what have I done now?

[karls59tr]

I needed to repair the pipe connector on the gas tank as it was leaking so I pulled the tank. I decided to clean out the tank while it was out. I had done the muriatic acid followed by baking soda flush with success many years ago but I wanted to avoid working with the toxic acid this time around. I read about the variety of ways that a tank could be cleaned and decided on using phosphoric acid. When I went to the local Canadian Tire store I saw a container of Krud Kutter and I remembered that it was as one of the items you could use to clean out a gas tank(mostly used for preparing surfaces for paint) so I bought that instead of the phosphoric acid.
So I sloshed the container of Krud Kutter around in the tank and let it sit for awhile. The instructions said to rinse out after use "BUT" if the surface was unpainted you did not have to rinse because the chemical would dry and seal to the surface so that is what I did. I filled the tank with gas and the car ran great for a fast run on the highway. However the next time I went to start the car it wouldn't idle and kept stalling out. I checked the new fuel filter and it was half full of a black liquid and black flakes.....hopefully the filter got all the crap before it got to the carbs? I installed a new filter but am stll getting the hesitation,rough idle, and stalling.
There is only a couple gallons in the tank and I was thinking instead of pulling the tank(which I will do if I have to) I could possibly drain the gas out of the tank in the car and flush out the tank with??? maybe denatured alcohol? Any ideas?

 

[ed_h]

Karl--

Either the instructions were wrong, or you misinterpreted them. It's true that phosphoric acid will leave a coating of iron phosphate bonded to the surface of the steel that offers some protection against corrosion. However, you don't want to let excess unreacted phosphoric acid dry on the surface. It won't be bonded to the metal and probably isn't soluble in gasoline. It won't do anything good.

There can be several kinds of deposits inside a gas tank, and each has its own process for removal. Here is an approach that has worked well for me:

https://bullfire.net/TR6/TR6-63/TR6-63.html

Ed

 

[CJD]

Alcohol is also corrosive...not a good option for cleaning the steel tank.

 

[karls59tr]

Karl--

Either the instructions were wrong, or you misinterpreted them. It's true that phosphoric acid will leave a coating of iron phosphate bonded to the surface of the steel that offers some protection against corrosion. However, you don't want to let excess unreacted phosphoric acid dry on the surface. It won't be bonded to the metal and probably isn't soluble in gasoline. It won't do anything good.

There can be several kinds of deposits inside a gas tank, and each has its own process for removal. Here is an approach that has worked well for me:

https://bullfire.net/TR6/TR6-63/TR6-63.html

Ed

Thanks for the info Ed. I probably should have taken the time to follow the procedure you outlined. However the this product Krud Kutter was not phosphoric acid but rather a water based biodegradeable rust remover and inhibitor and on the instructions said: ..."to use as a rust inhibitor on unpainted metal,allow the inhibitor to dry on the surface after rust has dissolved. The remover will then protect bare metal against rust for up to 12 months." I probably should have gone the phosphoric acid route.
At any rate judging by the black liquid and black flakes in the fuel filter I believe that it might be a chemical reaction with the gas that is eating the lining of the fuel hose! unless there is some black material in the tank itself. I'm going to drain the tank,change the fuel hose from the tank to the filter and try fresh gas. Hopefully this solves the problem> In hindsight I think this Krud Kutter is basically to be used for exterior rust removal on metal to prep for painting not for interior use on gas tanks. Paying the price for a quick fix I guess.

 

[bobhustead]

Not to chide you, but to warn other less experienced folks, I repeat a frequent theme - "if it ain't broke, don 't fix or redesign it". There are no easy fixes from where you are. You need to drain and remove the tank. Then let it dry thoroughly (for numerous days). Take out the sender. Put a long flat screwdriver, or narrow pry bar, into the tank and scrape to see if you have goo or dry material on the tank bottom. If goo, send the tank to a rehabber unless you are a very good welder and can safely cut out and safely weld back a big panel on the top of the tank. If dry, gently hammer the tank bottom with the tank tilted radically toward the sender side to move the now dried crud to that side. Tape a piece of 1/2 inch PVC pipe to the inlet of a shop vac and put a small light into the fuel filler hole. (Tape it securely to a string in case you drop it.) Put the vacuum into the sender hole, look in thru that hole, and vacuum out the loose material. Do it again and again and again. Scrape all inside surfaces you can reach with screwdriver, prybar, etc.. Tap all surfaces of the tank with a hammer to dislodge more material and vacuum again. Do all steps again and again as needed until nothing rattles when you shake the tank. Put it back together and buy a few clear plastic fuel filters to change as needed (including on the side of the road) as flakes and pieces accumulate. I got my tank dry from long disuse and with lots of flakes and chunks inside. I am at 5000 miles and still have to change filters every 500 or so.

Bob

 

[charleyf]

If you have only had a few gallons of gas in the tank then what ever you have gotten out is from the bottom parts of the tank. If there is still stuff on the walls then --It is still in there!!
Is the stuff you used supposed to be used inside of an engine?? Would you purposefully plan to add it to your tank of gas?? I suspect not. Therefore I would say the best idea is to remove the tank and flush it out. The sediment bowls are meant to catch sediment not dissolved chemicals in the gas.
Charley

 

[ed_h]

Deposits in a fuel tank can be completely removed chemically. But since there is likely more than one kind of deposit, it normally can't be done in a single step.

Here are some before and after pics of a 43 year old TR tank.

Ed

 

[DavidApp]

My tank is clean bare metal inside.

Should I get one of the sealing kits that I have seen at one of the supply houses.
or
Take it to the local radiator shop and have them do the sealing.

David

 

[charleyf]

About 15 years ago I cleaned and then used a sealant on the inside of the TR3 tank. It appears to be the same stuff that is still sold by Moss for this purpose. Don't know if they have actually changed the product --BUT two years ago my son who now has the car replaced the tank because the coating was pealing off the inside of the tank. After that I have decided that if the tank is clean don't mess with it any more beyond that. We wondering if the ethanol might have been the problem. Don't know if it was or if they have changed the product.
Charley

 

[NutmegCT]

Question: are fuel tanks on today's new cars coated with something on the inside? Seems bare steel would be a risk.

Tom M.

 

[ed_h]

There is no reason tank sealers can't work, but they often don't. For them to work, the surface they bond to must be scrupulously clean and free of deposits or corrosion. That's the rub. Properly preparing a tank for sealer is an arduous process, and normally can't be done by just sloshing some liquid in it for a while.

Ed

 

[JohnB]

Haven't used the sealer but have cleaned out 2 old tractors and one TR2 tank over the
years.

Best cleaner for me was 1/2 pound of assorted size nuts and a foot of 1/4" link chain.
Dump inside and shake well, but gently. Took about 10 minutes as I recall. Remove all through
the sender opening, a strong magnet might help, and then vacuum out all the loose junk.
Rinse with some gas, close her back up and re-install.

 

[Geo Hahn]

...I have decided that if the tank is clean don't mess with it any more beyond that...

That works for me. Both my tanks are original and have never been cleaned, coated or even removed. I keep them fullish and on the one occasion when they were stored it was with a full tank.

 

[DavidApp]

Haven't used the sealer but have cleaned out 2 old tractors and one TR2 tank over the
years.

Best cleaner for me was 1/2 pound of assorted size nuts and a foot of 1/4" link chain.
Dump inside and shake well, but gently. Took about 10 minutes as I recall. Remove all through
the sender opening, a strong magnet might help, and then vacuum out all the loose junk.
Rinse with some gas, close her back up and re-install.

What happens to the parts of the tank beyond the baffle plates? The bolts etc can't get to that area.

As the tank has gone presumable gone for 45 years without coating and no problems I think I will probable leave it that way.
If it starts to leak at some time in the future I will invest in a new Aluminum one.

David

 

[JohnB]

The tractor tanks don't have baffles. And the Triumph tank has 2 so not that difficult to slide the bolts thru the cut out corners
of the baffle to "scrub out" each end of the tank. It sound tricky, but was not really that hard, just took time. A good rinse out
was important though.

 

[DavidApp]

My tank has spot welded baffles. Must have been oe of the changes made to the later cars.

David

 

[CJD]

That works for me. Both my tanks are original and have never been cleaned, coated or even removed. I keep them fullish and on the one occasion when they were stored it was with a full tank.

That is the key. Keep water out of the tank and use the car enough to cycle the fuel at least every year. You'll never have issues with internal corrosion. Our wonderful gasohol will gradually degrade to water, so burning a tank every year or less is very important. If you do go a full year on a tank, adding stabilizers to the gas would be prudent. Every vehicle I own gets run EVERY month. Even if it is just enough to warm it up and cycle all the switches. You cannot let a car sit for months or years without running into start -up issues.

Most of my experience with coatings is with motorcycles. Those tanks are easy to work with, but success was still hit or miss. I had so much trouble with pealing coatings that I personally would never coat a tank myself. If you had corrosion initially, you end up with a world of trouble when you have corrosion combined with pealing coating. I'd trash a tank before wasting my time trying to bring that back to life. It will save tons of frustration with fuel delivery issues later. Just not worth it!

 

[pdplot]

When I go south for the winter, fuel stabilizer goes into a full tank of gas and so far, in over 20 years, I've not had a fuel issue other than one stuck float - cured with a wooden-handled screwdriver. I would never put any type of harsh cleaner in the tank. Why look for trouble? It'll find you sooner or later.

 

[dklawson]

I have coated several tanks over the years so I will add my comments to those posted by others previously in this thread. I apologize that there will be some repetition.

I have used the white coating kits (Kreem), POR-15's Tank lining kit, and Red-Kote. As mentioned above, these coatings are special "paints" and just like regular paint, the quality of the results are 100% dependent on your preparation. Whatever kit you buy, follow its instructions to the letter with no shortcuts.

That said, I now offer comments on the kits.
Kreem:
Pretty standard prep steps (strong caustic, phosphoric acid, alcohol rinse, followed by an MEK thinned coating). The white coating is strong and resists ethanol. However, it turns amber after exposure to gas and if you are not careful with the prep work it can blister and peel.

POR-15:
Same basic prep steps as above but the coating solvent is much nicer to work with than MEK. The coating is metallic in appearance and does not stain after exposure to gas. If possible, apply two thin slosh coats. A single heavy coat can result in pinholes that then allow rust to develop between the coating and tank... allowing the coating to sluff off.

Red-Kote:
Same prep steps as above. This red coating is MEK based/thinned like Kreem. However, it is reported to tolerate imperfections in the prep work better than Kreem or POR. I used Red-Kote on the last tank I coated and found it to be the easiest to work with.

Caswell Epoxy:
It has lots of good reviews but I was afraid to try it. It is hard enough to remove traditional slosh coatings. I was afraid of making a mistake with the epoxy and not being able to clean it off to try again.

Pre-cleaning:
There is a pre-cleaning method that can be used before you start with the nuts, bolts, and caustic tumbling mentioned in previous posts. Boil the tank. Wash the inside of the tank thoroughly with a strong caustic cleaner. Then fill the tank 2/3 full with water while it is on a gas grill. Heat the tank to boiling and let it boil for a few hours. Obviously this will be an all-day event. Rinse the tank completely at the end of the day. No, the tank will not blow up. Once you wash it and fill it 2/3 with water the resulting steam prevents any possibility of fuel burning. The boiled tank will be very clean when you are done but I would still follow the remaining prep steps listed on your tank lining kit.

You can see this will be very time consuming and of course you have to buy the kit so it is not free. If you have a local shop that can clean and seal the tank for you, go that route. If there is no shop near you who does this you have to decide if you want to tackle this yourself as a project or whether buying a new/used tank is a better option.

Regardless of your choice, I would suggest you drop and clean your existing tank again to get all the crud out of the bottom of the tank. If you don't you will be watching and changing fuel filters for quite a long time. I would also put a disposable filter right before the carbs and go ahead and clean them out to make sure they have not been blocked by anything that has worked its way up from the tank.

 

[karls59tr]

Well I ended up up scraping the black crud from the tank bottom as ed-h recommended. I used the spade end of a pry bar thru the filler hole. I sloshed clean gas around in the tank several times until it drained clean. Took the tank to a car wash and flushed it out with hot rinse water and let it dry in the sun. Installed a new fuel filter and new fuel hose. Installed a new spare Carter fuel pump that I had. Fired the car up but it ran rough and wouldn't idle much to my chagrin. Pulled the lids off the float chambers and saw that the one for the front carb was dry! On further inspection I found that the Grose jet was gummed up with black crap from the Krud Kutter. Installed a new Grose jet and now the motor purrs like well fed cat.:eagerness: