What is in my fuel tank?

[In The Ten Ring]

My fuel tank was sandblasted inside and coated with "renew" which is a teflon-impregnated rubber substance. I covered up and sealed off all openings, installed it back into the truck, and stuffed a rag into the fuel filler neck, within days of that I hooked it back up to the fuel and vent lines. For the past year, it has had a gas cap on the filler neck.

Today I peered inside.....there is a coating of yellow powder inside the filler neck. On the ribs inside there, are two white spots.

I called the company that did the renewing, they are equally at a loss. The man did suggest removing the tank and bringing it to him and that I unhook my fuel line and run a hose to a gas can for starting the engine (my next truck goal).

What could this powder be? Pollen? Mold?

[Fatherflash]

Is it possible the "renew" had not finished off gassing and when you sealed the tank, it continued to off gas which resulted in the powdering condition within the tank?

Asking this as a question...something to think about.

Seen this happen with other (AMS-S-8802) tank sealing materials when used on aircraft.

[In The Ten Ring]

Originally Posted by Fatherflash

Is it possible the "renew" had not finished off gassing and when you sealed the tank, it continued to off gas which resulted in the powdering condition within the tank?

Asking this as a question...something to think about.

Seen this happen with other (AMS-S-8802) tank sealing materials when used on aircraft.

Oh gosh, you've seen that with aircraft? What is the remedy there?

[Fatherflash]

Originally Posted by In The Ten Ring

Oh gosh, you've seen that with aircraft? What is the remedy there?

On aircraft, if possible, strip the sealant and start over. If not possible, encapsulate the suspect sealant and do the job again.

If you are suspecting mold, this may mean the tank sealant was applied over either an improperly cleaned tank which left cleaning residue or the tank may not have been cleaned at all. I underline because this is assumption, I cannot see the application/mold for myself.

In either case, it is possible the new sealant application will continue what is basically off gassing, it will crack due to presence of solvent (gasoline) and then fail. It's up to you how to proceed.

[In The Ten Ring]

Originally Posted by Fatherflash

On aircraft, if possible, strip the sealant and start over. If not possible, encapsulate the suspect sealant and do the job again.

If you are suspecting mold, this may mean the tank sealant was applied over either an improperly cleaned tank which left cleaning residue or the tank may not have been cleaned at all. I underline because this is assumption, I cannot see the application/mold for myself.

In either case, it is possible the new sealant application will continue what is basically off gassing, it will crack due to presence of solvent (gasoline) and then fail. It's up to you how to proceed.

ugh! Doesn't sound great, if that is what it is. I may have to get a steerable, lighted probe camera (neat tool anyway) and have a look inside by next spring. The company that did the work guarantees that for life and wants to look at the tank anyway, but I'd have to remove the bench seat again to get to the tank.

should I remove the gas cap (maybe cover with a screen) and allow air to get inside?

[Fatherflash]

Originally Posted by In The Ten Ring

ugh! Doesn't sound great, if that is what it is. I may have to get a steerable, lighted probe camera (neat tool anyway) and have a look inside by next spring. The company that did the work guarantees that for life and wants to look at the tank anyway, but I'd have to remove the bench seat again to get to the tank.

should I remove the gas cap (maybe cover with a screen) and allow air to get inside?

Honestly, best thing you could do for yourself is remove the tank and take it to the folks that did the work so they can figure it out. Ask them what they think it is and what will be done to remedy the situation.

If they state the tank was cleaned properly prior to application, the only other thing it could be (that I can think of) is the applied rubber coating was close to expiration or had expired prior to application.

I would recommend you find out the name and manufacturer of the applied product, take some photos of your tank and give them a call. They have engineers that developed this stuff and they will have likely seen your problem in the past. That is what the company who applied the sealant should do. Nothing wrong with learning for yourself.

If you are trying to find a solid camera probe, recommend here:
https://electronics.woot.com/offers/...ef=w_cnt_bs_13

Not the best, not the worst but it does get the job done.

Let me know if I can do anything else to help.

Bren

[71cheyennesuperlongb]

If I were you I would make sure the company that did it will stand behind it. They might try the old Its been too long now to warrenty it. If you brought it in 6 months ago we could have did something about it then.I would remove it and send it back NOW!

[In The Ten Ring]

Originally Posted by 71cheyennesuperlongb

If I were you I would make sure the company that did it will stand behind it. They might try the old Its been too long now to warrenty it. If you brought it in 6 months ago we could have did something about it then.I would remove it and send it back NOW!

No time for that now, not this close to winter. I spoke to the company owner by phone this week, I think he'll stand by his word. It has a lifetime warranty, it was done some three years ago aleady.

[special-K]

Aw heck, why wouldn't you go ahead and take a nice afternoon and pull the seat and tank? You could have all this corrected over winter while you are busy with the ski season. Good to go come spring, no hold-ups.

[In The Ten Ring]

Originally Posted by special-K

Aw heck, why wouldn't you go ahead and take a nice afternoon and pull the seat and tank? You could have all this corrected over winter while you are busy with the ski season. Good to go come spring, no hold-ups.

You are making a couple of assumptions that are incorrect.

1). Lots of stuff to move in the garage to make room for the bench seat to come out.
2). No help to count on and for me, that seat is a two man job.
3). Other things to do.
4). Lack of storage space for seat and tank....there is just no room in the garage for it and I am not putting the seat in the house.
5). Rain forecast this week and everything in the way of the bench seat has to be piled up outside.

See, the tank will have to wait.

[mike16]

Never seen anything like renew in the aviation industry. They dont mess around in that industry for obvious reasons. If its not FAA- PMA dont buy into that hype.