Cleaning out rusty steel fuel tanks

[The Lorax]

This a great thread, I have learnt so much.
and Maico490 you have selections from the stone age right up to modern chemical and electrical means of cleaning rust! I am impressed.
I wondered why you had been so quiet Andy, now I see....

 

[scootr]

Shotgun pellets.

I have used #6 lead shot mixed with diesel. Shake the hell out of it. That evapo-rust looks like the way to go to me, much less labor.

 

[Lakeside53]

I wondered why you had been so quiet Andy, now I see....

Ha... yep...

I have three bridgeports in various stages of rebuild, a zillion other projects, doors to make for my barn before the rain, more wood to gather (cut, haul, split, stack), and now my truck failed emissions, has leaky injectors and my tabs run out in a week. Guess I'm going to be busy again. My problem is that I can't run down a goed deal... heck, I can fix that...

I was noticing last night that in a three car garage (one car only) full of projects, the only partially clear work space is a 3 feet x 16 inches on one bench... Of coiurse, there is a 450lb lathe on the bench now.. and no where to put it.

It's about this time I wish I had a couple of 18 year old kids to put on the chores..oh.. wait.. my neighbors have kids, and they are just as busy...:greenchainsaw:


I did get three saws done yesterday... The last muffler mod I did on a 361 I just gave the guy the muffler from my saw... that was a month ago...

 

[maico490]

Alchemy

This a great thread, I have learnt so much.
and Maico490 you have selections from the stone age right up to modern chemical and electrical means of cleaning rust! I am impressed.
I wondered why you had been so quiet Andy, now I see....

+1. Thanks everybody for the excellent replies I'll certainly be better prepared next time.
Bearing in mind the quantity and quality of the replies the next thread I start will be entitled :


"Turning base metals to gold"



I would appreciate replies to be sent by PM if that's OK.

 

[The Lorax]

Can't help with alchemy I am afraid.
But what I do know is that a Maico 490 running well can turn a strong man into a quivering pile of jelly in short order.
Of course thats assuming he can start the thing with that basted left hand kicker!

 

[Rookie1]

Nice job Lake. Nice pics too. I thought I was busy, but not at all compared to you.:yourock:

 

[maico490]

Can't help with alchemy I am afraid.
But what I do know is that a Maico 490 running well can turn a strong man into a quivering pile of jelly in short order.
Of course thats assuming he can start the thing with that basted left hand kicker!

Hi Lorax. I sold my 490 about 5 years ago and have regretted it ever since. I tried racing it against modern bikes but it couldn't handle the huge jumps they litter the tracks with these days. Oh and the front brake had about the same effect as putting your hand sideways in the wind.But that engine would whip everything other than a 500 Honda or Kawasaki 2-stroke but even against them the Maico generally gripped better out of the gate. One of the best things I've experienced in life is going from 3rd to 4th on the Maico on a long start straight and passing modern 450 4-strokes like they were 125s. After the race riders would come to look at the "piece of junk" they had sneered at earlier to see what was going on. All they got to see was a sand cast air-cooled engine without a single trick on it, not even a reed valve and couldn't work out how something so simple could make so much power.(Yes I do know about the KTM 495 but they had a hit in the powerband that turned grown men to jelly)
Starting it was no problem as long as it was jetted right and you used the decompressor but there was a knack. Once hot I could start it with my left foot from the seat no trouble.
My advice would be if you're not sure about parting with something cherished: DON'T

 

[mattinky]

Hi Lorax. I sold my 490 about 5 years ago and have regretted it ever since. I tried racing it against modern bikes but it couldn't handle the huge jumps they litter the tracks with these days. Oh and the front brake had about the same effect as putting your hand sideways in the wind.But that engine would whip everything other than a 500 Honda or Kawasaki 2-stroke but even against them the Maico generally gripped better out of the gate. One of the best things I've experienced in life is going from 3rd to 4th on the Maico on a long start straight and passing modern 450 4-strokes like they were 125s. After the race riders would come to look at the "piece of junk" they had sneered at earlier to see what was going on. All they got to see was a sand cast air-cooled engine without a single trick on it, not even a reed valve and couldn't work out how something so simple could make so much power.(Yes I do know about the KTM 495 but they had a hit in the powerband that turned grown men to jelly)
Starting it was no problem as long as it was jetted right and you used the decompressor but there was a knack. Once hot I could start it with my left foot from the seat no trouble.
My advice would be if you're not sure about parting with something cherished: DON'T

Man, those Maicos were great bikes, I sold off a bunch of vintage Huskys I restored and now I wish I had'nt... I know how you feel. Isn't it a shame that motocross has become nothing more than a jumping contest? I raced MX up until the late 80s when it started to get real crazy and decided to switch to hare scrambles after several injuries. I really like Hare Scrambles but I do miss racing MX on the old natural terrain tracks, to me thats real Motocross!

 

[buzz sawyer]

I had to clean my metal RMX250 (Japanese street legal) tank out.
I got a big handful of pea gravel and put some water in with it and shook it and rinsed it x6 then when the water was clear when I rinsed it out I just left it dry with a good slosh of WD 40 to displace the water.
I have never used that Kreem stuff, seen it advertised but as I am now running premix I don't have any problems with rust coming back.
I think the pea gravel cleans the best as it is slightly abrasive not just sharp.
Maybe try the screws then the pea gravel?

Ditto on the grqvel. Instead of water use mineral spirits or wd 40.

 

[CharlieG]

I used washing soda, cleaned out the Suzuki 2 strokes gas tank to new. Safe was important, and no hazmat chemicals after .

 

[The Lorax]

Yep the old air cooled two strokes were a blast to run, I grew up riding Yamaha IT's Suzuki PE's and the old KDX's, man were those fun days.
I still remember getting my first watercooled bike a 1991 CR250 and thinking whoa this is quick and quiet!

 

[oneoldbanjo]

I have just worked on several motorcycle tanks on vintage bikes. The old steel tanks were not treated with anything to prevent rust....and this new fuel will really rust an old tank quickly if you let it sit for any length of time with fuel in it.

I used to do the shake method with nuts and bolts and then drywall screws and it will get rid of loose scaly rust - but not the thin surface rust and it does not prevent the rust from returning.

My current method involves starting out with a product that will remove the rust by just soaking and won't hurt paint....like this product:

http://www.eastwoodco.com/shopping/...UCT&iMainCat=467&iSubCat=473&iProductID=11123

After the rust is removed and the tank is flushed out I use a wash with muratic acid to etch the metal, then a couple of rinses with water to get the acid out, then the tank is rinsed with Acetone as it will remove all traces of water and you rinse a few times with Acetone until it comes out clear. Before the Acetone has a chance to dry you add the tank coating material like Kreem or the Eastwood product to coat the fuel tank.

http://www.eastwoodco.com/jump.jsp?itemID=162&itemType=PRODUCT

I did not like the idea of turning my nice clean shiny metal tanks with a white coating of goo......but since the rust keeps coming back if you put new fuel in it.....even if the fuel is a 2-cycle mix.....I now coat every steel tank. If someone else wants the tank back to metal it only takes a flush with Acetone to remove the liner. I have never had a problem with the tank liner coming loose and I have used regular fuel and Avgas 100LL in my tanks.

 

[kevin j]

Q have never had a problem with the tank liner coming loose Q


I think the acetone wash is the key: I tried to reuse some acetone that was apparently saturated and not taking out any more water from the phospate acid step. The Kreme set up nicely, then a week later started coming out in big sheets, eventually like one big bladder liner pulled most of it out.
Ohterwise, when using fresh acetone and following directions properly I have had great experience with Kreme coating steel tanks usually mc tanks.

I use HVAC #8 x 1/2 long sheet metal self piercing screws in the acid bath step, and shake a long time. But for sure don't scrimp on the step #2, acetone flush.