Marbles Motors failed gas tank liner, then screwed up the warranty repair!

bosco659

XS650 Guru
Top Contributor
XS650.com Supporter
Messages
1,581
Reaction score
3,482
Points
263
Location
Oakville, Ontario
Hey; in my eternal quest for cheaper solutions, I suspect I may have tripped over the basis for the evaporust chemicals.
https://www.irohedp.com/two-uses-organic-phosphonic-acid-hedp/
I know crap about chemistry but this stuff sounds promising and tantalizingly similar to the touted uses of evaporust.
Anyone want to take the deep dive?
Trying to find some of this stuff in reasonable consumer quantities but it's typically sold in industrial scale, ie you want a 55 gallon barrel or a 235 gallon tote?
I’ll ask my chemistry friend.
 

DogBunny

Motorcychologist
Top Contributor
Messages
3,068
Reaction score
3,005
Points
263
Location
Austin, Texas
63672_I.jpg

https://www.harborfreight.com/520-lb-rust-cutting-resin-abrasive-tumbler-media-63672.html
I've posted this before...
Using this media, I tumble the tank in my clothes dryer. The media is pure resin, no abrasives, and is extremely hard. It's hell on rust, but does not harm good metal. It used to be a Harbor Freight-only thing, but is now sold lots of places.
Clothes dryers tumble too fast -- centrifugal force keeps the media in one place, it does not tumble through the tank, but it still moves enough to work. You just have to keep repositioning the tank every 5 minutes or so. It really works great on all of the outermost tank walls. Getting it to work on the tunnel is a bit of trick, but with some ingenuity you can get the media to clean it too.
You want to really stuff the dryer with pillows, cushions, sleeping bags, etc. I have a big dryer. Tanks may not fit in all consumer dryers.
I just did a tank about a month ago. It really does a great job. Couple things I learned on this latest job: Use petcock blank-offs, as has been said, but also make sure you have a tight gas cap, or make a blank-off for it too. Otherwise you will get red iron oxide (rust) all through the dryer -- that stuff is incredibly fine. And, if you do this to a tank with good paint, wrap it in several layers of stretch wrap, like is used to wrap palletized loads. I suppose Saran Wrap could be used -- use the whole package.
 

Jim

Beyond the edge is the unknown. Here be Dragons
Top Contributor
XS650.com Supporter
Messages
11,456
Reaction score
43,572
Points
813
Location
Kansas City Mo.
My “new to me” ‘79 has some very minor surface rust spots.
If it's just minor spots, I'd just let it be. My SG has a few spots in it. When I restored the bike I just let 'em be. That was about 3 yrs ago and they haven't progressed any.
Long as they stay the same, they're welcome to stay.... and as long as you keep water out of the tank, the gas will keep 'em from gettin' worse.
 

gggGary

Simplest truths meet the sternest resistance F D
Top Contributor
XS650.com Supporter
Messages
26,491
Reaction score
39,909
Points
813
Location
Baraboo, WI, USA
If it's just minor spots, I'd just let it be. My SG has a few spots in it. When I restored the bike I just let 'em be. That was about 3 yrs ago and they haven't progressed any.
Long as they stay the same, they're welcome to stay.... and as long as you keep water out of the tank, the gas will keep 'em from gettin' worse.
Agreed, I only work over badly rusted tanks. Been thinking about a tank rotisserie the power head from a garage door opener may be a great starting point.
 

DogBunny

Motorcychologist
Top Contributor
Messages
3,068
Reaction score
3,005
Points
263
Location
Austin, Texas
Agreed, I only work over badly rusted tanks. Been thinking about a tank rotisserie the power head from a garage door opener may be a great starting point.
I also agree, you can run tanks with a surprising amount of rust in them with no harm.
I saw a tank rotisserie on YouTube, or someplace, many years ago. Yes, that's the ticket.
 

DogBunny

Motorcychologist
Top Contributor
Messages
3,068
Reaction score
3,005
Points
263
Location
Austin, Texas
I have resurrected a couple of El Caminos that had been sitting for decades. Got them running using a fuel bottle, and directed the output from the fuel pump into a bucket. Run engine until no more ancient fuel comes out the fuel pump outlet hose. Add a couple of gallons of fresh gas to the tank, and repeat. Do this several times. Hook fuel pump back up to carb, fill tank all the way, and drive into the sunset. Can you imaging how rusty such a gas tank must be? The advantage here, is that you can't actually look into the tank and see how bad it is, so you don't freak out and do a lot of unnecessary rust removal. That's the disadvantage with a motorcycle tank, you can see into it, you see a little rust and freak out, and you unnecessarily de-rust it.
 

jetmechmarty

Project collector
Top Contributor
XS650.com Supporter
Messages
5,386
Reaction score
15,160
Points
688
Location
Coldwater, Mississippi
View attachment 206188
https://www.harborfreight.com/520-lb-rust-cutting-resin-abrasive-tumbler-media-63672.html
I've posted this before...
Using this media, I tumble the tank in my clothes dryer. The media is pure resin, no abrasives, and is extremely hard. It's hell on rust, but does not harm good metal. It used to be a Harbor Freight-only thing, but is now sold lots of places.
Clothes dryers tumble too fast -- centrifugal force keeps the media in one place, it does not tumble through the tank, but it still moves enough to work. You just have to keep repositioning the tank every 5 minutes or so. It really works great on all of the outermost tank walls. Getting it to work on the tunnel is a bit of trick, but with some ingenuity you can get the media to clean it too.
You want to really stuff the dryer with pillows, cushions, sleeping bags, etc. I have a big dryer. Tanks may not fit in all consumer dryers.
I just did a tank about a month ago. It really does a great job. Couple things I learned on this latest job: Use petcock blank-offs, as has been said, but also make sure you have a tight gas cap, or make a blank-off for it too. Otherwise you will get red iron oxide (rust) all through the dryer -- that stuff is incredibly fine. And, if you do this to a tank with good paint, wrap it in several layers of stretch wrap, like is used to wrap palletized loads. I suppose Saran Wrap could be used -- use the whole package.
:agree: This is the stuff I use as well.
 

Grimly

XS650 Addict
Top Contributor
Messages
439
Reaction score
1,382
Points
143
Location
Ireland
Trying to find some of this stuff in reasonable consumer quantities but it's typically sold in industrial scale, ie you want a 55 gallon barrel or a 235 gallon tote?

The annoying thing is, there will be some unadvertised use of it in an unexpected field, where you can buy smallish quantities for cheap.
In the meantime, I'll just stick with phosphoric acid and flush well afterwards.
 

Grimly

XS650 Addict
Top Contributor
Messages
439
Reaction score
1,382
Points
143
Location
Ireland
Clothes dryers tumble too fast -- centrifugal force keeps the media in one place, it does not tumble through the tank, but it still moves enough to work. You just have to keep repositioning the tank every 5 minutes or so. It really works great on all of the outermost tank walls. Getting it to work on the tunnel is a bit of trick, but with some ingenuity you can get the media to clean it too.
I've been thinking of using my cement mixer for the next rusty tank. Fairly slow running.
 

gggGary

Simplest truths meet the sternest resistance F D
Top Contributor
XS650.com Supporter
Messages
26,491
Reaction score
39,909
Points
813
Location
Baraboo, WI, USA
I've been thinking of using my cement mixer for the next rusty tank. Fairly slow running.
You been reading my mind! Spent time perusing cement mixers this afternoon Bonus some have plastic drums!
Saw one advertised as 27 RPM seems perfect.
 

Jim

Beyond the edge is the unknown. Here be Dragons
Top Contributor
XS650.com Supporter
Messages
11,456
Reaction score
43,572
Points
813
Location
Kansas City Mo.
This video poached from @MaxPete cafe build thread, gentlemen….the ultimate tank medium tumbler, it not only tumbles the tank, it rotates it so all sides are treated. Engineers rule the world. ;)
Yikes!! that was the tank that was possessed by demons. :yikes:
 
Top