Best way to clean out gas tank?

[YoungWayne]

Tank has a bit of old gas, so I would like to clean it out a bit. Best method for cleaning the tank and draining it? I tried to remove the petcock but the screws holding it in place are in there pretty tight. I would like to clean out the tank and maybe put some of that protective stuff that you can put in there to help the tank. 

[Pasta Burner]

I’ve just used water in the past following an ethanol attack.  

[YoungWayne]

5 hours ago, Pasta Burner said:

I’ve just used water in the past following an ethanol attack.  

You fill up the tank with water to clean it? To clarify, I'm asking how I would empty the tank once it is filled with gas or cleaning solution

[Pasta Burner]

25 minutes ago, YoungWayne said:

You fill up the tank with water to clean it? To clarify, I'm asking how I would empty the tank once it is filled with gas or cleaning solution

Oooff sorry.  I assumed you had the tank removed.  I haven’t done it on my venture, haven’t had the need, but on my sport bike I ended up siphoning out all the gas I could, scooping out all the crud with paper towels and if memory serves correct I flushed it with water and paper towels or a sponge then flushed with water and shop vac it out once I had a good feeling the vapors weren’t going to be a problem.  I don’t remember removing that tank but I could have.  Regardless I did have all fuel and return lines disconnected as to not induce water into the system.  Dried with towels and let it air dry before putting it back together.

Just picturing in my mind the venture tank and small filler neck. I think removing it and doing a rinse would be best, to drain it maybe put a pan under the petcock area and loosen the screws and let it go.  My petcock gasket failed this spring and that’s exactly what I ended up doing after I siphoned out as much as I could.  It was messy but it is what it is sometimes.

 

Edited October 20, 2021 by Pasta Burner

[YoungWayne]

57 minutes ago, Pasta Burner said:

Oooff sorry.  I assumed you had the tank removed.  I haven’t done it on my venture, haven’t had the need, but on my sport bike I ended up siphoning out all the gas I could, scooping out all the crud with paper towels and if memory serves correct I flushed it with water and paper towels or a sponge then flushed with water and shop vac it out once I had a good feeling the vapors weren’t going to be a problem.  I don’t remember removing that tank but I could have.  Regardless I did have all fuel and return lines disconnected as to not induce water into the system.  Dried with towels and let it air dry before putting it back together.

Just picturing in my mind the venture tank and small filler neck. I think removing it and doing a rinse would be best, to drain it maybe put a pan under the petcock area and loosen the screws and let it go.  My petcock gasket failed this spring and that’s exactly what I ended up doing after I siphoned out as much as I could.  It was messy but it is what it is sometimes.

 

I think it's best if I leave the tank on, from what I understand I will basically need to remove a part of the frame or something like that. 

SO... I tried unscrewing those petcock screws, even with an impact driver they're not coming loose. I might have to drill a hole and pull the screws out like I've had to do with a couple other screws.

But it sounds like once they're loose the gas will flow through? I will have to try to get those screws out of there. Any recommendations on what I should put in the tank to help clean it? Once it's empty I plan on putting fresh gas in it and maybe something to clean the tank and fuel lines but I'm not too sure what that something would be.

[Pasta Burner]

Now thinking back those screws were a bitch.  I had to remove the right side exhaust.  I may have even used vise grips and replaced them with new screws.  It was one of those oh shit projects when I went to work in the morning and discovered a bike leaking gas in the garage.  Took some time off that day to come home and fix it, so I don’t remember exactly all what I did.   I did however by chance acquire the bike with an oem petcock gasket in the saddlebag.
 

I was going to suggest after getting the petcock out just flushing with a hose but I’d like someone else to chime in if that would harm them pump or float.  I wouldn’t think so but for sure don’t want to give you bad advice.

Edited October 20, 2021 by Pasta Burner
Added more info

[Patmac6075]

It’s been a long time since I was down there, but why couldn’t you just pull the fuel line before the fuel pump and let gravity do its job? While you’re down there you should also replace your filter.

You may not get 100% of the old fuel out, but you’ll get a good portion….once you’re up and running and have run through a few tankfuls you’ll have gotten rid of most of the old varnish and gels (especially if you run some SeaFoam through with every fill up). Keep an eye on you fuel filter and maybe proactively change it out after 10-15 tankfuls.

After that…keep your tank topped up and use non-ethanol 100% gasoline…you should be fine.

 

[Patmac6075]

Just reread your original post….I wouldn’t try to put in a tank sealant in unless I was positive it was rusted through and only as a last resort. You’ll need to pull the tank in order slosh the cleaner/etch and the sealant around the tank.

Again, in my opinion, draining as much as you can and refilling with fresh clean gas plus repeated fill ups should clean out any old funky gas (plus the added benefit of extra ride time). And a clean new filter should take care of most of the particulate matter.

Sorry for the double post

[YoungWayne]

4 hours ago, Patmac6075 said:

Just reread your original post….I wouldn’t try to put in a tank sealant in unless I was positive it was rusted through and only as a last resort. You’ll need to pull the tank in order slosh the cleaner/etch and the sealant around the tank.

Again, in my opinion, draining as much as you can and refilling with fresh clean gas plus repeated fill ups should clean out any old funky gas (plus the added benefit of extra ride time). And a clean new filter should take care of most of the particulate matter.

Sorry for the double post

Thank you very much I will try to do what you suggested. I will try to find where the fuel line is and maybe post a picture to make sure I got the right one. 

And You're saying I can put some seafoam in there when I put in some gasoline? I will try that.

[Pasta Burner]

1 hour ago, YoungWayne said:

Thank you very much I will try to do what you suggested. I will try to find where the fuel line is and maybe post a picture to make sure I got the right one. 

And You're saying I can put some seafoam in there when I put in some gasoline? I will try that.

Yep!  Seafoam is liquid magic! 

[Patmac6075]

Ha ha….I prefer SeaFoam….ask 10 other members and you’re likely to get 10 different opinions, kind of like if you ask which oil is the best or which tires are the best.

The reality is, you tend to stick with what has worked for you in the past. In a past life I was a regional commercial sales manager for a national auto parts chain. I had the opportunity to work with the national sales manager for SeaFoam…great guy…he got me hooked on all their products, interesting side bar…SeaFoam, Deep Creep, and their Trans fix are all pretty much the same active ingredient in different concentrations. I also love their other product Bug-b-Gone for removing bug spatter from my bike (although it’s a completely different product than SeaFoam).

[YoungWayne]

Is my tank shot? To my untrained eye it seems to be pretty rusted. I haven't drained the tank yet, but it was barely has any gas in it. Is this fixable and would I have to take the tank off? I might just buy another tank if I'm going to be taking it off, but I would prefer to save some $$$ and clean it if possible.

[Marcarl]

I will be very interested in the opinion of others, I'm not very savvy when it come to rusty tanks and what to look for,,, but,,,, Yah you knew that was coming,,,, but,,,, looking at what I can see my thoughts are, there is rust there that is just waiting to plug a fuel filter, and if what I see is only a sampling then there is a great possibility that there could be just one little spot somewhere that is almost rusted through, which in short time will become a leak.

Now how to fix that? well some have tried and been successful for a time, others have tried and had no success, but I will leave that up to them to tell the tales.

 

[Woody]

I will start off with the same disclaimer as Marcarl, I will be very interested in the opinion of others, I'm not very savvy when it come to rusty tanks and what to look for,,, but,,,, I would be sure it is disconnected from the system making sure the petcock is open and wipe it out and then blow it out with compressed air, flush it out with water until it runs clear and watch for any sign of the tank leaking while it is full of water. Then wipe it out and use air to help dry it best you can, connect the line with the old filter in it up fill it with gas and double dose of sea foam and drain that tank through the filter into something you can see the gas in to check it's condition then replace the filter connect everything up and refill the tank after running out that first tank change the filter and monitor the new filter and change as needed. Just my two cents 

[Ashersleap]

I'm going to be doing this soon on the 86 Venture Royale I picked up.  I used to have an old Radian with a rusted tank.  I pulled that tank, pulled the petcock and sealed up all the holes.  Then I filled the tank with BBs and a little clean gas, and just shook the bejesus out of it.  Basically it turned a tank that looked a lot like yours into a clean and shiny tank again.  

It was loud, but it definitely did the trick.

[luvmy40]

A couple handfulls of stainless steel nuts and vinegar works magic too.

Edited July 18, 2022 by luvmy40

[Ashersleap]

Yeah, at the time I was a little afraid of the nuts, due to the amount of corrosion I had in that Radian. The tank was seeming a little thin in spots.  Good tip on the vinegar though....I might try that this go around.

[Pop]

I removed and sealed my tank maybe 10 years ago. I did it because it was clogging my carbs. Has been stored since and I am now bringing her back up. It is quite a job to remove. But if I could do it anyone can. Can't remember where I got instructions but the task was pretty straight forward. This is what I used and had very good results.

https://www.kbs-coatings.com/tank-sealers.html

I have done two other motorcycle tanks with it successfully. If you plan to keep the bike long term it is a good thing to do because the rust will come back.