Got the tank drained...Now what.

[GolfVenture]

Started the process of cleaning out the fuel system.

 

So I disconnected the fuel line right before the fuel filter and put an extension to it. Then placed the extension into a gas can. I put the fuel switch arrow up pointing to reserve.

 

Got all the gas out. The gas all looked extremely clean. Put all the gas into my fuel injection car.

 

Is there anything else one can do to clean out the tank of any debree?

[Black wing]

is it rusty in there or still fairly shiny?

[GolfVenture]

is it rusty in there or still fairly shiny?

 

I'll check tonight or early tomorrow morning. At work right now and my shift is noon to 8:30 pm.

[Peder_y2k]

One can remove the fuel level sending unit from the tank to look down inside. Once the tank is dry, a modified shop vacuum cleaner wand can be worked down in the tank to suck up loose debris. I modded a crevice tool by inserting a 1/2" vinyl tube section sealed with duct tape for the service, and worked the tube around inside the tank.

-Pete, in Tacoma WA USA

'83,88

[Prairiehammer]

One can remove the fuel level sending unit from the tank to look down inside. Once the tank is dry, a modified shop vacuum cleaner wand can be worked down in the tank to suck up loose debris. I modded a crevice tool by inserting a 1/2" vinyl tube section sealed with duct tape for the service, and worked the tube around inside the tank.

-Pete, in Tacoma WA USA

'83,88

 

I know you said once the tank was dry, but the idea of using a shop vac to clean a gasoline tank is a very risky endeavor. The universal motor on most shop vacs use brushes in the motor that arc. And the evacuated fumes are blown right through the motor and past the arcing brushes.

[Peder_y2k]

"DRY" is indeed the key word. Used this technique every time I've had to service the inside of fuel tanks, with no adverse results. Done maybe 10 or so in my lifetime.

Again, "DRY" .... like in zero fuel residue. Oh yes, perfromed task outside in driveway, so if the vacuum blew up, I could step into the neighbors yard and get it back.

-Pete, in Tacoma WA USA

'83,88

[GolfVenture]

"DRY" is indeed the key word. Used this technique every time I've had to service the inside of fuel tanks, with no adverse results. Done maybe 10 or so in my lifetime.

Again, "DRY" .... like in zero fuel residue. Oh yes, perfromed task outside in driveway, so if the vacuum blew up, I could step into the neighbors yard and get it back.

-Pete, in Tacoma WA USA

'83,88

 

 

Pete: Did you vacume up any actual debree?

[Peder_y2k]

Did I find some debris worth the effort? Yes! Don't know what it was inside the tank of my '88 VR, but it did not appear to be rust or rust related, more like 'flakes' and little chips of something that may have been introduced thru the fill neck, maybe even from the fuel itself such as 'varnish'. The dry dusty debris was definately visible and amounted to perhaps a tablespoon in quantity.Tank now spotless with no sign of corrosion even at the welded tank seams.

-Pete, in Tacoma WA USA

'83,88

[GolfVenture]

How about one put some gas in the tank then with a long clear fuel line syphon the gas out and hopfully get the debree out that way.

[dacheedah]

I would think swishing some alcohol around the inside would allow the debris to pool and drain and it will evaporate quickly.

[Peder_y2k]

Better to use paint thinner, or 'white spirits' (Stoddard Solvent) as it/they is significantly less prone to fire, and will evaporate away quickly enough. I use paint thinner for calibrating fuel level in carbs.

"White spirit or Stoddard Solvent" was invented for the dry cleaning industry in the 1920's to minimize skin damage and fire hazard to workers. Straight gasoline with no additives was used previously.

-Pete, in Tacoma WA USA

'83,88

[GolfVenture]

I looked down the tank and at the very top of the neck there is a little bit of rust. Then looking at the seam inside the tank there appears to be some what might look like rust, very little if any.

[Peder_y2k]

The very bottom of the tank should be examined. Remove the fuel level sending unit for access.

-Pete, in Tacoma WA USA

'83,88

[GolfVenture]

The very bottom of the tank should be examined. Remove the fuel level sending unit for access.

-Pete, in Tacoma WA USA

'83,88

 

Can you give me an idea where this sending unit is.

 

How to get to it.

 

What needs to be removed to get to it.

 

Do I need a new gasket for reinstall?

[Peder_y2k]

The sending unit is located at the top of the lower section of the fuel tank. Removing the seat is required. The unit is secured with a medium heavy sheet metal retaing ring that is twisted out and back in, and you will see that. Light hammer taps is all the energy that is required to move the ring to disengage. A light coat of WD40 helps lubricate the process as there will be friction on the seal. A new seal is not necessary in most cases unless the gasket is dray, cracked, or damaged somehow. The two XVZ's I own did not require a new gasket as they were both undamaged and still pliable after 25+ years. If I determined the gasket to be marginal, I would use the black RTV together with the old seal in the final assembly. The black RTV is gasoline and oil-proof, and says so on the label, where all the other RTV products react to gasoline causing swelling and separation of the RTV itself, and this stuff can fall down inside the tank and create havoc. The black RTV is the most expensive on the store shelf, but very cost effective considering.

-Pete, in Tacoma WA USA

'83,88

[Snaggletooth]

Can you give me an idea where this sending unit is.

 

How to get to it.

 

What needs to be removed to get to it.

 

Do I need a new gasket for reinstall?

 

I'm sorry, I'm a bit confused by Peders reply.

 

The sending unit is under the seat mounted on the top of the lower body of the tank. Two wires are plugged into it. You'll be looking right at it. It is mounted on a sheet metal plate with 4 screws. Remove the screws, unplug the two wires and lift the assembly off. Good sized hole there where you can see very well into the bottom of the tank. Visually inspect the pickup screens while your're in there. That was where all my problems started when I had my rust problem. Mine were broken off.

 

There is a gasket on that mounting plate. I've had mine off three of four times and it reseals fine. Remember that sending unit mounts BELOW the fuel level when the tank is filled so make sure it's tightened down and not leaking when you done.

 

The first time after lining my tank and filling it I kept smelling gas. Found that gasket seal was just weeping a bit. Snugged down those 4 screws a bit and that took care of it.

 

Be careful, it's a gas tank and you will be dealing with fumes empty or not.

[Peder_y2k]

OOPS.... big mistake I made. I must have been thinking of a different (Honda) fuel tank system at that moment I responded.

The sending unit is indeed retained by 4 small bolts, 10mm head, and easily removed. Just be careful pulling up the assembly so as not to strain the gasket if it sticks, if it does, use a blunt tool to help it separate to keep the gasket together. On reassembly, the bolts should just be snug with a 5in box end wrench. Back up the gasket seal with the black RTV if you must.

Sorry for the confusion, next time I'll finish my morning coffee before trying to think!!

-Pete, in Tacoma WA USA

'83,88

Edited April 11, 2013 by Peder_y2k

[GolfVenture]

I got the sending unit off. The tank looks really clean. A tiny tiny bit of debree.

Whats the recommended way of removing the rust at the very top of the tank neck?

Afterwards I'll get a couple of gallons of paint thinner and pore it down the tank.

Swich it around some then use some fuel line to syphon out the debree and the paint thinner. Then let it dry.

While I’m at this point, about a year ago several members recommended putting a hole near the top of the neck so one can get more fuel in. On a 1^st Gen where does one do that?

[dacheedah]

Get a couple gallons of metal rescue, fill your tank to the top and let it sit over 24hrs, then empty out and clean with degreaser ( usually one is recommended by your coating kit or included) and at this point remove petcock and fuel senders and put tape on the outside covering those holes, then coat the tank and you are moving the tank around slowly allowing the coating to cover the entire surface. Let it dry slowly and cure, reassemble and put it back on and you should get many more years out of your tank.

Edited April 10, 2013 by dacheedah

[Peder_y2k]

For the rust removal at the top of the fill neck, I'd try using a small hand held wire brush that can fit down there. These little brushes are similar to toothbrushes, often sold in 3-packs with one brass bristle, one natural bristle, and one steel bristle. Stainless steel bristle can also be found. Any brushings will simply fall into the tank where they can be vacuumed up through the sender access hole.

 

That drilled hole you mentioned would be located in the filler neck sleeve that projects down into the tank. The hole relieves air pressure that builds up. IMHO, the function of the sleeve is to support the gas nozzle tube. Or, maybe to minimize overfilling.....don't know. When drilling that hole, the drill chips will go down inside, and can be vaccuumed out.

-Pete, in Tacoma WA USA

'83,88

[Peder_y2k]

If the small amount of rust is really minimal, sealing the tank is not necessary if one continues a regimen of Seafoam, and keeping the tank full of fuel. Airspace inside the tank is responsible for the condensation process that develops and produces the water that causes the rust. Prevent condensation, and with routine removal of the water via the Seafoam, the tank will not continue to rust any further.

Coating the tank is a major PIA.

-Pete, in Tacoma WA USA

'83,88

[Prairiehammer]

I may be beating a dead horse, but all this talk of vacuuming and drilling around the gas tank is scaring me. I certainly don't want to learn that this exercise in cleaning a tank has resulted in singed eyebrows or much worse.

A friend of mine was installing a gas tank in a car last fall when it exploded. The force of the blast broke his neck and he has spent the last several months recovering. The tank he was installing had been sitting empty and open to the atmosphere (through the removed fuel pump port) for several days and yet...

As I have said before, the use of any electrical tool, be it shop vac or electric drill in the vicinity of the open gasoline tank is an accident waiting to happen.

Brian, the creation of a hole in the filler neck is a Second Generation tip to allow more fuel. I am not certain that it is an issue with the First Generation. Even if you decide it is important, do not use an electric drill motor to create this vent hole.

If you feel you must clean the rust with a wire brush, use a brass (non sparking) wire brush.

Be safe. I am continually amazed at the lackadaisical attitude people exhibit when it comes to gasoline. Gasoline and it's fumes are dangerous!

[GolfVenture]

I may be beating a dead horse, but all this talk of vacuuming and drilling around the gas tank is scaring me. I certainly don't want to learn that this exercise in cleaning a tank has resulted in singed eyebrows or much worse.

A friend of mine was installing a gas tank in a car last fall when it exploded. The force of the blast broke his neck and he has spent the last several months recovering. The tank he was installing had been sitting empty and open to the atmosphere (through the removed fuel pump port) for several days and yet...

As I have said before, the use of any electrical tool, be it shop vac or electric drill in the vicinity of the open gasoline tank is an accident waiting to happen.

Brian, the creation of a hole in the filler neck is a Second Generation tip to allow more fuel. I am not certain that it is an issue with the First Generation. Even if you decide it is important, do not use an electric drill motor to create this vent hole.

If you feel you must clean the rust with a wire brush, use a brass (non sparking) wire brush.

Be safe. I am continually amazed at the lackadaisical attitude people exhibit when it comes to gasoline. Gasoline and it's fumes are dangerous!

 

I'll get a brass wire brush.

 

Has anyone, did the hole in the neck on a 1st gen. What if I use a hand cranking drill?

 

i do want to be safe.

[Peder_y2k]

You are darn right that gasoline is dangerous. Afterall, one gallon will propel a 2000lb projectile a distance of 30 miles!! Think VW beetle. If the conditions are treated with respect, then a fire/explosion hazard is almost nil. When I repair a drained and rinsed tank with solder or welding, I fill the tank with water and let it stand with top open overnight. This forces the gasoline vapors out, as gasoline is lighter than water. Then purge the water. I refill with water before intoducing spark or flame to the work area.

 

I once had a fire start when soldering a copper pipe that had anti-freeze in it. Whooda thought anti-freeze is flammable?

 

As with all combustibles, due caution is advised, and forethought is required.

-Pete, in Tacoma WA USA

'83,88 On the '88VR, now adjusting float levels using paint thinner (same specific gravity and density as gasoline), but much less prone to fire, and it dries away reasonably fast)

[Snaggletooth]

Brian, I'm going to say this. If the tank looks clean and very little debris with no major rust flaking in sight you're probably in better shape than you think. If you you want to make SURE you NEVER have a future problem with the tank the only way to assure that is to remove the tank and treat it with a sealing liner.

 

I agree, it is a bit of work but for the long run, it's the only way not to worry about it.

 

I used this product when I did my '84 tank, and several other types of tanks since. I feel, and some will feel differently, that it is the strongest and most reliable material to use.

 

http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html

 

Why? Because unlike many other sealers you do NOT have to remove every bit of rust in the tank for it to bond. It will actually form a stronger bond on a rusted surface.

 

Just pull the tank, pressure wash inside at a car wash, a lil shake, rattle and roll with a handfull of nuts and bolts, power wash again, rinse with some alcohol and let it dry out.

 

Mix the epoxy, seal off the tank openings and pour it in. Rotate tank repeatedly until all interior surfaces are covered. Let it cure for a couple days.

 

You end up with a glass tank that feels like the inside of a Thermos bottle. I've opened mine up every spring to eyeball the tank since I did this. No sign of any change in condition. It's slick as a whistle in there. No sign of any failure of the sealer.

 

It's pretty fool proof if instructions are followed. Mix ratio and temps are important.

 

So there ya go. Two choices. Accept the condition of the tank as is, or go for the seal job.

 

In this case you are probably fine from what you have said. I have never met you but from our exchanges and what I've read about your bikes, I know you want to have it right long term plan. So that leaves only the two opitions.

 

There, my sealing rant is done.

 

Don't forget to change your fuel filter either way.

 

Mike