how long for dry tank to shrink back?

[BK_856er]

No dimensional changes yet (not surprised) but my hole-to-hole measurement with bumpers removed is exactly the same as OrangeDragon reported for his swollen tank = 11 3/4".

I could easily live with the extra width, but the extra length and corresponding interference with the ignition cylinder is the nuisance.

Will do the Marine Clean thing to get more possible surface contamination off.  Maybe that'll speed everything up, and it's reported to be a healthy prep for Caswells anyway, in case I decide to go that route later.

BK

[ducatiz]

Wish i'd thought of doing this over the winter months. I've ordered an ally tank from Beater in japan at massive cost!  Doh!

wait.. what??? they posted a while back they had stopped making tanks!!

[SpikeC]

I recently acquired an ally tank for my bike, it is over 3 pounds lighter than the plastic, butt it does transmit more mechanical noise from the engine! Just be aware of that if it makes any difference to you!

[BK_856er]

Maybe my search skills are rusty, but I can't seem to find reference to the fuel pump flange o-ring standardized number.

Viton is obviously the material of choice.  Round o-ring is typical, but I understand that Ducati retrofit the x-ring type under warranty if pump flanges leaked.

Measurements off my original o-ring are 5mm width x 119mm OD.  This would cross to a AS568A Dash Number 347 o-ring.  Can anyone verify that is correct and an odd metric size isn't required?

BK

[OrangeDragon]

886.4.049.1A    O-ring

This is the number I get from the parts diagram(monster 695) that i downloaded from www.proitalia.com 

[stopintime]

wait.. what??? they posted a while back they had stopped making tanks!!

Wasn't that just that they weren't allowed to ship them?

[BK_856er]

886.4.049.1A    O-ring

This is the number I get from the parts diagram(monster 695) that i downloaded from www.proitalia.com 

Sorry, not ducati p/n, but standardized o-ring number.  O-rings are a bit like fasteners, with standard dimensions corresponding to a "dash" number, but because they're squishy it can be tricky to nail it.  Markup is 10-20x for something like this!  With a dash number you can choose your material and durometer and hit up McMaster or similar.

BK

[ducatiz]

Wasn't that just that they weren't allowed to ship them?

no clue.

[itsamonster]

I ordered it in December from www.samurider.com who handle posting them out.
They said the wait was going to be up to 4 months........ not long now   

[BK_856er]

Three weeks with a strong fan blowing air through the tank 24/7, initially washed with dish detergent, moved indoors next to a large window so it gets warmed up each day.  No measurable change yet in the distance between the bumper attachment holes.  My POR15 Marine Clean shipment leaked and UPS discarded it before delivery - replacement order is on the way again.

Rigged up a seal for the fuel pump opening to help with the next steps.  1/4" plastic cut to 6" diameter with a router jig, tapped in the center for 1/4-18 NPT elbow, oring from bulk pack I keep for my 749s fuel pump.  Looks like it'll work well.  I have extra materials if anyone is interested.

BK

[OrangeDragon]

Nice work on that plastic cover!!  My plexi cover cracked and leaked a little.  luckily the paint didn't get messed up.  there are some good tips on how to coat a tank on DMF, but if you want to avoid some of the mistakes I made here is link to my coating experience:  http://www.ducatimonsterforum.org/index.php?topic=67331.msg1246833#msg1246833   Although I didn't execute the coating all that well, the tank isn't expanding so I consider it a success so far.

[Bill in OKC]

That is a pretty cool seal for the pump.  I am wondering if it might be possible seal the entire tank and pull a vacuum?  Maybe put moisture absorbing silica packs in the tank and pull a couple pounds of vacuum?  It would be interesting to know if it could speed up the drying/shrinking process.

[BK_856er]

I was thinking the same thing.  Put it under a gentle vacuum, load it up with desiccant and keep it warm with a contraption I use to maintain fermentation temps.  Passive shrink-back is sloooooooow.  I'm also hoping the Marine Clean might help remove any thin film of aliphatic contaminates that could inhibit desorption of the water.  Damn plastic tanks.

BK

[ducatiz]

that's a beautiful plug there.  i made one that is two pieces of lucite sandwiched for rigidity but that one looks far more purpose built.

I drilled a hole and used a size 10 stopper in mine.  about 2" in diameter and much easier to pour in and just big enough for my shop hair dryer's nozzle.

I used a stopper for the filler from the outside.  there is a vent that you have to plug as well next to the filler hole, but that's no big deal.

[BK_856er]

The next experiment involved adding a couple pounds of freshly activated desiccant, using the beautiful plug to seal the pump opening, in order to achieve very low internal RH.  Let's see what that does for a while.  My POR15 Marine Clean arrived today, so I'll queue that up next.  On particularly warm sunny days (this is northern California) I put the tank outside in direct sun where it gets hot to the touch for hours.  My goal is to get this b*tch shrunk down by ~May.

BK