1994 K75S fuel tank leak repair and replacement options

[jeks]

hi,

i have a 1994 k75s i'm trying to keep on the road, one of the problems i have is the leaky fuel tank problem at the bottom corners, started as puckered paint and has now progressed to a slow seeping leak.

I tried a couple of things to fix it, first i tried the POR tank repair kit, but that failed miserably failed to bond to the tank and peeled off. Next i tried using jbweld the putty kind where you knead it together.... i suspect that i did an incomplete job as i focused mainly on the 'spots' i could see vs trying to seal the whole seam.

anyway, my questions are.. is a tank repair using jbweld or similar possible if I try to seal it one last time, or is my tank done in?

if i want/need to replace the fuel tank... does a replacement tank need to come from only a K75S or will other K bike tanks swap in?

thanks for any advice!

-jackson

 

[8ninety8]

Google RedKote, read up on it. No mixing, no magic ingredients, no cross yer fingers voo doo. Call'm up. FWIW.

 

[ted]

Try local radiator shops to see if they have someone qualified to do an aluminum braze repair. Not as cheap or easy as some options, but it is as permanent as you can get.

 

[pglaves]

If done properly an exterior patch can work and last for many years. I've had it last 8 or 10 before it started leaking again.

First off, you need to get all the dissolving paint and corrosion off the leak area so you can get a good bond on clean aluminum or undamaged paint. They I coated the area along the leak with Seal All because it is a good sealant and is relatively impervious to fuel - moreso tha JB Weld. But then for some additional body I used a layer of JB Weld. After allowing it to cure for a week or two I touched up with some paint.

Other products work too but the key is wire brushing and sanding down to bare aluminum. You can't seal a leak on top of gunky dissolving paint.

 

[jeks]

hi tanks all for the tips and advice.. i feel very encouraged about keeping my bike on the road.

when i tried to fix the tank before i was only doing patches on the inside of the tank because i was trying to save otherwise gorgeous paint on the outside, but since then my bike got stolen (recovered) and the paint is ruined anyway so just trying to keep her on the road.

however due to insurance claim i could splurge on a new tank...

can anyone tell by sight if this tank will fit a 94 K75S?



thanks for all the awesome advice i just re-subscribed the the MOA even tho i have a (almost working)BMW ;-) you all rock

 

[98lee]

Jackson,

Yes, that tank will fit a K75S.

An S requires a tank from a K75 S,C,T, or standard. A K75RT tank will not work nor will any K100 or K1100 tank.

The difference is the bottom side edge about half way back. It is under cut on an S to clear the fairing.




The K75RT, K100, and K1100 is not under cut.



Being your bike is a '94, it probably has the wider front frame mount. If the replacement tank is the older narrow mount, you can remove the front mount extender tubes and just mount the front rubber mounts straight to the frame like on the earlier bikes.




To remove the tabs (for the low seat tank surround) that are on the side of the tank you pictured, use some fishing line leader and "saw" them off. Then use Goo Gone or other citrus based adhesive remover on what's left.

 

[jeks]

lee, thank you as always for great info!

the tank is from a 94 so i think i got lucky.

wonder if you know, on the tank photo i posted... what is the black tab thing near the back on the side?

TIA

 

[98lee]

Jackson,

As I mentioned in my previous post, those are clips for the rubber tank surround used on low seat models. Use some fishing leader or dental floss to "saw" through the double sticky back mounting tape and then use some adhesive remover to clean the rest of the adhesive off the tank.

 

[jeks]

lee, of course you answered the question before i even asked it, sorry for missing that. and thank you for the rock-solid advice as always.