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Fuel tank mod

S

Stan Bahrns

Active Member
Has anyone done the new mod? I am ready for the inspector & now this mod shows up. I think I remember there being very little room in the left front corner is the reason I'm asking. COMMENTS?
Thanks, Stan Bahrns
 
Hey Stan - -

Just finished it. Not fun, and messy as usual, but it is just another job to do. I stated in another thread that if you are also installing a tank vent, allow maybe 10 hours to work on the tank itself. Tank removal and re-install not included. Also allow a couple hours to do the other parts of the vent if you are doing it.
 
Just wondering as it is not an issue for me, but do all SBs have to be incorporated to get an ELSA A/W certificate if the noncompliant SBs do not say "comply before next flight"? After all your sign off is saying the aircraft is in a condition safe for flight.
 
Service Bullitins

Don't know but going to find out soon. Was ready for inspection until I got the latest fuel tank bulletin so as soon as I get the tank mod done & some taxi test's
I will be ready for the inspector. I will try to remember & let you know. Stan
 
Done

Glad to say I just finished all the mods. Blocked out the sight glass, installed the vent, installed the new structural mod and installed the Moeller fuel gauge. Total time (Approx.) 10 hours. This work was made much easier by removing the tank top. I did order a new top when I placed the order for all the other parts. In view of all the tasks I wanted to accomplish, it was just the prudent thing to do. The new top was only 20 bucks or so and about $10 for rivets. All in all, not a terrible job, except for the snot!:D
 
I just finished up resealing the tank last night after doing just SB 13-12-19. Finicky, messy, and a pain, but doable.

My front cover plate came off relatively easily by using a very thin putty knife working around the cover's circumference with an occasional squirt of WD-40 to keep the knife edge lubed and to prevent the sticky ProSeal from re-adhering to the knife blade. Then I used a homemade plastic scraper (per Van's suggestion) to scrape off the remaining ProSeal residue off of the cover plate/mounting ring followed by a final cleaning/buffing with a small rotary "flapper" wheel -- worked great.

The removal of the interior ProSeal is more problematic. You must do it by feel using Van's suggested plastic scraper (maybe one or two different widths?) -- you can't see the area and a mirror only helps one monitor the progress. The interior ProSeal removal is the worst part of the whole deal. I first tried to do the removal without drilling out the suggested extra side rivets, but alas, their removal did make things easier and it's no big deal replacing them. I also removed the finger strainer for fear that I would get ProSeal all over the mesh part when goobbering-up the corner and the new bolt heads.

The next challenge is to get the washers and nuts placed on the three bolts. Again, doable but messy and frustrating. Gloves proved pretty much useless since you really need the tactile feeling of fingers to do this job.

FYI, the SB can be done with two of Van's small ProSeal (1 oz?) kits. HOWEVER, those small kits are "fast-setting" and you will really appreciate the slower setting time of the standard variety of ProSeal.

Glad its done! Did it over two @ three hour sessions.
 
Thanks. Exactly as I was dreading, getting the insides prepared is a hard task. I wonder if taking off the top instead might be a better way to do it?
 
Thank all you guys......

....... for sharing your experiences. By the time my condition inspection comes up in April I will have all your good ideas to work with re the tank mods. Right now my inclination is to pull off the top and do EVERYTHING related to the tank all in one shot, since this is clearly the LAST time it will be open (he said hopefully!)
 
I finished my tank mods 2 weeks ago (reinforcement and vent) and I had thought about removing the top after I started removing the old proseal around the fuel outlet area. Major PIA working blind for the most part, although I did finally figure out you can peak in the removed rivet holes and fuel outlet flange to see where the scraper is (sort of). The fit up of the new brackets, drilling holes, counter sinking were no problem. The real fun started with the proseal; first problem was proseal on the smaller doubler on the tank skin side, the Clecos did not pull it tight and I ended up with a gap as the Cherrymax CD3212-4-4 rivets did not pull it tight before the stem sheered off. This was similar to the problem on the Fuselage Skin Mod with the same type Cherrymax rivets. Had to drill out three rivets, clean up the proseal mess and start again. On the larger bracket I installed the screws first after clecoing, which took care of pulling the doubler tight to the tank skin. After installing all the riverts, sealing the interior around the small doubler was fairly easy. The sealing around the large doubler was a real challenge as it is all done blind. I ended up ditching the gloves and using my finger to spread the proseal.

The vent mod was nothing compared to the doublers. The worst problem was reaching the back of the tank for tightening the AN nut and spreading proseal around the nut and threads. That reminded me why I did not want to pull the top to do the bracket mods, sealing those rivets at the back of the tank is as bad or worse than working blind resealing the doubler areas.

Looking back, I think pulling the tank top to do the work would have taken longer and would have only traded working blind in the corners for working blind in resealing a whole lot more tank top rivets. The tank has been under pressure for 10 days and no leaks, so it all worked out at the end.

John Salak
RV-12 #120116
 
Easy or fast are not so much my concerns as doing a good job. Cleaning and slobbering proseal in the blind does not assure me it is done well. Then too you need to be careful of the drain holes in the bottom of the baffles. I think for peace of mind I will pull the top.
 
I believe Scott mentioned it - -

the next day after 'gooooing' the tank back together, if you put balloon pressure on the tank and spray a serious soap and water mix on all parts of the tank, you we know if you have any leaks. Still needs to sit for a while, but you don't have to wait days to be sure you got it sealed. Spray clear water on it after you KNOW there are no bubbles, then let it dry and sit for a few days. A tiny air leak can take a long time to notice the balloon is going down.
 
With either the balloon or the water column, there will be changes - due to temperature. It will drive you nuts chasing the temps, hoping it is temps and not leaks. Bubbles will not lie!
JBPILOT said:
the next day after 'gooooing' the tank back together, if you put balloon pressure on the tank and spray a serious soap and water mix on all parts of the tank, you we know if you have any leaks. Still needs to sit for a while, but you don't have to wait days to be sure you got it sealed. Spray clear water on it after you KNOW there are no bubbles, then let it dry and sit for a few days. A tiny air leak can take a long time to notice the balloon is going down.
Click to expand...
 
Poly tank

Does anyone know why Vans does not have a poly tank like Sonex? It seems so much safer and easier.
 
If you have any plans of replacing the sight glass, removing the top is almost a necessity. That tank is longer than you think and you will have to reach over the baffling to access it. It took about 30 minutes to drill out the rivets and cut the proseal. I was able to use gloves for the whole process and when I was done, had no snot on my hands, clothes, hair, etc. Had to clean a few tools but that was it. If I were doing it again, off with the top!;)
 
Dave12 said:
If you have any plans of replacing the sight glass, removing the top is almost a necessity. That tank is longer than you think and you will have to reach over the baffling to access it. It took about 30 minutes to drill out the rivets and cut the proseal. I was able to use gloves for the whole process and when I was done, had no snot on my hands, clothes, hair, etc. Had to clean a few tools but that was it. If I were doing it again, off with the top!;)
Click to expand...

Hi Dave, My only need for opening up the tank will be to install the two latest corner stiffeners that Van sent out. Now that you have been there, would you still take the top off to do that mod, or would you give working through the sender plate hole a try. Tom
 
I've tried to stay out of this discussion since what is easy for one might be difficult for someone else, but.........

I completed the SB on the tank and frankly, I didn't think it was tough at all. For me, the change is a little more involved than most because my tank is not covered with carpet, it is both painted and polished, both of which had to be redone after the mod. Also, I do not smear Proseal around where it's not needed so fitting the reinforcements were just not that hard to do.

I can understand why it is difficult for some and I'm not implying anything about anyone else. All I'm saying is that if I can build an airplane, fixing the tank just isn't worth losing sleep over. If you are not making the change to the Moeller fuel gauge, removing the top is not necessary IMO, but if you find it easier to do it that way, go for it. I found reaching in through the cover plate to be adequate to complete the SB. Just my $.02 YMMV.
 
Tom, I have only performed this task with the top off and can't comment on the alternative. I am just a bit too ham fisted to work in those blind corners so my thought is to still remove the top. JMO??:confused:
 
Dave, our dexterity is probably very similar. My guess is that you also had to remove the sender plate for access, to ensure the the top was sealed well. If it was just the top, it would be a no-brainer for almost any work inside.

Tom
 
Tom, I did not have to remove the sender plate, absolutely no need to bother it. The float was never in the way.
 
Another step you can skip is removing the rivets from the previous mod and the nut plates if you access it through the top. ;)
 
Type and Thickness

Does anyone know what type and thickness the aluminum van uses for the RV12 Fuel Tank
any help would be appreciated
Thanks
 
answer 2024T3 .032

Thanks
I think the answer 2024-T3 .032
Can someone please confirm
Thanks again
 
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