Now I'm a little nervous.

The following photos show two BVM fuel stoppers from tank kit #T619. I bought two kits. One I used on my 32 oz main tank, and one I used on the 24 oz collector tank.

I've only run 2.5 gallons thru this new jet.
While removing my engine from the jet today, the stopper on the 32 oz seems fine, but the 24 oz tank stopper came apart in my hand. I'm using clear K-1 and 2380 synthetic.

The only thing I can figure is the smaller 24 oz tank with the bad stopper is not always emptied during a typical flight, or engine run. The UAT is the next tank in line from it. Maybe that stopper soaks in fuel more. But should it have disintegrated? The UAT and in-line filter is clean , but there were large and small pieces of the stopper in the tank floating around. These stoppers have only been in use for three weeks. How often should I replace them? I'm wondering if my other jet buddies should do an inspection on their jets.

Chris

Looking at the bad stopper closer, it appears to have compressed more with the set screw. Maybe that cracked the stopper and allowed fuel to soak in. I don't know. If this is the case, I would think Kevlar tanks could cut into a stopper even more if there are rough edges at the opening. My Dubro tanks seem to have smooth openings.

I decided to do some testing for myself. I took a new DuBro black gas stopper fresh from the package, and soaked it in my K-1/2380 mixture from my fuel can. After 3 hours it looks like that in the photo. Unfortunatly, within the first 30 mins of soaking it was already deforming. I need to go to the Hobby shop and buy the brown stoppers, and others intended for gas, diesel, and Kero for soak testing. I'll post my findings. I've done a search on RCU regarding this subject with little results.

I'm not sure what brand to use in my jet now. Am I doing something wrong here?

Thanks,
Chris

Are you using acid for fuel


I use the brown ones without any problems.

I thought BLACK was for glow fuel only or smoke only. I have always used BROWN for kero or gasoline. Russ

Yep you need the brown one my friend from dubro

The below is right from BVM Jets website.......

NOTE - Aluminum Tank Cap Fittings purchased during 2003 have rubber stoppers that can deteriorate due to additives in the gasoline from some states such as California and Indiana.

The black rubber stoppers purchased from BVM post January '04 are ok. Of course, BVM will replace any problem stoppers at no charge.

NOTE - There is no problem with any black stoppers using Jet-A or Kerosene fuels.
Are you sure you're getting kerosene?

Dave

Unfortunatly, the BVM kits are supplied with a choice of only black or white stoppers. The black ones are supposed to be good for Kero. The web site also confirms there should be no problem with the black ones with Kero. I read the instructions, now I'm confused, and my jet is grounded.

Brown? I believe only Dubro has brown ones redily available. I will certainly test them. I will also be looking closely at the Kero. Could I have bad fuel? We'll see.

At work this week, I'm going to use Jet-A (JP-8) from a fuel sample we have to take prior to T/O, and soak some more stoppers.

I had the same problem with a BVM black stopper. I only use the brown stoppers now.

Since I now have an engine problem, I need to keep an open mind. Could the fuel have destroyed the stopper which then contaminated the engine? The UAT and on-board engine fuel line filter looks good.
The engine, jet, tanks etc, etc are all new. Thanks to Scott Harris and his expert flying, the dead stick landing was on the numbers. No damage. 2-foot flame in flight forced us to kill the engine.

My feeling at this point is the engine problem may be totally unrelated to the stopper coming apart. The bad stopper was a lucky find I made while pulling the engine.


In the mean time, I'm going to also check at work for some kind of fuel test paper, or possibly an aqua-glo test (sp). Probably won't tell me much, but I got to decide what to do with 7 Gals of mixed fuel. The Kero was purchased from a local station. The pump was clearly marked Clear K-1 undyed. It looks like Kero smells like Kero, and tastes like kero... Nowhere can I find the stuff in the sealed 5-gal cans.

Does anyone know how to test for Moonshine other than the old fashioned way?

Thanks,
Chris

Thanks for the input.
What has me scratching my head is why one of my BVM stoppers installed at the same time, shows no signs of degredation.
Was the other from a bad lot? Rubber compound broke down? What?

Gary,
Other than Dubro, are there other sources of brown stoppers for my test?

Thanks,
Chris

The question begs to be asked...
Have you contacted BVM Jets about it????

Dave Rigotti

Sullivan makes a gas stopper which is black. I've wondered if that is what BVM sells.

The Dubro is the only brown one I know of:

http://www2.towerhobbies.com/cgi-bin...?&I=LXD755&P=0

BTW - I installed 4 BVM black stoppers at the same time in the same airframe. Only one of them went bad.

Sullivan makes stoppers BLACK for gas, white for glow and Dubro is black for glow and BROWN for gas.

So not all black stoppers are ok for gas/kero.

Is it possible that the black (gas) stoppers got mixed up with black (glow) stoppers?

I have a small bin full of both types of black stoppers and I marked them accordingly

Jake

Dubro screwed us all with their new stoppers---For YEARS (actually decades) the Dubro stopper for gas was black and the glow was a whitish grey. Now the glow is black and the gas is a brownish color. Thanks Dubro for screwing up the works without telling anyone.[:@] I just pulled a stopper out of a gas plane for this reason....

Kevin

BVM has this posted on their web site under the fuel fittings.

NOTE - Aluminum Tank Cap Fittings purchased during 2003 have rubber stoppers that can deteriorate due to additives in the gasoline from some states such as California and Indiana.

The black rubber stoppers purchased from BVM post January '04 are ok. Of course, BVM will replace any problem stoppers at no charge.

NOTE - There is no problem with any black stoppers using Jet-A or Kerosene fuels.

Maybe there is some additive in the fuel you are using??

Just go with the DUBRO brown, local hobby shop will have them and there will be no more issues. As for your engine, YES the rubber from the stopper has most likely stopped up your fuel rail, these injectors are microscopic small. If the engine now has a running problem, that is where to look. Russ

The point is, these stoppers are sold for use in turbine aircraft, as long as you use the black one. I don't imagine I'm the only one that bought this stopper for a jet. Maybe I was. There is however a chance I got the only bad one in the lot. To further clarify, the first thing I did upon teardown was make sure the stopper came from a BVM kit, and was not a DuBro. The differences are obviuos. Larger holes and only two of them compared to the smaller three holes in the Dubro. I don't own Sullivan tanks, and my Great Planes tanks have small stoppers.

I was going to keep this to myself until I realized my buddies and other RCU readers might appreciate the notice and want to spot check their jets if they are using the BVM or any other Kero/Jet-A compatible supplied black stopper. If their stoppers are good, great. No worries.

For now my jet is grounded waiting on the engine and my own personal testing. I will test the brown ones. You know what they say, fool me once, shame on them, fool me twice, shame on me.
I and some fellows at work, are checking the fuel. So far there is no evidence it is not K-1 or contaminated, but we are still checking. The oil was purchased at the Bowling Green KY airport . For 13 bucks, and the feel and smell, it is clean 2380. All my co-workers agree.

As for the engine, I am refraining from any conclusions until the factory has a chance to look at it and tell me what went wrong. The stopper could have been a coincidence. I will call BVM when I have more info. One of the two stoppers I have is fine so far. So this is not an issue with all black stoppers. My guess is this is an isolated case. Rubber does rot on occasion, and break down with exposure to almost any fuel.

I'm a lucky dude, I still have the jet. (Thanks Scott)