Funny thing, My rh cap started leaking the last fuel flights, blue streak down the wing. My caps were installed in 2008 - No issues until now. There was definite contact evidence on the chain retainer punch tab from the cap. I got rid of the chain and flattened the retainer, also installed new U-shaped cap seals. No more issues. Monarch recommends changing the seals every 5 years. My opinion, once the U-shaped o-ring gets older and looses its full size, the cap starts contacting the retainer preventing full o-ring compression. I bet the new seals would have been enough, but the chains were a pain anyway. Once the retainer is flattened, I bet you could use a standard o-ring as long as the umbrella didn't bottom out first.

I think there should be an AD to get rid of the chain and flatten the punch retainer. Change the seals every 5 years. Simple as that, then you would have a great cap.

I wouldn't sell them. I think overall they are a quality product.

Sent from my iPhone using Tapatalk

Well apparently it's mine turn now. I've got four of these garbage can lids on my new 185. And fuel streaking down the wing. What rubbish. My last 185 had the raised Cessna plates and caps. Never had a leak, never had to replace o-rings, and who knows how long they worked just fine before I bought the plane and added 600 hours to her. And I don't like the idea of having four permanent spoilers on the wings interrupting the lift. I ordered four of the gold plated, diamond encrusted o-rings, $26 each- give me a break. I will cut the chains and smash the keeper. But I want to replace this junk with the raised Cessna plates and caps. Anyone have a source on these?

Not sure if they have them but you can give them a call.
Sutton Aircraft Salvage 907-754-6969
Copper River Airmotive 907-822-4004
Wentworth Aircraft MN 612-722-0065
DENNY

Thanks Denny!

Too bad the second manufacturer didn't keep making them exactly like the originals. My 1990 caps still don't leak and I have never done anything to the "U" shaped rubber gasket. No lube, no nothing. I do wonder how many clicks they will have when tightening though.

I just checked on some new Monarchs for a 182E. $1058 plus shipping...

D.

My turn.

No big leaks for 1 year and then I started seeing bigger leaks. I’ve read all of the horror stories and potential fixes I called and spoke to them after last big leak and wasn’t impressed, unfortunately. I bought 4 tanks and 4 caps from them. They said my vent location must have changed. He said that’s the only cause. My vent location hasn’t changed as I scribed it with hairline marks to check on pre-flight. It’s never moved from either axis. I removed the chains, bent the tab, did new gaskets, but no luck. I take special care to screw them down and I hear the rubber gasket squeak as it secures and clicks. Still no luck. We installed and adjusted the vent per Monarchs guidelines and not Cessnas.

I’ve seen Marty say his old original monarch caps don’t leak, so I preemptively picked some up cheap off of eBay. Low and behold....I haven’t had a single drop leak out since changing to the old gold colored caps, even with the old o-ring they came with. I even filled it up enough to get fuel on top of the flapper. I’ll keep an eye on it and continue to closely monitor, but so far so good. Glad I had the EI fuel sending units telling me what was going on...it’s actually why I installed them in the first place.

On a 2.0 hour flight I lost 30 gallons (that’s not a typo).

Next troubleshooting step will be to install the Cessna raised lids and caps sitting on the parts shelf.

On a slightly related note, my AUX tank caps also leaked (big time) until I started running double gaskets. I’m currently waiting on them to send me replacement AUX caps because pieces of rubber have been falling out of them. They too are 1 year old. They’re sending replacement AUX caps at no cost, which is nice, but its all very frustrating. I’m really surprised the FAA has never chased this one...

Thanks for the update on using the old caps like have had for 30 years. I can't figure out why they changed the way they made them when they took over from Bill Barton that was the inventor. I actually didn't think you were supposed to change an STC'd item.

I installed Atlee Dodge's cap adapters in my 205, and have been very happy with them. They fit into the existing cap mounting hole with a greased O-ring rather than replace the plate, and use Cessna fuel caps. It took about 15 minutes to install everything and do the paperwork. No fuel leaks, and trace water (two teaspoons) combined across all tanks after two days of downpour. About $600 plus caps.

jcadwell wrote:I installed Atlee Dodge's cap adapters in my 205, and have been very happy with them. They fit into the existing cap mounting hole with a greased O-ring rather than replace the plate, and use Cessna fuel caps. It took about 15 minutes to install everything and do the paperwork. No fuel leaks, and trace water (two teaspoons) combined across all tanks after two days of downpour. About $600 plus caps.

Thanks for that picture. I've been thinking about putting these in my 206 but wasn't sure how they worked. I put new Gallager Orings on my stock caps so I'll see how they keep the water out. Next step will be these adapters.

I’ve heard only great things about the Atlee adaptors.

I never had water once in my tanks with the old flap jack recessed caps and it was parked outside plenty in the rain. With the monarch caps, I see water in my sump cup pretty regularly.

jcadwell wrote: I installed Atlee Dodge's cap adapters in my 205, and have been very happy with them. ....

Those look nice, very clean installation.
Like slow18, I've never had water in the fuel with the flap-jack covered stock caps on my 53 model..
When I bought it, it came with a set of uninstalled Monarch caps,
but instead of fixing a non-existent problem I decided to sell them off.
After reading about the grief that some folks have had with their Monarch caps,
I'm really glad I did.

Someone pointed out that Cessna caps do fit the monarch aux tanks. I tried it and they do fit really well.

My turn I guess,

I have been battling leaking Monarch’s for a few years on my personal 185. The chain cutout was a problem…but no dice. New seals, HOURS adjusting the vents to within what Monarch says, new vents. My (rather expensive) airplane now has sharpie marks all over the vents and struts to verify location prior to flight, as per Monarch. The bastards still leak when topped off. These caps have cost me a lot of time, money in parts, money in fuel lost over the wing, and my trust in my airplane. I never know how much fuel is actually on board.

To top it off every conversation I have had with Monarch has been less than impressive. They immediately take a very condescending tone and tell me that I’m doing something wrong (which I am always open to, I wasn’t the top of my class….). He said he “doesn’t have record of new seals ever being purchased for that airplane, that’s your problem”…..when HE PERSONALLY sold me a set of their unobtanium seals just a few weeks prior. When I pointed that out his answer changed quickly to “oh there’s that record, yup your vents are in the wrong position”.

They. Still. Leak.

Finally found old plates and these turds are going into the landfill where they can’t hurt anyone.

An 8010-4 form is being filled out…you’re mileage may vary, however I cannot in good conscience recommend these or install them on an airplane.

I guess it's my turn. I have had my 182E for six years. The Monarch caps started leaking 4 or 5 months ago. I ordered new seals and I still have the same problem. Hartwig's recommendation is to replace the fuel caps at $600+ a pop. They also say they've never had this problem if the caps are tightened properly. I followed their directions to a T and they still come loose. Not every time, and sometimes just enough that I don't feel any resistance when removing them, making me think they were about to come loose. One time I found one half way unscrewed. I called Atlee Dodge and they no longer make the adapter as on the 205. I don't really want to go back to the Cessna setup. I was wondering if there was a source for parts like Atlee Dodge used to make that I could put together and get a field approval. In the mean time, I've taken to taping down the front edge of the caps to the wing with HVAC metal tape. It is 100% effective...so far, but a pain every time I fuel up. Any thoughts would be appreciated.

I have had monarch caps on my 77 180 long range 4 caps since 2001 .they started leaking 3to 4 years latter .complained same as every body .nothing worked until I resealed the adapter plate and retorgued a few times after . Never leaked again never modified chain hook.vent never issue. My plane after landing go to a cap undo and push on flapper air pressure blows up at me.the venting system pressure tanks up a bit. Another note fuel cap from my 1997 gm half ton fits right on and o ring is the same.cap has same venting and if u wanted to u could put locking cap on as I did if some where u might be worried. Monarch probably used that cap and put there lid on . I have put 3000 hrs on those caps would not get rid of theme .

The easiest fix is to find some of the old original gold monarch caps. Occasionally, they show up on eBay or you can see if skywagon city has them. They solved my Monarch saga. My experience with customer support was the same as you describe. Very condescending tone. I felt like he didn’t care that I paid him for their product. I bought 4 tanks and 4 pairs of caps from them and they weren’t nice to me when I had an issue. Strange….

I agree with slow18. I bought and installed the original style in about 1990 from the inventor and they work flawlessly. Whoever decided to change things made a big mistake!!!!!

Can that type of Atlee Dodge fuel cap adapters still be bought some place?