Early RV6 Fuel Cap Identification

[wfixnfly]

Trying to find out more about our fuel caps installed on our 1991 RV6. We are not the original builders, are trying to determine who (vendor) made our caps. There are no teflon washers on either of our cap's castings. The 1st Attachment shows one of our caps partially disassembled with the o-ring removed. Anyone familiar with our caps - who the vendor is, if there are supposed to be teflon washers on the cap castings?

The latest cap information from Usher/Van's shows that both castings have tapered seats with teflon washers, see 2nd Attachment. Our top casting has a tapered seat while the bottom casting has a flat seat. I've contacted both Van's and Usher PM - neither had information that shed light on what we have.

Thanks in advance for the help!

 

[rvbuilder2002]

Trying to find out more about our fuel caps installed on our 1991 RV6. We are not the original builders, are trying to determine who (vendor) made our caps. There are no teflon washers on either of our cap's castings. The 1st Attachment shows one of our caps partially disassembled with the o-ring removed. Anyone familiar with our caps - who the vendor is, if there are supposed to be teflon washers on the cap castings?

The latest cap information from Usher/Van's shows that both castings have tapered seats with teflon washers, see 2nd Attachment. Our top casting has a tapered seat while the bottom casting has a flat seat. I've contacted both Van's and Usher PM - neither had information that shed light on what we have.

Thanks in advance for the help!

You probably still have the original cap that shipped with the kit, which is the earliest version considering the age of your airplane.
I suggest you just buy two new caps. The flange portion inside the tank was the same for all versions so the new caps will fit your tanks fine.

 

[gasman]

Your cap looks good. No missing parts. Teflon was not used on these, and not needed. The disc pushes the "O" up the taper and locks the cap.
Remove and install the nut and base with the tab closed. This will reduce the chance of breaking the pin. The base is threaded and is used to adjust the cap for proper grip in the tank. The nut is just there to lock the adjustment in place. The "O" rings can be purchased at an ACE hardware store or a NAPA autoparts store. Lube the "O" rings with

Krytox by Chemours GPL 205 Grease, Pure PFPE/PTFE, 0.5 oz .​

Purchase from Amazon.... about $25 But it works and a tube will last a lifetime.

Adjust the cap so the cap (in open position) will just drop into the neck of the tank. When complete, install the jamb nut.
A properly adjusted cap that is lubed with Krytox will open with a finger, and you will just barley be able to rotate the cap in locked position with your fingers pressed on the cap.

 

[Tracer 10]

Trying to find out more about our fuel caps installed on our 1991 RV6. We are not the original builders, are trying to determine who (vendor) made our caps. There are no teflon washers on either of our cap's castings. The 1st Attachment shows one of our caps partially disassembled with the o-ring removed. Anyone familiar with our caps - who the vendor is, if there are supposed to be teflon washers on the cap castings?

The latest cap information from Usher/Van's shows that both castings have tapered seats with teflon washers, see 2nd Attachment. Our top casting has a tapered seat while the bottom casting has a flat seat. I've contacted both Van's and Usher PM - neither had information that shed light on what we have.

Thanks in advance for the help!

 

[Tracer 10]

Trying to find out more about our fuel caps installed on our 1991 RV6. We are not the original builders, are trying to determine who (vendor) made our caps. There are no teflon washers on either of our cap's castings. The 1st Attachment shows one of our caps partially disassembled with the o-ring removed. Anyone familiar with our caps - who the vendor is, if there are supposed to be teflon washers on the cap castings?

The latest cap information from Usher/Van's shows that both castings have tapered seats with teflon washers, see 2nd Attachment. Our top casting has a tapered seat while the bottom casting has a flat seat. I've contacted both Van's and Usher PM - neither had information that shed light on what we have.

Thanks in advance for the help!

Older Usher Fuel Cap O-Rings: Large. AN 6227B-29 or MS 28775-326 Small. 2-102 Aircraft Spruce. Lube very sparingly with Krytox grease.

 

[RV6_flyer]

Those are the early Usher fuel caps like the ones that came with my RV-6 kit. They were early design with flaws. The correct thing to do is replace them with new Usher fuel caps that are in current production. Like Scott said, buy new ones as they will work with the flange installed in the tanks.

 

[wfixnfly]

You probably still have the original cap that shipped with the kit, which is the earliest version considering the age of your airplane.
I suggest you just buy two new caps. The flange portion inside the tank was the same for all versions so the new caps will fit your tanks fine.

Thanks!

Those are the early Usher fuel caps like the ones that came with my RV-6 kit. They were early design with flaws. The correct thing to do is replace them with new Usher fuel caps that are in current production. Like Scott said, buy new ones as they will work with the flange installed in the tanks.

Those are the early Usher fuel caps like the ones that came with my RV-6 kit. They were early design with flaws. The correct thing to do is replace them with new Usher fuel caps that are in current production. Like Scott said, buy new ones as they will work with the flange installed in the tanks.

Thanks!

 

[wfixnfly]

Your cap looks good. No missing parts. Teflon was not used on these, and not needed. The disc pushes the "O" up the taper and locks the cap.
Remove and install the nut and base with the tab closed. This will reduce the chance of breaking the pin. The base is threaded and is used to adjust the cap for proper grip in the tank. The nut is just there to lock the adjustment in place. The "O" rings can be purchased at an ACE hardware store or a NAPA autoparts store. Lube the "O" rings with

Krytox by Chemours GPL 205 Grease, Pure PFPE/PTFE, 0.5 oz .​

Purchase from Amazon.... about $25 But it works and a tube will last a lifetime.

Adjust the cap so the cap (in open position) will just drop into the neck of the tank. When complete, install the jamb nut.
A properly adjusted cap that is lubed with Krytox will open with a finger, and you will just barley be able to rotate the cap in locked position with your fingers pressed on the cap.

Thanks!

 

[Snowflake]

Huh. Today I learned there should be a small O-ring under the washer in the cap. I'll have to take a look the next time i'm at the hangar. I don't recall ever seeing that, and my caps have never leaked through the cap...

 

[wfixnfly]

Those are the early Usher fuel caps like the ones that came with my RV-6 kit. They were early design with flaws. The correct thing to do is replace them with new Usher fuel caps that are in current production. Like Scott said, buy new ones as they will work with the flange installed in the tanks.

Your cap looks good. No missing parts. Teflon was not used on these, and not needed. The disc pushes the "O" up the taper and locks the cap.
Remove and install the nut and base with the tab closed. This will reduce the chance of breaking the pin. The base is threaded and is used to adjust the cap for proper grip in the tank. The nut is just there to lock the adjustment in place. The "O" rings can be purchased at an ACE hardware store or a NAPA autoparts store. Lube the "O" rings with

Krytox by Chemours GPL 205 Grease, Pure PFPE/PTFE, 0.5 oz .​

Purchase from Amazon.... about $25 But it works and a tube will last a lifetime.

Adjust the cap so the cap (in open position) will just drop into the neck of the tank. When complete, install the jamb nut.
A properly adjusted cap that is lubed with Krytox will open with a finger, and you will just barley be able to rotate the cap in locked position with your fingers pressed on the cap.

You probably still have the original cap that shipped with the kit, which is the earliest version considering the age of your airplane.
I suggest you just buy two new caps. The flange portion inside the tank was the same for all versions so the new caps will fit your tanks fine.

You probably still have the original cap that shipped with the kit, which is the earliest version considering the age of your airplane.
I suggest you just buy two new caps. The flange portion inside the tank was the same for all versions so the new caps will fit your tanks fine.

Thanks!