Screw on gas cap
 

My ’29 has a screw-on gas cap that is really hard to line up and screw on because of those super fine threads. Has anyone figured out a way to line that cap up and screw it on easily? It’s hard to imagine a service station attendant back in the day having to spend as much time getting that cap back on as it took to fill the tank. What am I overlooking that would make putting that thing back on easy?

I live in Oregon where legally we can’t pump our own gas, but I wouldn’t ever want anyone else putting gas into that car. Hell, even when I put gas in it from a plastic gas container, I always put a towel around the opening to proect the paint.

Any helpful suggestions are welcome,

Mike

Re: Screw on gas cap
 

That is the way it is. You can’t change it.

I do the same thing you have mentioned. Towel and add gas from plastic gas can. I also add Marvel Mystery Oil to the gas in can before we pour it into car. Do you have screw in screen at top of gas tank opening? If not, you might want to get one. Enjoy.

Re: Screw on gas cap
 

Have you tried a new or different cap ? Or the threads messed up on the tank?

Re: Screw on gas cap
 

Threads on the cap and tank are in excellent condition. I want to keep them that way. That is why I asked about an easy way to screw on that thing.

Mike

Re: Screw on gas cap
 

That's why Ford changed it in 1930.

In designing machines its fairly common to add a non-threaded 'lead in' section to help with part alignment before the threads engage. Ford didn't do that :confused:

You could machine a 'lead-in' into the cap threads, but I'm not sure how many threads you have available to remove for that purpose. The lead-in would have to be a smooth 'slip fit' over the tank threads to work properly though, and the threads on a standard cap may already be cut to deep to begin with.

Or, you can machine out all the threads from a standard cap and make a new threaded insert with a lead-in. Yeah, that sounds cheap :rolleyes:

Or, you could trade your car for a 30-31.

Or, you can be careful with your current cap :)

Re: Screw on gas cap
 

I thought they changed that law in Oregon?

How many people does it take to pump gas in Oregon?
None, they have to get someone else to do it for them.

How many people does it take to change a light bulb in Oregon?
None, if they can't even pump gas keep them the hell away from electricity.

Just kidding...good thing you don't live in the Peoples Republic of California...
I have a million jokes for them nuts..(Born and bred in Cali, but escaped)

Re: Screw on gas cap
 

Try to turn the cap in the opposite direction (unscrew it) a little before trying to screw the cap on. Sometimes this lets the threads drop into the male threads of the gas tank.
Rusty Nelson

Re: Screw on gas cap
 

Oregon only changed the law in counties with fewer than 40,000 people, which more or less covers places in Oregon that don't have many gas stations (or people) any way. I don't think the law applies to motorcycles or things like that, so you might be able to get them to look the other way on the Model A, or at least have the attendant hand you the nozzle once he or she starts the pump. I moved from Oregon to Washington 18 years ago, but I only live about 10 miles from the Oregon state line. When I visit Oregon, I am always forgetting to not get out and pump the gas.

The threads on my '29 screw-on gas cap are pretty decent and the cap just spins right on and off. It's my similar screw-on radiator cap that gives me trouble.

Re: Screw on gas cap
 

Its not so bad in Cal once you're used to it. I've been in Cal since 1975, one day I hope to get used to it...

Re: Screw on gas cap
 

I can make a lot of jokes about other states but this is not the place for it. I have respect for those on this Forum even thought some don't seem to have the same respect for my State of California. Don't like it move, but don't throw stones.

David Serrano

Re: Screw on gas cap
 

I wuz born in Oklahoma & ESCAPED to Sunny California. I'm a CIO (California Improved OKIE!)
Bill Happy

Re: Screw on gas cap
 

X2.... That's what I wanted to say. Thanks Rusty.
Good luck Mike. :)
Jeff

Re: Screw on gas cap
 

Just tell the attendant, if you can figure where the gas cap is, YOU can fill it.

If you cannot guess where it is, I do not trust you to fill it.

Also if they do demand to fill it, say that any spillage will run forward down under the hood and onto the exhaust pipe, so you better have good insurance, then step way back ( for effect).

I bet the attendant wil let you do it then.

Re: Screw on gas cap
 

I always put a little super-lube on the threads on my '28.
It just seemed to make the alignment and thread starting so much easier.

Re: Screw on gas cap
 

I have always been able to fill my model A in Oregon I think just like motorcycles some things are exempt. By the way I like staying warm and dry when I go for gas in my modern iron.

Re: Screw on gas cap
 

X2
Also, do you have an original cap?
My original 28 cap screws on nicely.

Re: Screw on gas cap
 

Well you know what they say Bill:
If you scratch a Californian, you'll find an Okie underneath

Re: Screw on gas cap
 

Rusty's post # 7 is how I have been doing it for 50 years. It may work for you too. Of course, the cap on my '28 is an original from the Ford Motor Company; that may make a difference, as Tom Wesenberg alludes.

Re: Screw on gas cap
 

I have the same issue with the aftermarket gas cap on my truck. I think it's more of a pride issue for me. Having people stare, ask to take pictures and tell you how "sweet" your ride is while your filling the tank...then watch you fiddle with a stubborn gas cap just deflates the "cool bubble" you were just floating in. Sometimes by the time I get it buttoned up the flattering onlookers have walked away.
I just look up and say, "Thanks I needed that."

Re: Screw on gas cap
 

Tom,
I heard you lowered the IQ of both states when you came here. I know I did.
Dave

Re: Screw on gas cap
 

A Californian planted a row of COTTON, to Oklahoma, to get rid of the OKIES, he FORGOT about the SECOND PICKING!!!:D
To succeed in a WAR, fly over & drop Cotton Seeds & the OKIES will INVADE!!!:eek:
Bill Cottonking

Re: Screw on gas cap
 

Ha...okie jokes, love'm. :)

Re: Screw on gas cap
 

Actually that is possible if a person is smarter than the state they left, but dumber than the state they move to. :)

Re: Screw on gas cap
 

Gas cap and radiator both fit well on my 29. Just always been a habit with any fine thread, turn it backwards until you feel the thread drop, then turn it forward. Works with bolts/nuts, precision jar/can lids etc. Coarse threads or anything machined with starter threads not necessary. Grew up on a farm wrenching something my whole life so I don't think twice about some things. I remember laughing when I'd hear someone say before turning a nut "righty tighty, lefty loosey". Doesn't mean those that haven't done it a long time can't do it as well or better, but learning something very early in life makes it second nature. Watch a young teenager run a phone, us older generation will NEVER develop the second nature skills like they have for electronic smart devices.

Re: Screw on gas cap
 

In our Fillin' Station days, Chief was AWKWARD on the phone & Momma would do the ordering, etc. By then, I had lurned to TALK & haven't ever stopped YET!:eek:
Bill Stories

Re: Screw on gas cap
 

The first time I put gas in my 29 Roadster the top part broke so the threaded part stayed on the tank. I used some channel locks to take the threaded part off.

I bought a reproduction cap and it fit perfectly. I have not had any problems threading it back on as reported above.

I'm not sure if the pictures of the cap will show up below. It looks like the two parts are spot welded in three spots. Has anybody repaired these caps before or know anyone who does it?

David Serrano

Re: Screw on gas cap
 

J.B. WELD TO THE RESCUE!!!:D
Bro Bill W.

Re: Screw on gas cap
 

The original cap inner and outer parts are soldered together. I've taken about a dozen 1928-9 caps apart to repair dents and polish them. Took some mint caps to a plater, and never got them back.

Re: Screw on gas cap
 

Tom,

It makes sense that they were soldered in three spots. It doesn't look like they could be soldered anywhere else because there is no access to the back of the threaded piece.

Do you think there was any other type of adhesive on the back of the threaded part?

David Serrano

Re: Screw on gas cap
 

Use a small tip on the propane torch and heat the inner part, and the solder will flow all over between the two parts. This gives plenty of strength. I posted pictures in the past of the caps and the two parts after I unsoldered them. Of course the radiator cap is slightly different on the inner part, since it has no vents.

Re: Screw on gas cap
 

Some reproduction/replacement caps just don't fit right. Mine, for example. The ID of the cap was too large and would not screw down tight. I would look for an original with plenty of wear. Remember, in China they're still getting used to using gas caps. I cuss that thing every time I have to touch it.

Re: Screw on gas cap
 

I have never had an much of an issue with filling my Model T or other antique cars here in Oregon, the attendant hands me the hose after starting the pump and I fill her up and hang the hose back up. They don't want to be libel for scratching the paint, LOL. (You would have to see the paint ha ha)

Re: Screw on gas cap
 

I am from Jersey,and you can not pump your on gas,I fill gas cans and pour them into the A.I never had a problem with the screw on gas tank cap,I would find an original cap if you have a repop this could be your problem.